Foreplay

The Foreplay 2.0 kit has been retired. We have kept this web page active for reference purposes only, since there are several thousand of these kits in the field. The currently available version of the Foreplay line stage kit is Foreplay III

skill level 1

As soon as we finished designing the original S.E.X. (Single Ended eXperimenter's) amp kit, we knew we needed a line stage preamp to go before it. What else could you call this kit but Foreplay?

Inspired by a design from George Wright, The $179 Foreplay is a line stage with dual mono volume controls, three pairs of inputs and a single pair of outputs. 

Chassis is laser cut .040" brushed aluminum, the wood base is made from beautiful Pacific Northwest alder to which you apply your favorite finish. Tube sockets are high quality ceramic, controls feature attractive black phenolic knobs. In stock form the kit comes with nickel plated RCA jacks, which can be upgraded to the gold plated jacks shown in the picture above, for $25. All wiring is point to point using our special high purity long crystal copper magnet wire, featuring metal film resistors and high quality electrolytic capacitors in the power supply. The circuit uses one 12AU7 tube per channel, or one of the 12AU7 variants, 5814, 5963, 6189, etc. Yes, the tubes are included. We bust our butts to find stashes of old stock tubes, and every one is tested for sufficient transconductance.

One half of the 12AU7 operates as a traditional voltage amplifier, directly coupled to the other half of the 12AU7 which operates as a cathode follower. Output coupling is through a 2 mfd capacitor to assure ample bass response into lower impedance solid state amplifier inputs.

The line stage can swing about 20 volts output, far more than required by just about any amp out there, and the cathode follower insures a very low output impedance, which makes Foreplay able to run amps with finicky input impedances as low as 10K ohms. Gain in stock form is about 19dB. Input impedance is 100K ohms, output impedance is approximately 1300ohms. Response is within +/-0.5dB from 0Hz to 50kHz.S/N is around 80dB (higher with the Anticipation upgrade). Phase in inverted. Here's some more specs, generously offered by bottlehead Craig Lewis. 

Assembly is a one or two evening affair, specifically designed with the first time builder in mind. A very thorough assembly manual is included, containing step by step printed instructions you check off as you go, and a detailed CAD drawing of the chassis underside and all components. And we have experienced builders who have volunteered to link their own valuable experience on our website. All the builder needs to supply is solder.

delivery status

When John Camille came up with the Camille Cascode Constant Current Source, we knew we had to use this sweet little device as an upgrade to the basic Foreplay kit.

C4S is a high impedance current limit circuit for preamp and driver tubes, designed by John Camille. It includes two transistors and two LEDs per tiny PC board (4 boards are provided in the kit) and an extensive 28 page manual written by "Buddha" Camille himself is supplied with the kit to help you understand it's function. This current source may

be used as a plate or collector load for voltage differentials up to 300 volts, so we use it on both the voltage amp stage and the cathode follower output stage, which greatly improves the sonic performance of the cathode follower.

What does all this mean? The 5 megohm effective impedance characteristic of these active loads permits near theoretical gain performance from voltage amplifier stages, and can reduce distortion in vacuum tube audio circuits by several hundred percent. Noise generated in this circuit is up to 40 times less than several commonly used circuits. The result is clarity, bass speed and drive that beats resistive loads, choke loads, and other tube and solid state loading schemes like mu followers/stages and SRPP’s.

With the help of a second comprehensive manual specific to its use in the Foreplay, four of the C4S boards are assembled with the necessary components and installed in the Foreplay, each replacing a resistor in the original design. The result is slightly more gain, tighter bass, and better focus throughout the audio spectrum. With this kit the midrange approaches that of our reference eXception parafeed preamp. All for only $75.

With the Anticipation upgrade, the Foreplay will embarrass an awful lot of lines stages out there at five times the price.

It nicely complements the resolution of our Paraglow  2A3 and Parabee 300B amp kits.

The Sweet Whispers stepped attenuator has been a tremendously popular upgrade to the basic Foreplay kit over the past 5 years. The original design offered major bang for the buck and versatility in attenuation ranges. The body of experience we have acquired from the Bottlehead Community has inspired us to take the Sweet Whispers kit to an even higher level of and versatility sonic quality in the form of Sweetest Whispers, while keeping the original price of just $40.  

The new dual mono attenuators are built on eleven step rotary switches with a positive stop, something that was missing in the original design. The total range of the steps has been increased from the original 30 dB to a total of 39 dB plus a mute setting, in response to requests for a very low level setting for late night listening sessions. 

Perhaps the most innovative feature of this new attenuator is the ability to use it as a 15K ohm series attenuator, allowing operation as a standalone passive control. You can build the Sweetest Whispers as 15K attenuators, add some RCA jacks, a selector switch and a cabinet, and you have a very cost effective "passive preamp".

For use in the Foreplay the basic 15K series design is re-implemented as a shunt attenuator, often regarded as the most transparent sounding attenuator configuration, putting only one "padding" resistor in the signal path. This additional padding resistor may be chosen from among four values included with the kit, to give the nominal 19dB gain of the Foreplay preamp circuit (with Anticipation upgrade) a more flexible range of gain. You can choose from 9 db (close to being an industry standard), 3dB, -3dB or -12dB maximum overall gain with the change of one resistor. This allows custom tailoring of the gain chain for a broad range of unique system requirements like high sensitivity horn speakers or sensitive solid state amplifier inputs, or low input sensitivity single stage DHT amps and low output DACs.

Like the original Sweet Whispers kit the new Sweetest Whispers attenuators only take about 20 minutes to build. You get a photo and detailed instructions that explain exactly where each resistor goes, and the finished attenuators install in a manner very similar to the stock pots. For installation in a Foreplay you will just need to drill a couple of 1/8" holes in the chassis (we include an easy to use drilling template) and do a bit of rewiring of the ground buss once you remove the stock pots. 

