Psvane T Mark II KT88 Question / M-125 Mono Blocks

Will probably install the Psvanes tomorrow mourning and let them run all day for a burn in. Need to try them any way incase of failure and need to return them or something.
 
I have a very similar Techincs deck setup next to my bench. It had sat for years unused and works like a champ. Original belts and everything.
 
@Vangoat , instead of using your marantz receiver preamp section to drive the tube amps, you should get much better sound if you save up and buy one of hte zero zone Marantz 7 clones. Great sounding tube pre for the money.
With regards to your PSVANE 88s, have used them before. They are good sounding tubes, but do not do well if the B+ is up near the design limit for the 6550/KT88.
 
Thanks everyone! Not sure what B+ is, I'm still new at this and learning. In the spec sheet for the M-125 mono, it says B+ on driver board > 380 - 420 volts DC. What ever that means, and are my Psvanes ok with that?
 
They should be ok. How long they will last compared to the Gold Lions?, who knows.
 
Thank you. No sense worrying about it I guess, just play and enjoy. I Installed them this mourning. Turned bias down, let them warm up for about an hour, biased them, let them sit for a few hours. Now playing a little Rush Hemispheres at low level for now. Sounds great.
 
Update, They do seem to have a slight hum. Will let them run the rest of the day with no signal going through. Heading for the trout stream tomorrow, will let you know in a few days how they are. Thanks guys!
 
Update, They do seem to have a slight hum. Will let them run the rest of the day with no signal going through. Heading for the trout stream tomorrow, will let you know in a few days how they are. Thanks guys!

I've had brand new tubes that were noisy to begin with, I recall a set of KT120 in particular, then after a few hours they quieted right down. Getters need time to do their job. I'm listening to Johnny Lang Live in Montreux DVD that just arrived today, highly recommend if liking blues. Good luck fishing!
 
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Thanks everyone! Not sure what B+ is, I'm still new at this and learning. In the spec sheet for the M-125 mono, it says B+ on driver board > 380 - 420 volts DC. What ever that means, and are my Psvanes ok with that?

yes, they should be fine with that. Some amps run up at 560 to 580 VDC, a bit too high for Chinese tubes.
 
I'm Back! Well here's my dilemma. I have about 15 hours of burn in time on the Psvanes. I can still hear a Hum from across the room. The Set that measures 45 seem to be a little louder than the 55 set. Tried rotating the two 12au7's, tried a used set of 12au7's, no change. The Hum is the same wether the stereo is turned on or off, volume does not affect the hum. Checked for ground loop, unplugged every thing except the amps, also tried to simulate a cheater plug by wrapping electrical tape around the ground lug on the AC plug, no change. Reinstalled a set of Gold Lions in one amp, no hum unless you put your'e ear up to the speaker, the other Psvanes can still be heard across the room. Don't think any amount of burn in time would help them. Any suggestions? should I continue to run them and see what happens or should I contact the manufacturer and return them. Thanks!
 
Didn't think I would have to, the amps are basically new and there is no problem with the Gold Lion's, they are quiet.
 
I will clean the pins and try again later, right now I have the Gold Lion's back in, NO HUM!!.
Besides the annoying hum when no music playing, the Psvanes sounded very good, a little bright but I'm sure would settle in in time.
 
Nice setup - very cool. I built my M125s back in 2011 - I had hum the entire time and devices to "lift it" (HumX) - mine now are in the process of a rebuild (thread here) and the new rebuilt one is very silent - in the 30's dB reading at rest up to the speaker dust cover - no ground lift - no HumX - and using a bucking transformer to get my voltage down to 116V.

Also - I only run two output tubes - I'll never go back to four in this day and age. I bias the two at just under .500 volt.

When I investigated a hum issue I had recently - after the rebuild (60's dB) - it was due to a bad KT88 - gold lion that I don't like and will hopefully never buy again. I figured it out by running only two output tubes and moving them around - first front sockets then back - at first I thought - it's the front sockets!!! - but I was wrong - it was the tube all along - with that bad tube gone - my hum dropped.

So try only two output tubes - rotate the tubes and see if it goes away.

Great having two amps as you can move tubes across the amps to find bad tubes.

Best of luck!
 
Ok, I'll try that and see what happens. Have company right now, will have to wait until tomorrow. Thanks everyone1
 
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