Hello,
i have a preowned AI 3 convertetd with a M3A board and John Curl Boards. I like this Amps and the MC pre sound delicious. I bought it 1.5 years ago with a quad set of
6H23p tubes. As they become "hissy" (sounds like the wind blows through your speaker), i have changed them to a new quad EH6922 (gain switch is low).
After 25 hours of listening in 3 months I got the hissy stormy sound again in the left speaker. I unscrewed the topplate, the sound was good for 30 minutes, than the hiss (or like waves - volume is changing) on the left speaker was back.
Questions:
- If the tube will get burned out by the AI...will the hiss be permanent?
- 6922 EH not so stable as 6H23p?
- What is better for the tubes - switch to high or low gain?
- Should i replace the electrolytic caps?
- Is there a way to change the filament or anything to stop valve eating? (I read it in another thread but I would need a part list an exact guided way what to change from somebody who had done it)
Thanks for feedback.
Marcus
i have a preowned AI 3 convertetd with a M3A board and John Curl Boards. I like this Amps and the MC pre sound delicious. I bought it 1.5 years ago with a quad set of
6H23p tubes. As they become "hissy" (sounds like the wind blows through your speaker), i have changed them to a new quad EH6922 (gain switch is low).
After 25 hours of listening in 3 months I got the hissy stormy sound again in the left speaker. I unscrewed the topplate, the sound was good for 30 minutes, than the hiss (or like waves - volume is changing) on the left speaker was back.
Questions:
- If the tube will get burned out by the AI...will the hiss be permanent?
- 6922 EH not so stable as 6H23p?
- What is better for the tubes - switch to high or low gain?
- Should i replace the electrolytic caps?
- Is there a way to change the filament or anything to stop valve eating? (I read it in another thread but I would need a part list an exact guided way what to change from somebody who had done it)
Thanks for feedback.
Marcus
I own a 3a and it is hard on tubes. You really need to buy from them as this preamp will quickly bring out marginal tubes already close to the edge .
At this age it is a good idea to replace electrolytics but it most likely is not the problem
Spend the money and get tubes from AI
At this age it is a good idea to replace electrolytics but it most likely is not the problem
Spend the money and get tubes from AI
Hi Avwerk,
I was thinking that the default tubes are EH6922.
Audible Illusions Modulus 3A - Original Equipment Package
I was thinking that the default tubes are EH6922.
Audible Illusions Modulus 3A - Original Equipment Package
New Tube-Sockets?
What I found out so far, is that if I twist the tube from the channel which makes the noise, the is a loud crack and then it is quite. So no hiss.
Should I replace the Sockets or the pins due to bad contact to the tube?
What I found out so far, is that if I twist the tube from the channel which makes the noise, the is a loud crack and then it is quite. So no hiss.
Should I replace the Sockets or the pins due to bad contact to the tube?
I'm looking for a way to extend tube life in my Audible Illusions M3A. Seems some keep the power supply on 24/7/365 and others only send AC to the power supply when they are going to listen to music. Has anyone tried/or is only plugging in the power supply when they will listen to music. If so has it effected tube life?
Thanks
Thanks
I own an AI 2D.
I’ve owned it over a decade now.
When I first purchased it off someone on Audiogon the faceplate was damaged during shipping due to sub-par packing.
I sent it to AI in Florida. Art was nice enough to go through it for me and even replaced the faceplate with a piece from one of his personal preamps.
He put in a lightly used set of EH6922 that he had tested. Replaced the mute switch which was on the fritz (it is again). I asked about the caps…he said they were all fine.
I realized after getting it back that it sounded great for a while, but within 6 months not so much.
Read up on how hard the AI can be on tubes.
I purchased the matched set of EH6922 that a link was posted to.
I now cycle the entire system off with a Monster Power center that its all connected to about 15 minutes in advance. No more idling of the tubes in standby.
I won’t say I listen to the system every day, but I listen a few times for a couple hours weekly. It’s been a few years since I last replaced the tubes. Sound quality is still very good.
I don’t use the phono section anymore as I have a ZYX CPP-1 that I use for MC step up in front of a few different phono amps I’ve built. I never thought the 2D phono amp section was all that great.
The only time I experience some hiss or flutter is if I have the volume at high levels listening to concert/live recordings.
I’ve tested the preamp at the same level with digital sources…it’s silent. The noise is in the Phono amps.
I’m using the AI with a pair of Quicksilver Horn Monos that are driving Tannoy System 15 DMTii.
I’ve owned it over a decade now.
When I first purchased it off someone on Audiogon the faceplate was damaged during shipping due to sub-par packing.
I sent it to AI in Florida. Art was nice enough to go through it for me and even replaced the faceplate with a piece from one of his personal preamps.
He put in a lightly used set of EH6922 that he had tested. Replaced the mute switch which was on the fritz (it is again). I asked about the caps…he said they were all fine.
I realized after getting it back that it sounded great for a while, but within 6 months not so much.
Read up on how hard the AI can be on tubes.
I purchased the matched set of EH6922 that a link was posted to.
I now cycle the entire system off with a Monster Power center that its all connected to about 15 minutes in advance. No more idling of the tubes in standby.
I won’t say I listen to the system every day, but I listen a few times for a couple hours weekly. It’s been a few years since I last replaced the tubes. Sound quality is still very good.
I don’t use the phono section anymore as I have a ZYX CPP-1 that I use for MC step up in front of a few different phono amps I’ve built. I never thought the 2D phono amp section was all that great.
The only time I experience some hiss or flutter is if I have the volume at high levels listening to concert/live recordings.
I’ve tested the preamp at the same level with digital sources…it’s silent. The noise is in the Phono amps.