OK, OK but is this thing really any good? I mean, how can it be any good at all for $179?

This is a very dicey question for us to answer. Sure we think it's great, but the harsh reality is that we would be called charlatans and snake oil salesman by some if we started spouting superlatives. That is the nature of the audio business. Maybe the best answer is that we sell several hundred Foreplay kits every year, and that they almost never turn up for sale used on E-bay.

We will let folks who have built the Foreplay speak for us. These are various posts from the Bottlehead Forum and Audio Asylum that we have seen through the past year or two, along with a few letters and e-mails we have received. Remember, we didn't write these, the opinions are those of the builders-

Comparison of Foreplay with high end pre-amps

Posted by coffeedj on September 04, 2004 at 21:15:57

I had a need for a second pre-amp recently, so I went to my local used Tube stereo shop to see what he recommended. He had a PSE HL-1 Tube hybrid Preamp, BAT VK-5 Tube Preamp, and a few others in the $6000 range. I tried them all and found that the Foreplay was better. I was stunned!

The foreplay was not a lot better than the $6K class devices, but still audibly better. I didn't believe it and brought my wife in to do a blind A-B test (she is a musician). She agreed that "A" (foreplay) was slighty better than "B" -- the competition. It was more open on the high end, faster on the transients, and had just slightly better presence. The telling point was listening to cymbals, violins, and a blues sax. The foreplay was just more realistic.

Bottom line--I'm buying another Foreplay to build up. Now, to be totally honest, I modified the Foreplay with an external power supply with DC heaters, and isolation transformer. I also used the anticipation upgrade and a Transcendent sound stepped volume control. But it is still better than anything I can afford to buy. My total cost was less than $300. WOW!

In addition, I'm going to pick up the Bottlehead phono-amp. My guess is that it will sound better than my existing EAR 834L. 

Norah Jones is singing in my bedroom!

Posted by Corndog71 on March 19, 2004 at 22:27:53

I don't quite know where to start. I'm freaking giddy as hell though because I hooked up my new Sweetest Whispers as a 15K series attenuator.

First a little background. Earlier today I discovered a new HIFI store in town. I got to listen to a couple of rigs worth more than a Ferarri. While listening to them all I could think was that they simply sounded effortless and got the hell out of the way of the music. They didn't make either of my systems sound terrible, just unrefined. Like they were soo close but just lacked the delicacy and grace.

Skip back to my tonight. After my portable MD player died recently I decided to move my Rega Planet (first version) into the back up stereo. It's been nice hearing CDs through tubes. I've long known my NAD 304 (playing preamp) was a weak link and desperate to be replaced. So I recently bought a Foreplay. (Thank you tax return!) Knowing I'd want to add mods to it I later ordered Anticipation and, when they came out, the Sweetest Whispers. My Foreplay isn't due until next week so I got antsy. I already had a little home made switchbox in my "A" stereo for switching the audio of my Playstation2 and Xbox without changing cables. I just drilled a couple more holes, soldered in the SW and hooked it up in my "B" system.

SHAZAMM!!! Best $40 I ever spent! EVER!!
And now Norah Jones is singing in my bedroom! I can feel the music better now. Like when drums are struck I can feel them. I can hear the shimmer and fade of the cymbals in a way I never could before. My "B" system just got more refined!

Thanks Doc B.!

Rob C

Sweetest Whispers

Posted by mrclassicman on March 17, 2004 at 03:18:52

I received my kit yesterday, took off work early so I could build and install them. Being a heavily modded 4play with caps that you could jump start a car with access was the only real issue. The 4play looks stock from all sides, kind of wanted a "sleeper". The Sweetest Whispers worked great in the shunt mode. They seem to have added at least a layer to the depth in the sound stage and much more detailed instrumentation. The individual instruments are more separated now. It is wonderful picking out specific items to follow when listening. The mod was a great addition to what is becoming a very refined piece of equipment. Thanks Doc, Eileen, Voltsecond, Paul and all others supporting the forum, and the products. I myself would not have been able to get so far in this journey as fast as I have with out you all.

Terry

Newly installed Foreplay Anticipation- Wow!!!

Posted by tcell on August 15, 2001 at 09:58:39

Hey all!

After about 3 months enjoying my Foreplay (stock except for 3.0uF Hovland output caps) I decided it was time for the Anticipation. Oh my goodness, what an upgrade!!! I was skeptical that I would be able to hear the difference- being somewhat sonically challenged by too many years in high school rock bands- but I'm just blown away by the increased transparency, better imaging, more 3D-like soundstage and tighter bass.

To anyone considering building a Foreplay, I say absolutely, but even more I encourage you to build it stock first and listen for a few months before modifying. Then you'll be as blown away as I am with the inexpensive Anticipation upgrade which takes the awesome Foreplay to a new level.

Man, I haven't even started messing with the stock volume pots yet!

Thanks Doc B., and my buddy Chuck!

Re: Newly installed Foreplay Anticipation- Wow!!!

Posted by johng  on August 15, 2001 at 15:44:42

Your foreplay sounds the same as mine - I built the stock foreplay first (except I used Doc's magnet wire throughout and gold jacks). I kept the unit stock for about 6 months, so was very familiar with the stock unit before modifications. First upgrade was the 3.0 mfarad Hovlands - this seemed to improve bass performance and improve the overall sonic signature (smoother, a little more natural sounding).
Next upgrade was Anticipation and WOW! I could not believe the difference! Bass was stronger, tighter. I could now here more distinctly each instrument, as if they had "separated". Overall clarity improved alot.
I am pretty satified with my foreplay now, so I am moving on to focus on other parts of my system, which is:

Foreplay
Paramours (with some upgrades)
Jericho Horns with Fostex 208s drivers
Various sources, analog and digital.

