SET amp owners thread

Very cool, Brad! Congratulations!
THX Ron! Tried it out the other day for the first time...balanced it by ear but was sounding very good. Need to get the measurements on it to confirm the frequency response is reasonably flat.
 
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@morricab What amps are those monoblocks?
 
@morricab What amps are those monoblocks?
Those are Ladyday LD+ WE91 monos. They are derived from the famous WE91s but updated by Thorsten Loesch to have a wider bandwidth. They are the top version with very good Silk output transformers. Nice sounding and even pretty quiet on the 110db/watt horns.
 
@christoph,

Did you find the time to look at the manual for the 350?
Don't want to pressure you

Grüße, Remco
Hi Remco

Sorry, I haven't found the time to go into the attic and play Tetris with all the boxes up there :oops:

But I found a picture on the net that is explicit:
4-8 ohm setting.JPG

I hope this pic with the text is self-explanatory...

Please try anyways, which setting sounds better to you, no matter what your speakers "demand" :cool:
You can't destroy anything ;)
 
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Thanx Christoph!!!

This is exactly how it is in my amp atm.
So I will put the screws in the middle !!

As we all know, you have little to do on the easter-days, so you will find the manual in the attic :cool::D Or I come over and help you o_O:eek:

One other thing:
I had a problem with my KR Audio 350. After 3 hours of use, the amp did go in protection (green power led went red blinking) I had to switch off the amp, wait for 30 seconds, than the amp worked for 30 minutes, then the same.
I contacted the seller, in Aachen Germany (he gave 90 days retour option and 1 year of warranty!) and he helped me out from the first second. My amp was not used for more than one year.
He gave me a contact of a technician. I just needed to look at the bias, which I did. The protection window is quite small.
If someone is interested, I can post how to do it here, as even the technician did't know it exactly. As I have build some tube-amps, so I could find it myself.
The Anode Voltage is 915V, which was my first encounter with such high voltages, so I even was very careful.
After readjusting the bias, everthing was fine!

I even noticed there is a phono amp build in the amp :eek:
This is what the 350 Purity looks like from the inside:

2021-03-21 12.27.02-2.jpg
 
Thanx Christoph!!!

This is exactly how it is in my amp atm.
So I will put the screws in the middle !!

As we all know, you have little to do on the easter-days, so you will find the manual in the attic :cool::D Or I come over and help you o_O:eek:

One other thing:
I had a problem with my KR Audio 350. After 3 hours of use, the amp did go in protection (green power led went red blinking) I had to switch off the amp, wait for 30 seconds, than the amp worked for 30 minutes, then the same.
I contacted the seller, in Aachen Germany (he gave 90 days retour option and 1 year of warranty!) and he helped me out from the first second. My amp was not used for more than one year.
He gave me a contact of a technician. I just needed to look at the bias, which I did. The protection window is quite small.
If someone is interested, I can post how to do it here, as even the technician did't know it exactly. As I have build some tube-amps, so I could find it myself.
The Anode Voltage is 915V, which was my first encounter with such high voltages, so I even was very careful.
After readjusting the bias, everthing was fine!

I even noticed there is a phono amp build in the amp :eek:
This is what the 350 Purity looks like from the inside:

View attachment 76276
Just keep the now not needed anymore screws where you can find them again ;)
I would be interested in a how-to for the bias, please :D
 
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I wish all the tube amp mfg would put the bias points that is easy and safe to access. IMHO opening the amp up for biasing is just asking for trouble.
Thats right! I think this is realy a problem. Even for me it means a lot of work, just to check it.

Does anyone here know if Japan Kondo Audionote amplifiers have auto bias?
As far as I'm aware all are "autobias" .
Actually its just a resistor on the kathode of the tube, over which the voltage is generated. The other way, there is a seperate PSU for the bias.
The sound different, both have their advantages (don't ask, I've forgotten)
 
Just keep the now not needed anymore screws where you can find them again ;)
I would be interested in a how-to for the bias, please :D
2021-03-21 12.28.19 Kreise.jpg

FIRST: BE VERY VERY CAREFUL!!!!! High Voltages inside!!

