NOS tubes for Sonic Frontiers Line 1

In my system the Siemens CCa sounds best. To think I tried to sell them. Compared to the orange label USA made Amperex 6922 PQs the CCa is cleaner, quieter, more air, larger sound stage, deeper tighter bass. I cannot speak for how they would stand up to the early 60s white lable PQ 6922 USA made tubes. This is after 50 hrs on the CCas.

In another subject I have been emailing back in forth with an Agon member that has a line 1 preamp. The topic was which tube spots were the most important in the Line one. He emailed "Sonic Frontiers" and they told him the second row LV2--V2 would yield the greatest sound difference. I was confused to say the least. I even changed the positions of the CCas and the PQs to have a listen. Needless to say I did not care for what I was hearing. In our emails I asked him to email Chris Johnson at Parts Connexion about the tube positioning. I mean who would better know than the designer. He emailed me back, Chris said the back row first then the second row then the front row. That made sense to me, that explained the difference I heard when I switch the tubes around. I asked him if he would post the great info he got from Chris Johnson, I hope when he gets the time he will. Bill, a fellow Agon member is using a pair of early 60s 7308 Telefunken in the back row. Might have to try that.

My tube placement now in the Line one,

LV1..V1... Siemens 60s NOS CCa 6922 gold pin tubes.

LV2..V2...Amperex 60s NOS PQ 6922 USA gold pin org label.

LV3..V3...Amperex 60s NOS PQ 6922 USA gold pin org label.

My system,

Arcam Alpha 9 CDp
AudioQuest power cord
AudioQuest Diamond X2 ICs

AR ES-1 TT, Rega RB300 arm, Clear Audio Aurum Beta Mk 2 cart
Grado PH-1 phono preamp.
AudioQuest Lapis X2 ICs

Sonic Frontiers Line 1 preamp
AudioQuest Diamond X2 ICs
Audio Research VT 50 power amp
AudioQuest Sterling 3 ...8' pair speaker cables
ProAc Studio 200 loudspeakers

3 dedicated circuits with hosp grade 20 amp levington duplex recepts, on the same phase in the panel.

Well here I am again. I bought me a matched pair of new NOS Early 60s Amperex 7308 PQ USA tubes. The first pair I received early this week. Turns out after just a few hours of time on them, one of the tubes became noisy, Microphonic. I bought them from Mike Miller, "Fat_Cat", here on Agon. I emailed Mike about my problem and Mike immediatley sent me another new pair, which I received today, {Saturday 3/26/05}. That is what I call a quick turn around. He said return the other pair when I got the time. I highly recommend Mike if you are looking to buy tubes with no worry.

I did get a chance to experiment with the Herbie's Hal O tube dampers on the microphonic tube. I found the Hal O helped control the noise best at just slightly above the top third of the tube. And also where the pads rested against the tube would make a difference. Even the tightness of the Hal O against the tube made a difference. Tighter was better.

The sound, how do they compare to the Siemens cca, I will have to report back later after I get about 50 hours on them.

Jim

Hi Jim, Lawrence here, the guys who sent you email regarding which pair of 6922 in Line 1 affected the sound most. As I mentioned to you I have both old Siemens CCa and Amperex 7308 PQ (white label). I been plucking in and out on both type tubes on both my Line 1 and Power 2. At the end of the day, I prefer Amperex 7308 PQ over Siemens CCa. Amperex sounded more full body and a touch of warmness as compared to Siemens CCa. Siemens sound clean, accurate, airy high and better control of bass but overall sound is kind of lean as compared to Amperex full body sound. Hard to put them in word, anyway, I prefer Amperex over Siemens CCa in my system. I let the Siemens CCaa sitting in SFCD-1 at the end of day. And last but not least, the white label certainly sound better than the orange label. Will continue with my experiments and post my opinions if there is new findings.
Lawrence

Lawrence, I like both the Siemens CCa and the Amperex PQ USA white label 7308 tubes. Both have their own sonic character. I have been switching them back and forth for weeks it seems. I do like the rich warm sound of the CCa on vocals. It is a tough call for me to say which sounds better. I do agree the orange label USA PQ 6922 is no match for the early white label USA PQ 7308 tubes. I wasted my money on that one.
What are you using for tube dampers. especially in the back row, LV1-V1?

I read your recent post, why are you thinking about a SS power amp? If you want a more SS sound from your power amp you might want to try electro-harmonix tubes. Email Chris Johnson at Parts Connexion see what he says...

So for now I have the CCa in the back row LV1-V1. The PQ 7308 in LV2-V2. and the orange label PQ in LV3-V3.

I am now looking for a matched pair of Telefunken E188CC early 60s. I want to try them in the preamp next.

Jim

My quest for the Telefunken E188CC, I am not having much luck. Them puppies are expensive! I have found a new matched pair of E88CC 6922 gold pin diamond bottom late 60s. Question, are Telefunken tubes like the Siemens and Amperex tubes where the early 60 tubes sound better than the later 60 tubes? I am hesitant toward buying them without knowing... I made that mistake on the orange label Amperex PQ 6922 tubes.

Jim