My Paramount experience

[johnsonad]

A brief update:  The Triad chokes have been in for a couple of weeks now and I’m ready to give some impressions.  Mind you this may not apply to your system!   The soundstage is pushed back some which to my ears is a good thing, before things were moving too far forward for my taste.   I’ve increased the volume on average by 2-4 dB above normal listening and I’m listening longer with less fatigue than before.   There seems to be greater detail and I’m more attentive and drawn into the music.  The only thing that seems to be missing is a little bit of “air” (or distortion?) around notes which, I felt there was too much of now that it is gone.  The background between notes feels blacker than before.   All of this is good IMO and quite unexpected given how simple the mod was.   

Driver tube wise I’ve been using the stock GE 5670W the soft start kits came with.  It does everything I need it to at the moment and has very low noise and microphonics.   Once the MQ iron arrives I’ll start rolling again.  All of the parts are here less the iron to max out these Paramounts for 2A3 usage.  Hopefully Mikey gets caught up quickly

[Grainger49]

I think you have heard a number of things I heard as well at Paul's.  But soon after putting in the chokes we improved all the iron with MQ BCP-15 and all nickel output transformers which multiplied this effect by a large margin.

Next you need to buy a pair of Clarostat 10 turn pots, 4 resistors and a pair of tube sockets to bring the bias adjustment to the top of the chassis.  This is a mod of convenience rather than a sound improvement.  But you will never need to flip it over to adjust the bias on the driver tube (assuming you have the soft start board installed).

[jrebman]

Aaron,

Sounds lke a worthwhile mod, but one I'll probably wait until my speakers are done before I try it.

Grainger, just curious why you used a tube socket for test points when tip jacks are available very cheaply and in a variety of colors?  Or was there an existing tube socket hole that you could fill?

-- Jim

[Paully]

If there was a better option, we just weren't aware of it.  We both have had Dynaco's as our main amplifier in the past.  I think that that concept for setting bias is just what we had in mind so that is what we used.  We looked around for some other options but didn't see anything that really worked for us.  The tube socket kept voltages below where one could easily stick a finger so it was good enough for us and an 8 pin mini-socket fit.  So we used it.

[Grainger49]

Jim,

I knew there were such things but I didn't locate them anywhere.  I didn't use the search parameter of "tip jack."  The tube socket was used because initially we thought there were 3 or 4 voltages to measure.  We also had thought that a socket would allow us to measure the B+ directly.  Paul Joppa was uneasy with even a tube socket with high voltage on it all the time.

Turns out there are only two voltages to be measured.  As Paul Joppa configured it the two should be the same voltage.  This simplifies the adjustment to: measure between the two pins and adjust to zero volts.

[jrebman]

Sounds good guys -- just didn't know if there was a particular reason for using a tube socket, but I understand why now.  I'll probably "borrow" the idea when it's time, but as I have plenty of spare tip jacks, and only two are needed, well, I'd rather drill a pair of 1/4" holes, than one larger one -- things are going to get crowded in there anyway.

-- Jim

[johnsonad]

Well said Jim. The more mods we do the more crowded it becomes   I may do this mod too at some point but I don't roll tubes often enough to justify it in the long term. Thanks for the recommendation! 

Now if Paul would release the schematic with relays and film caps in the PS........ ;^)

[Grainger49]

We have completely hijacked Aaron's thread.  We ought to be in Paully's thread:

http://www.bottlehead.com/smf/index.php/topic,1635.0.html

[johnsonad]

As all good things must come to an end, so does my ownership of a great pair of Paramounts.  My Altec Model 19’s are going to make way for a pair of Quad ESL 57’s and the Paramounts are not enough for these difficult to drive speakers.  It is my hope that the new owner finds as much pleasure in them as I did.  These really are a great sounding amp which scales up nicely with simple changes.  I want to thank Paul, Dan and the regulars here for making my ownership of them a pleasure.  I still have other Bottlehead stages and look forward to more in the future.

Regards,
Aaron