I told my wife earlier today that I am finally getting the type of performance I expected when I started this journey. The overall sound now is much like the Acoustat Monitor III's that I owned and loved several years ago, but with much more detail, a "blacker" background, and much improved dynamics ( a kick drum you can feel ).

Buena Suerte!

John

Paradise found!

Posted by vanbeat  on August 14, 2001 at 06:58:54

After more than nine months of trying to get a tube rig together - which started with a (amp name withheld) and a pair of DIY tqwts - I think I've finally got everything that I was after. The (amp name withheld) was eventually returned and replaced with a set of Paramours, which join my Foreplay, Tjoeb 4000, Fostex Horns, PE Titanic sub, Hitachi HT45 turntable and RS phono stage. I came into this game not knowing anything about tube hi-fi, but with the patience and friendship of Ed Schilling of the Hornshoppe, I was able to weed out the weak links (see above) and wade through intricacies of it all and come out with a system better than anything I've ever heard. As trite as it may sound, I really am hearing my old faves for the first time again, and really can't believe some of what I'm hearing...
Anyway, I just wanted to take a minute and introduce myself and thank everyone involved with Bottlehead and the board for all the help and incredible gear you've provided. You'll no doubt be hearing more from me.

Stoked like hell,
Van

Sex at Dawn.... "Feels Like the (Real) Time" (initial FP report)

Posted by G-Man on June 24, 2001 at 12:26:08

Well, I fired up my FP the first time this morning. After quickly figuring out that I needed to ground the FP chassis to my power amp, things went very smooth. Popped Jack Jezzro’s “Jazz Elegance” and sat back to enjoy the show. This is for the most part a bare bones FP. Isolated gold RCA’s, G.E. metallized poly coupling caps (2.5uF) and a Bob Crump power cord are the only mods to date. The tubes are a pair of $7 Valve Art 12AU7’s I bought to spare the Clear Tops from a possible early death due to “user error”. The Clear Tops and 2.2 uF MusiCaps go in as soon as I’m comfortable that there aren’t any initial problems.

Without any break-in period to speak of and at only moderate volume, the sound was breathtaking. I’ll spare you my lame attempt to describe the sensation, but it was simply the best sound I’ve ever heard from my system. After a few songs, my analytical brain woke up and started dissecting things. I’ll post a couple of specific technical questions that I need help with.

So far, so good. Thanks again Chiggy!

congrats...

Posted by chiggy on June 25, 2001 at 15:17:59

Hey G-man,

glad to hear you're enjoying your fp. just wait until those mods start to roll into your chassis. the caps will add something missing from the sound...cleartops will add definition and a nice soundstage...SW's will give you control over the volume + some clarity, and the anticipation is gonna blow you away. Just remember to take it one step at a time and get familiar with the sound to see what simple circuit and part changes do to the sound.

I didn't think it would be worth all the extra desoldering and considered installing everything on the first go around, but it has been more than a great experience.

again, congrats on your new baby. have fun troubleshooting....I love the rush of new parts and potential changes on first fire up. I keep telling myself I should have been a Microsoft engineer. oh well.

regards,
chiggy

New Foreplay has entered the world

Posted by plantman on June 26, 2001 at 22:59:48

 

Thanks Doc and company. I finished my Foreplay tonight and WOW, all the test measurements were correct the first time. It is at this very moment breaking in and the hum is only noticable up close to the speakers when I crank my amp.

The mods I included were Auricap output caps, Sweet Whispers, gold plated tube sockets (I chose a gold color scheme), transformer housing, vibration dampening for the transformer, and I am currently fabricating a new wood chassis.

This was the first electronic kit that I have ever built and it worked the first time I applied power to it. The instructions were clear and the process reminded me alot of building airplane model kits. Take it slow, read and reread the instructions and you can't wrong. A lesson I learned quickly was to give the solder time to flow and you will get a good connection everytime.

I want to mention that the contributors and question seekers were invaluable for providing answers to my questions. Searching the forum archives provided the answers to all of the questions I had during construction. I want to thank all those who have helped me without even knowing it.

Does this make me an official bottlehead?

Plantman

This Foreplay is a LOVE Child !!! Doc, see ?....no Hum, very quiet

Posted by Nutube on June 23, 2001 at 23:00:50

For those who are afraid to dive in and have ZERO electronics background Do it!! The reward is fantabulous. So many will help you on this forum.
This child hasn't teethed yet still it is so quiet and smmmooooth.... the C4s are not even in, stock everything except for Sweet Whispers and Voltsecond's Tranny shock absorbers..
THANKS to all who helped especially Doc, Gary P. Voltsecond, Quest
and so many on the forum. Sorry if I missed your name.
Last time I felt like this was when I peeked through the glass window at the pediatrics ward and saw my first born!
Actually I had to take it to GARY P. he gave it a once over, found/fixed a few minor mistakes( forgot to solder and burn off one wire and hook one wire to wrong terminal on right side step attenuators) and we fired it up with his Battery driven home brew amp...Sounds great> Gary thanks a million.
We also used the selector and added resistor to input 1 and 2. Now I have 2 sets of inputs with slightly lower db
After building the Parglows, will audition then will add the C4s
The tweak is on!!!
What would upgrade to Solens provide? bigger deeper soundstage?

Would upgrading tubes achieve that too.Just trying to decide which first.
Again thanks... "la de da de dah la de dah .... :)

Wow! Foreplay success for a true virgin!

