Tubes that affect phono stage-- PV8
-
lectrolink
- Regular
- Posts: 6
- Joined: Sun May 21, 2017 9:19 pm
Tubes that affect phono stage-- PV8
Hi, suddenly getting noise and crackling out of the right channel, ONLY on phono input. I have the original owner's manual, and while it shows tube positions (V1 & V2- 12AX7; V3 & V5- 5751; V4 & V6- 5965), it has no indication which ones affect the phono stage. Does anyone know which tube may affect right channel phono? If not, guess I'll have to buy one of each tube and do the substitution method.
-
AnotherJohnson
- Ultimate
- Posts: 5219
- Joined: Sun Apr 26, 2020 12:29 pm
- Location: Tennessee
Re: Tubes that affect phono stage-- PV8
It’s probably one of the 12AX7s.
IIRC, V1-V4 are the phono stage.
Roberto undoubtedly knows for sure.
FWIW, my advice would be to just replace them all.
Either they’re all about the same number of hours, or their a hodge podge of different hours.
Put them all back on equal footing and, unless it needs caps too, you should be rewarded.
The PV8 was a great preamp. I had one for several years, eventually recapping it with the Teflon upgrade. Well worth it if you plan on keeping it.
IIRC, V1-V4 are the phono stage.
Roberto undoubtedly knows for sure.
FWIW, my advice would be to just replace them all.
Either they’re all about the same number of hours, or their a hodge podge of different hours.
Put them all back on equal footing and, unless it needs caps too, you should be rewarded.
The PV8 was a great preamp. I had one for several years, eventually recapping it with the Teflon upgrade. Well worth it if you plan on keeping it.
It’s just stuff. I like mine. I hope you like yours. I probably like yours too.
Re: Tubes that affect phono stage-- PV8
Agree with everything AJ says. To do some preliminary troubleshooting and to rule out a tube issue, swap the identical tubes one set at a time and if the aberration changes (channel or quality), you have identified the tube (or at least narrowed it down to two).
-admin
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Re: Tubes that affect phono stage-- PV8
Hola Chicos,
V1, V2, V3 and V4 are the phono preamp. If you have the noise only when phono is selected, then one of these tubes are the culprit of the odd noise. All these tubes are double triodes. So, you have to change one by one. Turn off the preamp, and pull out and insert it again in the same position. Some times, you might have a dirty connection between the base and the tube making this odd noise. When you pull out an tube, the base acts as a cleaner of the pins. Do this two or three times for each tube.
If you still have noise, then one by one you must replace the tubes. This method will find the noisy tube. As an example, you replaced the V4, then have a listen. If the noise persists, then put back the first V4 and now replace the V3...is the noise is gone, then that's the bad one. You can replace all them four too, of course at the same time.
Happy listening!
V1, V2, V3 and V4 are the phono preamp. If you have the noise only when phono is selected, then one of these tubes are the culprit of the odd noise. All these tubes are double triodes. So, you have to change one by one. Turn off the preamp, and pull out and insert it again in the same position. Some times, you might have a dirty connection between the base and the tube making this odd noise. When you pull out an tube, the base acts as a cleaner of the pins. Do this two or three times for each tube.
If you still have noise, then one by one you must replace the tubes. This method will find the noisy tube. As an example, you replaced the V4, then have a listen. If the noise persists, then put back the first V4 and now replace the V3...is the noise is gone, then that's the bad one. You can replace all them four too, of course at the same time.
Happy listening!
ML CLX BF-210 Stage X Motion 4. CJ 120SE amp ET7V2 pre, Holo May Kte Dac. Mac Pro. Power Cond. BPT Signature+ 3.5, Gaia II Feet. USB Lush^V3. Nordost SPM IC and Spk. Shun Mook, BCanto CD2 CD3. Linn LP-12/Unitrack tonearm/Denon DL103R MC.