I’m using the AI with a pair of Quicksilver Horn Monos that are driving Tannoy System 15 DMTii.
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All my equipment is in a closet and all switches and controls are on front panels so I don't have to reach inside. I'm making a power switch for the power supply that will sit on top of the power supply so it will also be easily accessible.
I just purchased a AI M2A with a set of NOS Soviet 6922's couple of months ago. For about a 2 weeks I listen to it using different amps I had on hand to match it with. Finally settled with a Son of Ampzilla connected to it, sounds good. Now the muting switch (no sound output and the relay clicks as it would normally) seems to be "on the fritz". However, when it played I noticed no unusual hissing or hum. I didn't get the chance to listen to the phono section ( my turntable is loaded with a LOMC).
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You can unplug your pre, it's probably a good idea to do so as a safeguard from spikes on your mains. It's not going to save that much in tube life tho. Shoot me a message offline for more info.
W
Hi Marcus, Try cleaning the tube sockets and tube pins before discounting the tubes. The switch for gain isn't the issue relating to tube longevity.Hello,
i have a preowned AI 3 convertetd with a M3A board and John Curl Boards. I like this Amps and the MC pre sound delicious. I bought it 1.5 years ago with a quad set of
6H23p tubes. As they become "hissy" (sounds like the wind blows through your speaker), i have changed them to a new quad EH6922 (gain switch is low).
After 25 hours of listening in 3 months I got the hissy stormy sound again in the left speaker. I unscrewed the topplate, the sound was good for 30 minutes, than the hiss (or like waves - volume is changing) on the left speaker was back.
Questions:
- If the tube will get burned out by the AI...will the hiss be permanent?
- 6922 EH not so stable as 6H23p?
- What is better for the tubes - switch to high or low gain?
- Should i replace the electrolytic caps?
- Is there a way to change the filament or anything to stop valve eating? (I read it in another thread but I would need a part list an exact guided way what to change from somebody who had done it)
Thanks for feedback.
Marcus
Shoot me a message if you'd like further info.
Happy listening!
Wheezer
Hi, the EH are a good alternative to the Sovtek and 6H23p but the EH won't last as long in an unmodded AI.
The mute switch should not have gone bad, again. Try a can of compressed air into the switch via the straw which comes with the can. I've rarely replaced a mute switch in an AI. If you would like further info on the tubes and mute switch, etc, feel free to message me here.
Happy Listening!
I bought a pair of Philips pcc88 7DJ8 tubes for the line stage and the M3A is dead quiet and the sound is great. Hope they last and I'm only turning on the power supply about a 1/2 hour before I listen.
Yes, the 7dj8s are eerily quiet because the heater volt is 7.0 whereas the 6922 is 6.3. The AI in stock form runs the heaters around 5.7v. Not optimal emissions.
The plate voltage for the 7dj8 is the around the same as the 6922 90v. Your 7dj8s won't last. If you'd like more info, email me. wheezer1@comcast.net
The plate voltage for the 7dj8 is the around the same as the 6922 90v. Your 7dj8s won't last. If you'd like more info, email me. wheezer1@comcast.net
The sound with thes 7DJ8 tubes is better than ever. I made the outboard switch so it is very easy to turn off the power supply. I'll see how long they last.
I found the following a few months ago and Upscale audio seems to have a similar feeling about these tubes.
Original National PCC88 made by the Matsushita Corporation of Japan.
These have had rave reviews all over the Audio world as a replacement for the ECC88, E88CC and 6922 family of valves. The only difference is the PCC88 has 7 volt heater whereas the ECC88 & 6922 family of valves has a 6.3 volt heater. So the valves are totally interchangeable.
A problem that is widely reported on the internet that many people have had with American high end amplifiers such as Conrad-Johnson. These amplifiers run the heater voltages on the ECC88 6922 in excess of the 6.3 volts. This causes the valve to go noisy after around 200 hours use.
The PCC88 having a 7 volt heater in this application gives extended life and the same Audio performance. They are also cheaper than their 6.3 volt rated brothers.
So it is simple win all the way round.
The National Matsushita PCC88 is considered one of the best sounding low noise replacements for the ECC88, 6922, 6DJ8, E88CC family of valves.
The valve has excellent balance with excellent midrange depth and top end clarity.
Original National PCC88 made by the Matsushita Corporation of Japan.
These have had rave reviews all over the Audio world as a replacement for the ECC88, E88CC and 6922 family of valves. The only difference is the PCC88 has 7 volt heater whereas the ECC88 & 6922 family of valves has a 6.3 volt heater. So the valves are totally interchangeable.
A problem that is widely reported on the internet that many people have had with American high end amplifiers such as Conrad-Johnson. These amplifiers run the heater voltages on the ECC88 6922 in excess of the 6.3 volts. This causes the valve to go noisy after around 200 hours use.
The PCC88 having a 7 volt heater in this application gives extended life and the same Audio performance. They are also cheaper than their 6.3 volt rated brothers.
So it is simple win all the way round.
The National Matsushita PCC88 is considered one of the best sounding low noise replacements for the ECC88, 6922, 6DJ8, E88CC family of valves.
The valve has excellent balance with excellent midrange depth and top end clarity.
Yes, that makes sense if a mfg. runs the Vh in excess of 6.3V. In the case of AI, the Vh far lower around 5.7 or lower, which doesn't allow the tube to heat providing proper emissions. That said, they still have a max. Vp of around 90. Ai runs the Vp substantially higher than 90. The high Vp is what kills the tubes and not the Vh.
Seems you've got the right perspective on 7DJ8 tubes in the AI M3A. Kevin Deal at Upscale Audio does say he wouldn't use the masushita 7DJ8 in an Audblie Illusions M3a. So when these great sounding tubes get tired I will look for other tbues