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

Showing 2 responses by mechans

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.
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.