Preamp choices for the tube amps

what tubes in your amp????
mine have the valve art kt88
and a JJ12ax7's I dont recall the 12at7 tube. the 12ax7 is one of the tubes that we played with when Angelo was in town,
I agree with the same conclusion that he heard also. a tube that was supposed to sound better, but did not.
Bob had a good time with that one, on paper they looked and specked out the same, but sounded way different.
night and day. took all the highs out and smooshed all the sound into bleeaaach.

on my sunfire pre I heard the same thing, before I put some amprex tubes in, then the top end got way better...

tube rollin for you....

Did you say whether or not you were listening to vinyl when you noticed the 'lack of sparkle'? I noticed something similar when listening to LPs (using an MM cartridge) until I replaced the 5751 (12AX7) on the phono PCB of my Sunfire Tube Preamp. According to Bob, the circuitry requires every bit of gain available from the 12AX7 (the 5751 is a ruggedized 12AX7, but with slightly less gain, according to Bob; 30% less, according to Tube Depot), In addition, Bob told me that the frequency response on the bottom end was also slightly degraded when using the 5751 in the phono circuitry. Replaced with an Amperex 12AX7 and everything was cool.

Which 5751's were you using?

RCA, 1974 manufacture, NOS

I'm using 50's vintage GE 5 stars. They have a better top end than the RCA'S but still slightly rolled off. What I have noticed about using 5751's is cranking them past mid 90's db they seem to run out of gas.

Agree with the above advice.....RE-TUBE TIME!

My amps are running KT120's for the power tubes, and further listening with the Pioneer SC37 confirms the amps are not really the issue IMHO... I am going to replace the front end tubes on the amps and then roll the Sunfire back into the mix. If I still don't get what I am looking for, I will then look inside the pre.

I still need to replace the broken tone control switches, so I will replace the tubes in there at the same time.

I now have some Bugle Boys from 1961 in the 12AT7 slots and a nice pair of telefunkens in the 12ax7 locations. Can the 6al5 make a big difference?

Anyway, the sparkle is back on digital sources when running the SC37, and present but rolled off a bit when compared to their digital counterparts. I am looking at tubes for the Sunfire... holy CRAP BATMAN! To get the good stuff, it will cost an arm and a leg to re-tube this thing!!!

Can the 6al5 make a big difference?

I think these are just for the bias network, DC restoration. this tube keeps the bias at a set level, even when the output tubes are not all the same, age, brand...etc.
at least thats how I understand how it works.....

Bob did give me a few of the 6al5 tubes, so I may have to try them, I'll let ya know


so have you tried different at7, 12ax7 tubes?

Sunfire Tube or modified C-19

What about these guys...
http://www.tubedepot.com/nos-6922-tele.html

a grand is a huge sum of money to spend on tubes for me right now, but IF these will do the trick, I will probably pull the trigger.

wow that a lot of mulla....
for at7's
the difference on mine was very subtle, and knowing Bob the at7's my amps came with did not cost very much....

so keep this in mind, do ya know any body you could borrow tubes from to test with?

I wish I did... for the coin I could get from my Sunfire pre amd the cost of these tubes, I could have a Pass XP-10

John, you need to stop dicking around with that Sunfire and get a tube pre that will match your amps better. One of the Joule or VTL pre amps would be a good choice.

John, you need to stop dicking around with that Sunfire and get a tube pre that will match your amps better. One of the Joule or VTL pre amps would be a good choice.

John, you need to stop dicking around with that Sunfire and get a tube pre that will match your amps better. One of the Joule or VTL pre amps would be a good choice.

IF I was to get rid of MY Sunfire, I would buy anything EXCEPT what F1 recommends

John, you need to stop dicking around with that Sunfire and get a tube pre that will match your amps better. One of the Joule or VTL pre amps would be a good choice.

IF I was to get rid of MY Sunfire, I would buy anything EXCEPT what F1 recommends

WOW!!!!