“I hope everyone understands that the Paramount was designed for the 300B and 2A3; the 45 modification is not a standard thing. “ PJ
Acknowledged! But, the Paramount design is so good, that, like many other Bottleheads…..I want to do it all the same!!
So here is the system configuration:
Speakers:
Electro Voice Sentry IV-A’s ( 3 way horns, 102dB/1w/1m 400Hz, 3500Hz crossovers), will be bi-wired bass bins & mid/treble. The bass could use a little boost, but don’t want to fatten up the lower mid-range too much.
Line stage:
Smash with Smash-up. 2uF PIO output caps.
Current amp:
Paramount V1.0 300B 6CG7 driver, 4.0uF PIO output caps, stock iron.
Game Plan:
Keep current Paramounts, use for bass bins
Build V1.1 Paramounts, use for mid/treble
Available Iron:
BH-7 27H/76mA Plate chokes
BCP-15 50H/40mA Plate chokes (2 pairs)
TFA 2004 Jr. nickel pinstripe
EXO-45 all nickel
Line voltage is pretty consistent at 120-122VAC.
I can mix & match the iron between the old and new Paramounts. I can convert the old Paramounts to V1.1. I can take the old Paramounts back to 12AT7 for greater sensitivity/gain. Maybe replace the input load with a stepped attenuator to control/balance with the mid/treble amp. Lotsa’ output cap choices from 2.0uF to 12uF. PC-2’s in the old Paramount to do CLC?
Way too many options to decide empirically by listening to each iteration. So the thoughts of the collective experiences would be greatly appreciated!
PJ has made several posts about the Paramount V1.1 conversion, beyond just changing the cathode resistors from 2K to 3K ohm. Some of the recommendations were to specific circumstances, (Jim R & Paully). Some of his posts are linked in other discussions, but, since the forum upgrade, they lead to the dreaded “404 - Page not foundâ€. Sadly I could not find much more with the search function. If there are other changes please post!
Can the cathode cap value for the V1.1 45 amps be reduced from 47uF?
What is the minimum power rating that could be used for the cathode resistors? Would two 3k ohm 12 watt Mills resistors be sufficient?
Anyone's thoughts and experiences would be greatly appreciated!
Cheers,
Geary
« Last Edit: April 15, 2016, 02:27:09 PM by galyons »
VPI TNT IV/JMW 3D 12+Benz LP-S> Eros + Auralic Aries + ANK Dac 4.1 >Eros TH+ Otari MX5050 IIIB2 > BeePre >Paramount 300B 7N7 > EV Sentry IV-A
Thorens TD124/Ortofon RMG-212/SPU >Seduction > Smash^Up> Paramour 45 MQ >K12's