Pre Amp Upgrade

[mcaddie7]

Greetings all,

I currently use a Fully Restored Dynaco PAS 2 tube amplifier. It's in line with my (all restored) Rek O Kut table, Citation 19 Amp, and Snell Type K speakers. I'm finding that the Pre amp is the "week spot" in my setup as I don't like the tone controls. I love the way the Citation made my system sound when added, but sometimes I need to adjust tone controls which can only be done on my pre amp.

I have around $300 to spend and was wondering if a more modern:

Wiim Ultra or Fosi Audio ZP3 Pre Amp may sound better than a 50 year old mid range pre amp? I'm leaning towards to Wiim as it also has room correction which I'm finding is why I need to use tone controls in the first place as one speaker is directly next to a wall. Any thoughts?

 

[Lavane]

$300 is going to be a tough one. Unless you find a good deal on used.
If you don't want tone controls, there is a mod to remove the tone controls in the PAS tube preamps. Personally I would save up and buy an Aikido line stage preamp if you don't need tone controls. I built one from a kit that my son uses now, and bought another I'm using now.
Tubes4hifi sells one in kit or assembled.
Erhard Audio just recently sold his PAS kits business to someone else, but Holger should have a link on his site for them. The Aikido has me stopped looking for anything else. Most people that try them tend to keep them.
I used Erhard Audio's Aikido board kits including the power supply for the first one I built. It uses 12AX7 tubes. The one I ended up with uses 6SN7's.

 

[twiiii]

Now if you had another significant digit in your bank account I would have all sorts of suggestions. If I were you I would tough it out anothr few years while saving your monies. Then maybe you can find a 7C or C-22 or one of Citations pre-amps. The Marantz has the most forward sound when new and the Citation was kind of laid back with the C-22 falling in the middle. I think I preferred the tone controls on the 7C. I especially liked the two stage HF filter. The controls had the best feel also. But if it were me I would want a C-32 or 33 or 34 as I love the graphic tone controls, the full mode selector and the variable loudness control.

 

[pac1085]

A quick google search shows that the Citation 19 has a 30k input impedance. The PAS is designed to work with older tube amps like dynaco mk3 or st70 that have 470k+ input impedance. (Edit, manual says 100k) That's almost as bad as it gets of a match for this preamp.

It's well known that connecting the PAS to a lower impedance amp will cause major issues with the tone controls.

Install the new MOSFET buffer board from Dynakitparts and you'll probably be a whole lot happier.

Here's a comparison vid explaining it in more detail if you're interested in that stuff...

 

[Lavane]

A quick google search shows that the Citation 19 has a 30k input impedance. The PAS is designed to work with older tube amps like dynaco mk3 or st70 that have 470k+ input impedance. That's almost as bad as it gets of a match for this preamp.

It's well known that connecting the PAS to a lower impedance amp will cause major issues with the tone controls.

Install the new MOSFET buffer board from Dynakitparts and you'll probably be a whole lot happier.

Here's a comparison vid explaining it in more detail if you're interested in that stuff...

I forgot about that gizmo! Good idea.

 

[mcaddie7]

I forgot about that gizmo! Good idea.

A quick google search shows that the Citation 19 has a 30k input impedance. The PAS is designed to work with older tube amps like dynaco mk3 or st70 that have 470k+ input impedance. (Edit, manual says 100k) That's almost as bad as it gets of a match for this preamp.

It's well known that connecting the PAS to a lower impedance amp will cause major issues with the tone controls.

Install the new MOSFET buffer board from Dynakitparts and you'll probably be a whole lot happier.

Here's a comparison vid explaining it in more detail if you're interested in that stuff...

My god thank you. I think this is the case of there being TOO much info out there on this pre amp. I’ve read several hours of forums and not once did someone suggest this as a fix when I explained my gear. Easy fix but for now I’ll be putting in the proper resistor vale for my C19 and see how that fairs but that video describes my exact issue.

 

[Lavane]

My god thank you. I think this is the case of there being TOO much info out there on this pre amp. I’ve read several hours of forums and not once did someone suggest this as a fix when I explained my gear. Easy fix but for now I’ll be putting in the proper resistor vale for my C19 and see how that fairs but that video describes my exact issue.

With anything Dynaco, there is so much into to slog through.