Posted by ZenAudio on March 11, 2001 at 21:58:34:

Well, I just built my Foreplay today. Had no real electronics/soldering experience whatsoever, but must have been lucky because everything passed with flying colors -- although my "live" measurements were all a little high across the board. Just hooked her up to my NAD C370 and was STUNNED to hear that it improved the sound noticeably. Come on, a $100 buck kit built by a true novice, beats the preamp section of a highly-rated integrated. I just sold my entire high end rig to my friend. I had the Rogue 66 which was a nice piece and the Foreplay is right there. I'm a believer! I'm ordering my hot-rodded Foreplay tomorrow. Then the amps! By the way, this whole bottlehead community is one of, if not the, best site on the web.

Mike

It's a beautiful thing, man...!

Posted by danshifi on February 01, 2001 at 22:24:11:

...the sound I have coming from the other room! I finished assembly on my near-stock Foreplay this evening! I purchased the "whole deal" kit but assembled it stock first (with magnet wire and gold RCA's), and it is sweet...getting sweeter with each new track!!
I'll likely add the sweet whispers very soon as I do have crazy hairtrigger volume pots with my 200WPC SS amp. I hope to hold off for a few weeks on the anticipation mod, just to appreciate it more. This thing is already the best pre I've had in my system before. The Hype is Real!!!
Hat's off to Quest for his website and answered questions. Many thanks to others who gave me advice in the past few days. A great big thanks to Doc B and crew for the products and service! I'd like all to know the service I recieved. My kit was missing one 1.8K ohm resistor and the local RS does not stock that value (order only). After letting Bruce at Bottlehead know of the shortage, they sent a pair of them out to me. Priority mail cost them $3.50 to send me $.15 worth of parts. Big thanks fellas!!
It's only just begun....

Posted by npsor on February 02, 2001 at 11:27:21:

Deja vu! I've had my Foreplay up and running about three weeks now and can't believe how it's made my meager system come alive.
The Bottlehead guys have rescued me twice now, once when I fried my power switch and then again when I needed new resistors for the sweet whispers I installed. I highly recommend reversing the position of the first two resistors in the attenuator for this kit. You get a nice low level position, a 5 db jump and then regular 3db steps. It really eases that first step from mute for those using SS amps.
Can't thank the good Doc and Bob enough for their help.

Nels in Bellingham

Foreplay vs. the high end

Posted by Mikey  on December 29, 2000 at 14:11:46:

Hi pol,

Up until a few months ago, I was using a CJ PV-10AL in my office system, along with a Rega Planet CD player, Dynaco ST-70 amp, and some DIY Vifa 2-way speakers.

I decided to give the Foreplay kit a try, figuring I couldn't go wrong considering the price. Sure enough, right out of the box the Foreplay ousted the CJ from my system! That same day I listed the CJ preamp on the various used audio websites...

Over the course of the next two months, I converted the volume controls to shunt operation, replaced the coupling caps with Solens, and added the snubber. The thing keeps getting better! I have the anticipation mod on order now, and can't wait to try that when it arrives...

I would urge you to give this preamp a shot. It's fun to build and sounds great! You will also have the support of all the people who frequent this forum.

Mikey

 

Posted by RBP  on December 29, 2000 at 19:20:59:

Just Proves that the Foreplay is "badd to the bone". I sold an Audio research SP15 !!! Foreplay now has 3000 fine hours on it.

RAWHIDE !!

 

Posted by Paul D on February 09, 2001 at 10:34:16:

And it is much better than the CJ PV-10AL that it replaced. The CJ in comparison sounds rather murky no matter what tubes I had in it, and the dynamics of the foreplay are much better. Changing the tubes on the foreplay and doing the upgrades should make it that much better.

Paul

Posted by Tony D. on February 09, 2001 at 11:18:54:

In Reply to: Foreplay vs. Balanced Zen posted by bmunson on February 08, 2001 at 19:48:03:

 

Hello Ben, I am the fellow who e-mailed you regarding the boards for the Zen Balanced Linestage. I have directly compared the Foreplay to the Bride of Zen which is not the Balanced version but has the family sound from what I am told and I think the Foreplay is better.

Definatly more musical and there is no contest in the midrange and highs, the only place the Zen pre-amp was perhaps a bit better was in the bass but I think the C4-S mod. to the Foreplay will address this issue so all in all I have to say go with the Foreplay.

You also have the Bottlehead forum as resource centre if you build the Little Linestage that Could.

Take Care.

Tony D.

 

posted by rev on November 20, 2000 at 11:27:33:

 

On Sunday I finally found the time to finish my Foreplay kit. Before I begin the usual glowing review, I wanted to express my sincere thanks to the participants of the Bottlehead forum, particularly, Quest and Voltsecond. Without your advice and assistance, I probably wouldn't be listening to my Foreplay yet, and I certainly wouldn't have had such an enjoyable time building it. Thanks to your freely offered assistance, however, my family and I were able to spend part of an enjoyable afternoon listening to music through a fine little pre-amp.

So, here's my glowing review. Mind you, I am not really an educated listener, but I was more than satisfied with what I heard.

I hooked the Foreplay up to my fathers unmodified SS Haffler DH2xx amplifier. My father built the Haffler some 20 years, and it still sounds fantastic. We listened to two different sets of speakers, his pair of Maggie 1.4s, and my own recently completed RS-1354 full range TQWP's (based on Weem's plans). A Toshiba 5109 DVD player was used for source. Subject material included some Yo-Yo Ma, Johnny Hartman/John Coltrane and Duke Ellington/John Coltrane.

