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What tube type and/or brand should I use in my preamp to get a little more bass response? Current tubes are JJ E88CC. Thx
The JJ's tend to be on the warm side w/a lower sensitivity. You could try some EH-6922's w/have a higher gain factor and are also more dynamic. And the Genalex Gold Lion 6922's are excellent w/plenty of gain but they wil cost you about $45 ea. The Electro-Harmonix tubes run about $14 ea. :)
 

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If you think you're going to get a different FR from changing the tube brand then you're a fool.
 

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What tube type and/or brand should I use in my preamp to get a little more bass response? Current tubes are JJ E88CC. Thx

Bass response with those tubes (6DJ8/6922) suffers when the individual tube has a relatively low transconductance, which varies from one tube to the next. The brand is not a particular issue.

I get the best results with the Sovtek tubes purchased from Audio Research in Minnesota. I usually get 1000 hours or so with them before the transconductance and noise degrade somewhat.

They test all of their tubes on custom testers and reject a large percentage of them (which are then sold to other dealers...a lot of the cheaper tubes on
the market are Audio Research rejects).
 

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There are so many variations and brands of that tube its crazy
6dj8
ecc88
6n1p needs more heater current if I remember
7dj8 if your power supply can handle the extra draw
Amprex bugle boys are well thought of
Siemans 6922 is also well regarded
JAN can be very good as well

very commonly used...I would prefer NOS rather than new construction
 

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There are so many variations and brands of that tube its crazy
6dj8
ecc88
6n1p needs more heater current if I remember
7dj8 if your power supply can handle the extra draw
Amprex bugle boys are well thought of
Siemans 6922 is also well regarded
JAN can be very good as well

very commonly used...I would prefer NOS rather than new construction


"JAN" stands for "JOINT ARMY/NAVY' and is not a brand; it just means it is certified to meet a U. S. military specification. It can appear on any brand of tube
and really means very little in practice.

6n1p is a different tube and is not interchangeable.

The 6DJ8 was developed by Tektronix in the 1960s for use in their oscilloscope low-noise preamp circuits.

The 6922 is an improved version of that tube with more rigorous specs.

The 7DJ8 requires a higher filament VOLTAGE to operate correctly; there is no "extra draw" involved.

The Soviet 6H30 is a completely different tube with lower noise and superior performance that is now used by Audio Research and a few other companies
for their super-high perfomance preamps. It was developed in the 1980s for the Soviet missle guidance systems. It requires a different circuit design and
can not be interchanged with a 6922.
 

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No one has mentioned the 7308 tube, which is a direct replacement for the 6DJ8 / 6922.

I have done some tube swapping in a preamp between Sovtek 6922, older RCA 6DJ8, NOS Philips JAN 6922, and Amperex 7308. Liked the 7308 best, and that's what I have in there now, but the differences are subtle.

You certainly can't base the quality of the tube upon it's tube type. The 6922 is built to tighter specs, but that doesn't mean they will sound better in a preamp.
 
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