New SET mono amplifiers

Randy Myers

Randy Myers

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I decided to go full back to basic, music first in my system. With my recent trying and loving using my Dennis Had DHT pre-amplifier/headphone amplifier to be the controller in my system. I decided that back to basic, music first is what I like the most.

I just made a deal for some SET Class A, Triode mono block amps. These babies are powerful, for SET amps :)...

Here is the write ups:
Audio Mirror 45 Watt Parallel SET Tube Mono Power Amplifier
This pair of monoblocks features the optional transformer-coupled XLR balanced inputs as well as single-ended inputs.

45 watt per channel mono-blocks are based on 6C33C Russian power tube. These all triode amps are one of the most powerful single ended amps on the market. The input stage is based on 6SL7 tube and the driver stage is with 6SN7. At the output are two 6C33C tubes in parallel. The amp design is a result of years of research and experience. A lot of trials and errors and of course very critical listening. We listen to our amps. We believe that measuring can show you very little of how the amp sounds. We listen and compare. That's how we achieve superior sound. Mono-blocks are point-to-point wired. Silver is the metal we use to run the signal through. High quality camps and grain oriented lamination M6 for the output transformers. The amps are autobiased in a unique way. Thus the amps are capable of very low end and very well controlled. Tight, fast and very dynamic bass. Mids and highs are so clear, opened and transparent. No fatigue from listening at all. Very musical and lively sound is produced by implementing some own proprietary design circuits. Most of caps are eliminated using DC coupling between stages. Actually, there is only one cap in the signal path. Amps have overload and runaway protection. These are some details revealing the build quality of the amps. The 45 watt power is real. The amps clip above 60 watts. Dynamic power is over 100 watts. They can driver very hard-to-drive loads, inefficient speakers and even electrostatic speakers which are hungry for power.

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They are nice amps. I have had a pair of these. If you are into any tube rolling, the 6sn7 has more influence than the 6sl7. I ended up using an adapter and used an RCA 6F8G which gave it a HUGE & DEEP soundstage.
They are powerful for a SET but they would shut down in protection mode when driving my Maggie 1.7's in my moderate sized room.
But all in all a fun amp. Congrats on the purchase. Enjoy
 
Randy, very nice!
Also looking forward to your experience with them.
You've gone through different amp architectures.
I wonder what impression these will make on you (in the long term).
 
Thanks everyone. I have gone through considerable changes experimenting and re-learning this crazy hobby since jumping back in a few years ago.

Back in the day I ended up with basic function gear leaning towards musicality over all else. I guess my new journey is leading me back down the same path :)...
 
I believe people get too caught up in WPC numbers. I have had 300 WPC amplifiers, etc., but have always enjoyed lower power pure musical oriented amplifiers. I loved the First Watt amplifier, for example.

These guys, at 45 Watts are on the high end of these types of amplifiers. They should have no issue powering my KEF speakers!

Good luck with the Decware Zen if you decide to go that direction.
 
Steve wirh Decker just said something very interesting to me. I listen mostly at low to moderate low volumes. An amplifier likes to work. If I'm listening at low volume and I have a lot of power, my amp is basically idling and not opening up like it should. With my 96 DB speakers now I think I'm experiencing that. It really blooms when I turn it up loud. At low volumes it seems to be for a better word just idling.
 
Interesting view point. I would say the same with a pre-amp. A pre-amp, to perform it's best should be able to have the volume from 11:00 - 1:00 on the dial (or even slightly higher). I remember reading this in a manufacture's pre-amplifier manual, but I cannot remember who's it was.
 
It would seem if an amp likes to be "driven", that it had better have been designed with some headroom, power reserves for demand peaks.

In regard to preamps it would seem where your volume control should be depends on at what point distortion begins. I only owned one preamp that had a switch for high or low output gain. Most preamps, unless a low watt power amp, won't let you get to 11. Well, unless hard of hearing or sitting at the opposite end of a football field.

I'd have to read a white paper or have more of a consensus from amp designers before buying onto they need to be driven at the top end of ability.

May just be my interpreatation, I sense some kind of conspiracy theory that small watt amps somehow sound more "musical" than a large power amp. I suppose technically that's subjective, although a wild generalization. Either way, I'm not buying it.

I don't believe in too much power :)
 
The theory behind running the volume control up around the 10 oclock to 2 oclock for better sound comes from the older wire wound and carbon wiper pots. At the bottom end they were not very linear and did not necessarily track evenly between the channels. This improved as the middle section of the pot was reached. With today's improved potentiometers, stepped attenuators, voltage regulators ETC used as volume controls the basis of that old school of thought has been mostly eliminated.
 
By the way Randy, super envious of your new amp. It looks beautiful. I bet its going to be a crowning Jewel of tonal Elegance. I hope it's what makes your system shine.
 
They do look nice, will be interesting to hear what you think in a few months.
 
Thank you for the replies, suggestions, and inputs. I am super excited to listen to these. From the research I have done they sound like they will be right up my alley. I am planning on keeping the classic McIntosh. I can listen to it sometimes if in the mood, but also as an incredible show piece. It is closing in on 30 years old but looks and sounds like it just rolled out of the factory!

I have not decided yet on the T+A AMP8. I might sell it??? The KEF R400b sub I will be putting up for sale. It is part of the newly designed R series. I will also probably be selling the AQ Earth XLR cables. I just have to get some time to put together these ads.
 
Randy

If you look to replace the sub at some point look for one that can be connected both line and speaker level like the REL's or the Rythmik's.
 
Thanks Jack. That is what I was also thinking. At this time I do not believe I will miss the sub. When I had stand mounted speakers it was definitely required, but with the floor standing speakers, in my smallish loft library, it really is not needed. Been listening with just the R700s the past few days and I seem to get all the low end I need. I have noticed that the bass really comes into focus after the Had pre-amp has been on for about 20 minutes or so.
 
Handsome amps Randy. I tried a 845 based SET amp out of curiosity. It was around 25 watts per. I just couldn't find any advantage to keep it. I threw several sets of speakers and cords at it with no success. I went back to a much more powerful class AB setup.
 
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