Turn the KR Audio up side down. I took some books, as the T100 tubes are bigger than the transformer cases. Don't let the amp rest on the tube(towers)
Open the coverplate. When you power on the amp, make sure that the speakers are connected. Volume completely down.
Hook the voltage meter on ground (Black cable) and on Con 2 in the red circle. When the tubes are cold you will measure 1,3V - 1,5V which will slowely go down. After around 10 minutes adjust the pot in the yellow circle to 1,1V. Don't overdo it, but it can take some turns as the pot is a 10 turns one. Repeat on Con 10 and the pot besides it.
Recheck after 20 minutes.
The negative bias PSU voltage ist -199V (violet circle)

If the protection is on all the time, you cannot adjust as the amp doesn't have bias then.
If that is the case, you can disable the protection for this short (!) time to get to the values needed. This is done when pulling LM339 in the black circle:
2021-03-21 12.28.06 Kreis.jpg
Put it back when you adjusted the bias.

Here is the T100 tube socket :
2021-03-21 12.27.02 T100 Tube socket .jpg
The drilled red/black cables are the 5V filament voltage. You will measure 6,1V and 1,1V here, referenced to ground.

Remco
 
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Love those Vikings, I really want to hear a pair sometime, very intriguing. Enjoy and tell us all about the Vikings.
 
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Love those Vikings, I really want to hear a pair sometime, very intriguing. Enjoy and tell us all about the Vikings.


They are great speakers imo. I showed my SurgeX and cables with them and Audio Tekne at RMAF some years ago, we had the new AT 211 PP tube amps, they were really impressive! If you read about Viking speaker design on their website, they are unconventional in some ways but the result is excellent. The designer, David, sees speakers as functioning similar to instruments and makes sure his speakers sound good. I think he has an innate sense of what works psychoacoustically and his designs reflect that. Any speaker is going to have certain characteristics, Viking will have a pleasant sounding character that enhances the recording without getting in the way. I think the approach is similar to Harbeth and others that have a pleasant sound characteristic but still have good resolution and are capable of providing an immersive listening experience. Maybe not clear and neutral like YG, for example, but they are speakers that offer a top notch experience.

I almost got to hear the Gottenburg, which uses the 31" Fostex woofer and an enormous bronze horn, but the room at RMAF wasn't large enough. :( I think we had the Berlin monitors instead, which were a much better fit for the small hotel room, lol.

 
One of my clients uses the Berlin's with Shindo and Allnic phono and I would say the results are very nice
 
Btw has anyone here heard the 31" fostex woofers? Super curious if they are 'all that'. In general even 21" don't see much action in home or pro situations...
 
David is working on Gotenbergs right now. I hope I get to hear them.
 
Hi all.

I will share some pictures I got from Silvio Pereira, CEO of Audiopax.
He just released the new M88 Reference SET. The Reference is now the top of the Classic line. M88 is an awarded amp from Audiopax, 30W pure class A1.
the Reference got new power supplies, and it is impressive the result.

it is now playing on Audio Reference (UK) with Avantgarde Trio Classic XD.
Anyone in London that is curious about that so many times best of show combination (Audiopax + Avantgarde) I think Martin from AR would be glad to show how nice it is playing.

31AC4ACB-B45B-43F5-82AA-FBBABA9A9F31.jpeg

261BD977-E2E6-4BC1-BE35-FEA54F5D0A81.jpeg

B1F6B80D-9F12-40C5-88CE-39C1B079E7B0.jpeg
 
Gorgeous. I'm just waiting my turn to demo these with my Audiopax Model 5 and big Tannoys.

Tannoys and single ended are not normaly an ideal combination but we'll see ... very much looking forward to it.
 

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