12AX7A and AT7 tubes


I recently changed all 8 power tubes (KT88) in my 8 year old Mac 2102 power amp. Used Gold Lion tubes as recommended by the majority of the Audiogon respondents to I thread I ran asking for KT88 advice. As suggested, these tubes really made a difference in the sound produced by the 2102. I am now thinking that maybe I should be replacing the 4-12AX7A and the 4-12AT7 tubes as well. I am pretty sure there is nothing mechanically wrong with the OEM tubes currently in the amp. but I am just interested in what this change would do for the sound, if anything. I have some questions about this move. First, do you think this is a worthwhile investment? Second, if this is a good move, what tubes do you recommend? Lastly, should I also change out these tubes in my C2200 preamp? If cost gets to be a factor, would you do the preamp first, last, or not at all? (As an aside, Upscale Audio recommends the Mullard CV4004 and CV4024. The CV4004 tubes are a whopping $80.00 each. Are they worth it?)
frepec
Tpsonic,
After telling you of these remarkablebtubes. Mind you not the absolute unamynous all time weorld best but a decent really cheap tube from the Sino conglomerate Shuguang, I can't souce them. So I ask where did you find them? To the original poster no other shu is worth your time it really must be their 12AX7C or 9th edition only. no more than $10 a tube. Mike Sanders of Quicksilver audio insisted that a new owner of the Triodes stick with the because he thought they great and voiced those amps using them. Our buddy Trelja was as skeptical as i a was which dictated extirpating the offensive terrible excuse for a real tube never mind a good one. It took quite a bit of convincing so just to make him stop harrsing me I said OK and paid 9 bucks for a pair of brand new 9th ed Sino branded Shuguang. And I would not be writing this novel if I wasn't floored by them. Shu has made more with the B or 8th for the biggest group of tube consumers the shreding electric guitar guys . It just didn't distort readily therefore useless for guitar and good for audio. Now they are gone.
I believe Dougs' tubes has them (8+9G).At least they did as of earlier this year.I sent two friends for them.I bought 8 matched off E-bay some years ago for about $5/ea.
Thanks for the responses. Some of you are asking about what kind of sound I like. I want precise sound, not flabby. I do not want thin highs that lead to listener fatigue. I like full sound stage sound that blooms. I do not want overpowering bass but do want bass that is full and rich. The Gold Lion KT88's really expanded the soundstage and gave the music more "presence." I would like to continue to build on that. I have read some reviews of the re-issued Mullard that say it is almost as good as the NOS version. Do you agree? Also, still interested in should I finish the 2102 before I go on to the C2200 preamp or do the preamp first?
Actuallly the price of a used pair of Blackburn Mullards, not re-issue, maybe a worthwhile experiment albeit expensive if the tubes are from a seller who will stand behind the product. The best current production is the Tung Sol either gold pin which many think is better than the steel pin. I like the steel pins just fine. However a warm expansive good condition real Mullard they are not. The Sinos have a bit of tipped up treble emphasis so you might not like it. Tpsonic I got mine for the same amountas you 2+ years back on epray and trelja gave me a pair or two. They don't burn in much do they! Doug is "out of stock" which is really a bad term he can't them anymore than the others. The reason is they were taken out of production.
Frepec finish the MC2102 and then later move to the C2200. In the MC2102 you have to replace 4 input and 4 driver tubes compared to 2 phono and 2 high level tubes for C2200.