We didn't really have time to do an a/b comparison with his Haffler pre-amp, so I can only comment on the sound of the Foreplay. The Maggies were a treat with the Foreplay. To my ears, bass was excellent, even though the Maggie 1.4s are usually week there. The Maggies traditional strengths, fast transients and incredible detail were really enhanced with the Foreplay. Details such as breathing on the sax were easily heard. My mother has those fabled "golden ears," and her comments tended towards "wow," "sound's great," and the like. My father chimed in with "really open, detailed sound."

The RS-1354s probably sound as good as any pair of $100 speakers can sound. I built these speakers for the fun of it, and they are fun, but they have limitations, particullary a dead high end, and muddy bass. With the Foreplay in, the muddy bass seemed to clean up a bit. I think only a super tweeter will lift the high end.

Thanks again to all of you. I am definately hooked on DIY tube gear now. Happy Thanksgiving!

-rev (Paul D)

After a long wait I received the Foreplay kit and assembled the preamp last weekend. After I got it up and running I gave it a listen and I have to tell you that I thought it sounded great although maybe a little harsh compared to what I am used to. Then Monday evening I installed the Anticipation upgrade and now I am hooked on this little box. What a great sounding unit. I never claimed to having a "Golden Ear" and I laughed a most of those who did but I can tell you one thing. This is a great sounding preamp even if it is a kit and costs under $200.00. I have 3 other preamps in my home (AVA, Mc) and this one sounds just as good. I have been using the Foreplay thru an AVA modified ST-70 and I think they are an exceptional match.

I am not an electronics wizard and frankly most schematics lose me but I do like audio and it has been my hobby for many years. I started building some simple kits to partially educate myself in this area. Your Foreplay kit was simple to build and the instructions were straight forward. Thank you for a neat little DIY. The best thing is it sounds so good that

I will actually use it. I am a woodworker and I built a nice walnut base and went to Radio Shack and picked up goldplated RCA’s so it also looks very nice.

I am sorry that I cannot recommend this kit to everyone. Most audiowhatevers who spent 5 to 10+ times the cost of a Foreplay on a preamp could get pretty upset. Everyone else would be OK.

Anyway I just thought I’d write and say how much I enjoyed your kit and how nice I think it sounds (for whatever that's worth). When I get the urge to fire up the soldering iron again I will be in touch and I somehow don't think that will be too long.

Thanks Again

Bob Arshem

South Dakota

A friend built the standard Foreplay and several of us who have heard it were astonished with what Doc. B. is selling for ~$100 USD (now $149). The basic unit had a bit less bottom end than my BAT VK-3 but is very musical. I believe that the upgrade addresses the *slight* bottom end deficiencies. If memory serves, part of the upgrade involves a current source feeding the cathode. There are many who don’t like cathode followers and I don’t feel qualified to discuss this matter technically, other than to say that it lowers the output impedance so you can interface the unit with more amplifiers and/or drive long cables.

BTW, we fed my Welborne Labs Moondog / 2A3’s, which I believe has a 100K input impedance.

If forced to rank the following 3 linestages, I’d place them in the following order:

1) My BAT VK-3

2) The Foreplay

3) Audible Illusions Modulus 3

This is my *personal* opinion, so all of you happy Audible Illusions owners out there, "don’t worry, be happy".... :-)

The unit travels in nice company at a steal of a price. The price is an added bonus.

Regards,

Thom Mackris

Doc B.

First, let me thank you for the prompt and timely shipping of my Foreplay preamp kit. It arrived with all pieces intact and accounted for, exactly as I had the time necessary to begin the building process. Second, I would like to say that the instruction manual is EXTREMELY thorough, and flows from start to finish very well. I did find one minor omission,

and that is to solder both connections of the resistor from A3 to the left hand terminal of the left volume pot. Another recommendation I might add is to specify the exclusive use of 22 gauge hookup wire, as the ground buss (terminal 14) gets crowded very quickly. Other than the above comments, the final check-out went well and I was finally able to place the Foreplay in my system this morning. I’ve only got three words to say about the sound, "OH MY GOD!". I will highly recommend this kit to anyone who is looking for a simple line stage. I would say it is nearly every bit as good as the Audible Illusion L-1 I had here last summer for demo, and at 1/10th the price.

Thanks very much for the wonderful product. It’s helped me greatly with my soldering, as well as my follow-through (I’m notorious for half-finishing projects).

I’ll probably be ready to tackle the S.E.X. kits for our anniversary.

Thanks very much and regards,

Thomas Martin

Hi all,
Got my parasex and foreplay up and running last night! Oh my god! How can they provide this level of sound quality for so little money? I've only hooked them up to a cheap denon cdp and a pair of $100 Technics speakers I had laying in the basement. The sound from these less than state of the art speakers and cdp was sweet, detailed, very wide and full. Tonight, I'm taking some of the "good stuff" from the upstairs system to see what these little amps can really do.I'm looking forward to inserting my Rega Planet and Magnum Dynalab Ft101A. Couple of speaker choises to consider. I have a pair of Totem Arro's but this probably won't work well.[4 ohm, 85 db] However, I also have a pair of Infinity Overture 2 speakers [8 ohm, 96 db] that will rock the house with these amps. For the price of a mid-fi av reciever, I got a pair of powerhouse 5w mono amps and a line pre that sounds better than a whole lot of much more expensive equipment I've heard out there. Thanks Bottlehead, you may have finally cured me of spending way too much money on my need for music to stir my soul. I feel I've been ripped off by hi-end manufacture's for years, now I feel as if I've stolen my new amp's. DIY audio is the only way to go, just sorry it took me so long to find out. Thanks again,
Merle

Re: How does the Foreplay Preamp compare with the Audible Illusions M3A?

i dont know about the 3a but i think its a bit better than my 2b
a bit more open and more air on the top. we need dan to get a phono stage kit going soon. put a nice pair of mullards or bb in that puppie and enjoy.
i dont know if the kit will help you build off a schematic though
the kits have all the routing of the wire figured out for you. try the sex amps with the opt upgrade next thats a killer combo. dont let the 5 watts scare you it will drive most speakers in the upper 80 range to a impressive sound level
spaaaz

RobertP

My hunch is that the Foreplay will, 20 years from now, be revered as an everyman's component; a classic circuit well within reach of working class losers like me, kinda like Heath, Dyna, and Eico are today.

