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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Valve/Tube Newbie: Amp for PAS3

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Owner of several working DYNACO solid state pre-amps (PAT4, PAT 5), solid state amps (ST120, ST150, ST400) and speakers (A25 and A35), I got recently a Dynaco PAS3 in excellent condition (mint, no mods and sounds good to me when hooked to the mint ST120 it came with).

This is my first valve/tube preamp.

I don't want to purchase a $600.00 Dynaco ST70 amp to start with. I would prefer to hook the PAS3 to a small (budget) valve/lamp amp to hear whether I hear a sound difference before keeping or selling it.

I was looking at something like Gemtune APPJ PA1501A mini tube amplifier ($180) or similar budget and small-footprint better amp

Any advice, reviews, discussions?
 
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Owner of several working DYNACO solid state pre-amps (PAT4, PAT 5), solid state amps
(ST120, ST150, ST400) and speakers (A25 and A35), I got recently a Dynaco PAS3

All the Dynaco speakers work best with solid state amplifiers. The ST150 is probably
the better of the three amplifiers that you have, so try that one with the PAS.

Before you draw any conclusions about the PAS sound, the selenium rectifiers in the
filament power supply should be replaced with 1N4005 diodes (or larger). This will bring
the voltage back up to 12VDC on the filaments. It could be a volt or more too low now.
You can just parallel the 1N4005 diodes with the existing selenium rectifiers for testing,
but watch polarities.
 
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Problem is, a winky little amp won't be able to push your speakers, so there's no point.

jeff

Not true at all. I use < 10w amps all the time with a25's. Depends on room size and how loud one likes to listen. If the room is small a few watts can work.

That said I have a pas3x but I'm not a big fan. It's okay but not really special. Imho of course.

I have the gemtune el34 se amp. It's fine with the a25s if you don't need to hit 100db in your room.
 
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