I need a lower gain 12au7 for Mastersound


I recently purchased a Mastersound Due Venti. It has 2 JJ ecc82 gold pins in the preamp. I find them to be a little high gain for my tastes. They do sound quite nice though don't get me wrong.

Could anyone recommend a 12au7 or variant that naturally has less gain than the JJ but still retains quite a lot of detail and low noise? New or NOS, doesn't matter to me.

Any responses or suggestions would be greatly appreciated!
Or if anyone has a Due Venti maybe they could let me know what preamp tubes they prefer?

I'm running it with a pair of La Scala's, they're just a little too efficient maybe...

Thanks for your time!!
ddderek
Ddderek,

I've found el34's- the Winged C, actually, to be "noisy", with a hiss at idle even with the volume turned all the way down. That, however, was on a Golden Tube Audio amp, which don't have the best build quality. MastersounD is in a different league.

I don't know if it's your drivers or the power tubes. What I do know is that MastersounD amps don't usually do this sort of thing- they are of high quality. My Compact 845 is dead quiet with 97 db/w/m speakers.

What I can do to help rectify the issue is this- I don't use the preamp section on my Compact 845. I use it as a straight power amp. Hence, I took the preamp tubes I bought for it- Telefunken smooth plates- out and tossed the Electro Harmonix back in the amp. No sense running the Telefunkens if they're out of the circuit.

So....if you want to try out a Telefunken 12au7 and see if the hiss goes away, let me know. Fire me an e-mail through Audiogon. You can try mine. If they work, great, you can then get a pair yourself and send mine back. If they don't eliminate the hiss, send them back to me, knowing they're not the issue. When I did use the Compact 845 as an integrated with the Telefunken tubes, it was dead quiet. No hiss. So, I know these NOS tubes are not defective. Let me know.
Found an old Westinghouse 12au7 kicking around in one of my boxes, put it in..... right channel has almost no hiss at all.
I have some pairs of Telefunken smooth and ladder plates which have lots of detail but quiet.
Follow up number 2!

Destroyed all 4 SED EL34's in the amp. The bias was way too hot when I got it and I never checked, thinking it was auto bias. Every tube was red plating with in a week.

Contacted the Italians and they were kind enough to show me how to bias this older "Semi-automatic bias" amp???

They sent pictures and everything. Very nice people.

Bought a matched quad of the EH 6CA7s last week, biased them to "no more than 6VDC" (I'm still not sure how this stuff works...)

Everything sounded beautiful. Way better.
The hiss was cut in half as well.

Then I ended up finding a guy on eBay from Moldova selling NOS RFT ECC82s matched pairs for $10 a tube...(sketchy?)
Many people on tons of threads recommended these German made tubes as the quietest tubes you could find and one of their favorite 12au7s for detail and value.

Got them today, plugged them in and Wow!

I can turn the amp to top volume and I have to stick my ear right into the squawker of the La Sacala's to even hear a slight buzz.

And for detail, they blow the JJ Golds away! Even after just a days listen.

Maybe I'm just too excited about the whole thing and posting too soon. But I PRAY that things stay this way!!

Thanks very much for all the help you guys!
Very Very appreciative!

Thanks to Viridian as well for lots of good advice keeping me a little more sane.

Thanks

Regards
-Derek