-niel

Foreplay vs. passive

Hello,

I was using a QED passive volume control for the longest time, while I debated the active preamp thing. Cost was a major factor as good commercial preamps that don't set you back sonically will definitely set you back financially. I decided on the Foreplay and simply would not go back. The Foreplay is a rare animal (low cost and great sound) and was just the ticket.

Not to totally trash the passive - it is dead quiet and does vocals really well but there is something missing over the Foreplay. Better bass and a smile on my face. I know that passives have to be done correctly - and maybe I wasn't there yet, but good low capacitance cables alone would buy 5 Foreplays with upgrades. When my Foreplay was dead stock, I preferred it. With the upgrades, it simply gets better. The Foreplay is, I think, 1/3 the costs of the Creek - sounds like a fun experiment.

SteveH.

What I can say with surety is that I have place my Foreplay into 3 different digital systems from midfi to megabuck and the sound has improved all 3 times.

Before I got my Foreplay I was playing my ceedee directly into my power amp and I thought that placing another component into the chain would muddy the waters. But oh no, the life was put back in the music.

I think the Foreplay makes the ceedee sound more like records playing in the best sense of that idea.

Tony D.

The ONLY problem with the Foreplay kit . . .

These are wonderful preamps that greatly exceeded my expectations, went
together quickly, fired up the first time and shamed my rodded Dyna and
Quad 34 preamps. The only 'mod' was that i used 99.99 silver for all of the wiring. The CS4 mod finally gave my MMG's solid bass. A nice, unexpected surprize. Almost like a free gift.

Highly recommended piece, I can hardly wait for it to break in!
Doc and associates, i'm very impressed.
thanx

Byron

Aside from the solder fumes, I've found building the product to have uncanny parallels to its namesake:

1. They both keep you up at night.
2. You sometimes wonder if you're doing it right.
3. The tighter the coupling, the happier you are.
4. Your s.o. does not always understand your urgency for it.
5. When you're not doing it, you think about doing it.

Apologies in advance!

-v

Considering Foreplay...would it match in my system?

I just finished my Foreplay wired with the magnet wire Doc recommends. I have not added the anticipation upgrade yet--just built it stock. I am using it in front of a SS 200 WPC Adcom power amp with monitor audio 5i speakers and an old sony cd changer. The sound is a definite improvement over my adcom preamp. It sounded great with everything I played but when I put on Ella Fitzgerald and Joe Pass' Speak Love CD, Ella was standing in the room. Better imaging, better transients and better low level resolution and I am sure it would offer a similar benefit over your Hafler preamp. BTW this was my first attempt at an electronic project other than 25+ years ago as a kid putting together a simple heathkit which didn't work and changing out an electric guitar pickup( requires soldering like 2 wires). The instructions are so straight forward, it worked right away.
Good luck
Kyle

I would use the -20db to -50 db stepped attenuators though, as a big SS amp might need more than the stock pots or 0 to -30db.

I have my foreplay up and running with all the mods, three conductor 12 gauge twisted power cord, and it sounds as good as anything I have ever heard. I am using a powered sub FWIW.

Nick

Start by building a basic Foreplay; then add the Anticipation upgrade and finally change the volume controls. You will notice sonic improvement with each change. Check out the web site "Quest" provides to aid Foreplay construction. There you will find all sorts of useful tidbits, including help with soldering technique.

It's obvious that, except for deep bass, you like the speakers you are using a lot. A possible answer to the bass issue is a powered subwoofer.

Eli D.

Afraid to get started

I was where you were just over a year ago. Now...

I'm reaching unparalleled heights of sonic bliss with the Foreplay and ParaS.E.X. amps I built myself from Doc's kits. You can do it!
Stephen Hayes

After you build your foreplay, you'll wish that everything was as easy, inexpensive and good as the Foreplay. (If only ET made cars and computers....)

The most important skill in building these things is patience. As a bonus, you have this board to bounce your questions off of. There are a lot of Foreplay builders here, and they've answered all manner of technical-difficulties questions to date.

Give it a try. You'll have fun.

-Neil

---Scott

Another satisfied Foreplay builder

Stuart Smoot

And last Sunday I was at my friend Keith's house where he was trying out a Meridian 508 ceedee player, Medowlark Kestral Hotrod 'speakers, YBA amplifier and the good ole Foreplay (with Anticipation, Sweet Whispers, Hovlands) as pre-amp.

The Foreplay was right at home with these megabuck components, and I think it tamed some of the more questionable aspects of the YBA amplifier and digital front end. Extremely listenable.

The Foreplay really sets the High-End, Big-Buck Bullshit mindset straight in my opinion.

Tony D.

Let it run upstairs for a few weeks to give it a chance to really break in. All tube gear needs a break-in period. Then do some critical listening and take it downstairs and swap it out for the ARC. Wait a couple of months and get the Anticipation upgrade. You'll be amazed all over again. Don't get in any big hurry on the upgrades and tweeks, you'll learn more if you go slow.
Where does it all end you ask?
I don't have a freaking clue!
I really sometimes wonder if the Doc doesn't just have us all HIPMOTIZED! 8-|

Bob Samuelson

Foreplay !!!!

I cannot say enough about how much I like the sound of my Foreplay.
After installing a new CD player in my system things have come to life in a big way. I decided to try out my old pre to see if everything would be as good. After several hours to warm things up I decided it wasn't going to cut it. After reinstalling the Foreplay the magic came back! It's really a fantastic sounding unit. Thanks again Doc, This thing works !!

Stock Foreplay with Snubber, C4S, Sweet Whispers, Braided power cable, NOS Radiotechnique 12AU7's.

Super Foreplay is in the planning...

Happy listening
Keith

Foreplay or AES AE-3 preamp- which is better

Some of the folks on the rest of AA board would have disagree with me on these but to me AE-3 is more "hi-fi" sound than being natural. If you have a very lean sounding power amp like SolidState and such but with very high resolution, nautral sounding SET amps like ParaGlows and my "Buddhafied" Loftin-White 2A3 things become very obvious.

You have to try Foreplay to believe it. With stock Foreplay with Sweet Whispers 12-step attenuators in place and RCA cleartops you get one of the best-sounding preamps that beats many tube preamps many times it's price. Adding Anticipation Upgrade to Foreplay puts many sub 2K tube preamps to shame (neutrality is the name of the game).

If you have some fundamental knowledge of  DIYing and such I would strongly recommend you give it a try. After all what can you loose for a $99 preamp? (DO replace the original with Sweet Whispers).

...

I'm not saying AE-3 is being "analytical". In fact they are more likely  "euphonic" than anything else. Terms that beginners would describe as "...smooth, warm tube sound...". However to my ears AE-3s with 6SN7 often add too strong a "flavour" to the sound. If you couple this pre into a fairly neutral-sounding power amp + speakers the sound will become overly obvious. (warning: it can be "bloaty at times).

On the other hand Foreplay is more easy-going in a sense that it is more "neutral-sounding" than that of AE-3. Those who own/build/operate a Foreplay can tell you that many of them (inc. me) play music many hours at a time. Smooth and easy-going is what I'm trying to say.

The reality in audio-sense is that any active preamp will add its own "flavours" into the sound. Passive preamp (no amplification stage, just volume control/attenuators) will be "optimal" but under certain conditions, optimization cannot be achieved.

Either way, a preamp is a difficult issue, both in terms of it's role in the audio chain as well as the sonic virtues. While I personally do not reject the idea of having a bit of "tube sound" in the preamp side, frankly I would prefer it to sound as "neutral" as possible.

Good luck and all the best to you ;^>

Quest

Doc B's Foreplay would probably not be an upgrade at $99(now$149). Wish he made one for about $600 or so.

The reason for this little preamp's performance is found in the simplicity and elegance of the circuit design. Remember this is the same pre that is used with Doc B's SE kits so you better believe it passes detail and musicality. I am very happy with mine without the upgrade which I will be installing very soon. The sum total will be $200 very well spent

Bill

I've just finished building the Foreplay preamp from www.bottlehead.com and am now building the paraS.E.X. amps. These are my first kits, I had a friend give me (literally) 5 minutes of instruction on soldering.

These kits are documented for beginners, the instructions are really clear and easy to follow. I've had no problem building the kits and have taught myself to use a multimeter along the way - if nothing else I use it to double check my reading of the color bands on the resistors. This project has inspired me to slowly work my way thru a very basic book on electronics. A few months ago I was just going to spend some $$$ on factory built tube electronics, I'm very glad I'm building these.

If you like working with your hands, I highly recommend it.

Cabro_man

I'm seventeen years old, and still a senior in high school. I had never even seen a soldering iron before. Now I have three wonderful pieces of equipment that are sounding absolutely beautiful, and I've saved a lot/learned a lot along the way. It was even a lot of fun to build them! You really don't have anything to lose.

Btw- I would definitely recommend the Doc B stuff. It's cheap, sounds great, and he's usually around to answer your questions. If I ever have a problem, I just give him a call, and we work it out.
Todd

I have to agree with Todd. I just built a Foreplay preamp, which I'm extraordinarily happy with, and have ordered the ParaS.E.X. amps. Look, I'm a technology clod -- and I successfully completed the preamp: it's that easy. And Dan Schmalle (aka, Doc Bottlehead) is extremely patient and helpful on the phone. Best of all, at $99 (now $149), the Foreplay is a painless way to see what the fuss is all about for yourself.

Jonathan Kranz

As far as difficulty, the most difficult part I found was in positioning the C4S boards - everything else was a snap. I would recommend installing the available upgrades as part of the initial construction, as there would be some hassles with things if trying to upgrade later.

When I get some time, I'll probably play around with the coupling caps and also look at bypassing/replacing the PS electrolytics. I may also order a 2nd Foreplay kit, and use it to build up a 'super' Foreplay, as some others have done.

Chris S.

Oh, how did the Foreplay/ParaSEX combo sound on the T-1s? Well, with 5 watts, they easily drove the speakers full range. Very detailed midrange with good tonal accuracy. Somewhat weak on the top end and deep bass when compared to the Atma Spheres full range, and not as effortless or full-bodied in the overall presentation. But they made music, and lots of it. And they proved again that the most important consideration in an amplification stage is circuit topology - before tubes, before parts quality, before any other consideration. Put another way, there's boatloads of expensive commercial gear that would be put to shame by $500 worth of preamp and amp.

Phil Seig

Check out the goodies (kits) from Electronic Tonalities (at his website www.bottlehead.com), like the Foreplay preamp (linestage) at $99.00 for the basic kit ( now $149), and several SE amp kits, with 2A3's, 300B's, etc. They are a great value, the instruction books are great, and they sound, to die for (IMHO)! BTW, I am a satisfied customer of Doc B., one of the neatest people in this business. This is not a commercial, but merely a testimonial, and I have no financial or other interest in ET.

Dear Bottlehead,

When I ordered the $75 Anticipation upgrade I felt stupid that I might be wasting money. For 8 hours, starting at 11:30 PM and continuing until 7:30 AM, I installed and trouble shot (reversed the diodes on the 2nd set of PC boards by mistake) the Anticipation upgrade to Foreplay. Then I tested for sound improvement...

My God!!!

This is the sonic dream that I've been looking for. The upgrade took this good sounding pre-amp and turned it into something that makes my system sound so beautiful that it is hard to describe. Now I know what they mean when they say "the piano sounds like a piano", "the amp sounds musical", and the other sorts of comments that high-end sound reviewers make.

My system is: a Cambridge Microworks sound subwoofer using its built-in 10 to 20 watt (they won't tell me the actual wattage) satellite-speaker-amplifier ($260) to drive NHT Super Zero speakers ($225) with the Northcreek ($85) crossover upgrade in the Super Zeros. My sources are a computer CD-Player (Apple 9600), a Mitsubishi Hi-fi VHS deck ($650), a Creek remote volume box ($200 from Audio Advisor), cable TV DMX digital music with its digital converter box ($18 month), and the Anticipation/Foreplay Pre-Amp Kit ($99 {Foreplay} + $75 {Upgrade Kit} = $174). To describe the new sound... Delicacy: There seems to be no degrading of the decay characteristics when hearing a snare drum and cymbal echo-decay with the unit installed in the sound path. This comparison was done both with and without the updated pre amp in the sound path using Marceo Parker's jazz classic "Children's World". Near the end of the song, decay and echo can be heard clearly (probably electronically created). I built a $100 pre-amp "effects" kit from a different manufacture and it destroyed the decay characteristics of this music. But the Anticipation/Foreplay handled the decay similar to a nude wire... passing the decay without shortening it.

For me this puts an end to the idea that a music source going direct into an amp is the way to go. This pre-amp,

apparently through its updated impedance characteristics, vastly improves the sound. I tested, with and without it, using my Hi-fi VHS player and cable DMX digital music as a source. With the pre-amp in-line the sound is much much much better.

One of my favorite pieces of music is Barber's Adagio for strings. I recorded it from CD onto VHS HI-FI a few years ago. With the new pre-amp update it sounds involving and beautiful like never before. The rest of the music recorded with it has always bored me, most classical does, but now I find myself liking it due to the improvement in sound quality. For the first time I listened to all the music to the end of the recorded CD.

When listening to Jazz music the Anticipation/Foreplay combination has lost the small amount of bass tubby-ness that the Foreplay used to have. I liked this romantic rich bass and was afraid to update the pre-amp and loose it. Further-more, the use of a transistor in the update circuit bothered me since I'm into the tube audiophile "thing". But I took the chance doing the update and now the bass better resolves different notes while apparently maintaining some tube smoothness (a small amount) plus it has absolutely excellent bass timing & note resonance but without the previous slight to moderate over-richness.

Speed: The Anticipation upgrade makes passages of music that use fast finger work stand out as more completely separate notes. It is thrilling to listening to them, an experience lost on most other systems I've listened to. Another factor I should mention is the Northcreek music upgrade (about 6 hours of work) for the Super Zeros. This upgrade installs some new audiophile-quality resistors and substitutes the thumb sized inductor that came with the speakers with a very heavy air core inductor that is the size of a small man's fist.

The upgraded speakers put the old ones, which sounded good, to shame. The new sound has a bigger soundstage, a more frequency accurate representation, and much smoother sound. The sense of musical timing of the speakers

improves such that music seems to bounce along in an organic fashion; gone is electronic deadness. Since I've made this update I've lost interest in buying a pair of the entry level Sonus Faber Italian jobs, which, if I remember correctly, sell for around $1,000 or more a pair.

Both the Anticipation upgrade to the Foreplay pre-amp and the the Northcreek upgrade to the Super Zeros have the similar affect of making the music sound more real, more like a live band, rather than like a microphone-sound-reinforced band.

I have traveled to 4 different cities and heard many high-end speakers including Wilson Watt Puppy and Grand Slams, Magnepan, Revel (the latest speaker of the month and beautiful sounding), Sonus Faber, Linn, Thiel (1.5's are great), and Lowther speakers. Also auditioned were amplifiers from Argon, Audio Research, Krell, Conrad Johnson, Sonic Frontiers, Levinson, Jadis, Cary, Theta, and Marantz plus much other equipment. Given this background I have developed high standards, especially after hearing the Wilson Watt Puppy speakers ($15,000) which are hard to surpass in terms of a smooth, sensual, room filling impressive sound; they are truly a sonic Holy Grail within the realm of speaker production.

Though I have not made a direct comparison to my local high-end stereo store's Revel speakers or Sonus Faber with a Levinson amp, I sure have lost interest in spending that kind of money ($7,500 to $30,000) given the fine sound I'm getting for less (using a $1,000 minimal configuration of my system which was listed previously). An improvement will no doubt be possible with a standalone amp which is not part of a subwoofer/satellite system; this I will try next.

It took about 4 long nights (six hours each) to produce the Foreplay kit and a nother 8 hours to add the Anticipation update kit. I previously had had some soldering experience but no electronic design experience so I relied on your directions to get the job done right. The voltage checks provided at the end of the build were helpful in giving me confidence and for trouble shooting the one mistake I made without having to make a phone call to Bottlehead.

I like the point-to-point wiring better than pure circuit board design; it is easier to solder than small highly populated circuit boards and easier to get a general understanding of what different parts of the circuit do.

Thank you Bottlehead for a great experience.

Tom McDonald, Knoxville, TN

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