[Stoney]

Can anyone compare for me the two Singlepower amps and the Mapletree amps?

Also, the Singlepowers are said to be single-ended triode. But, they have two output tubes. Does this mean the two tubes are in parallel? Or is it in fact a push-pull?

BTW, here are some relevant links, for relative newcomers to this subject (like me):

Vacuum Tube Valley Issue 11 about 6SN7
Head-Fi - Singlepower tube rolling thread
Head-Fi - Mapletree Ear+ or MG Head Otl MkII (tubey, good with Senn HD600)
Head-Fi - Singlepower Supra and MPX3 headphone amps
Head-Fi - What's bad about MPX3??
Head-Fi - Picture of inside MAD Ear+ Purist HD
Mapletree MAD tube Headphone amplifier review
Mapletree Audio Design Ear+ Amplifier (Tube) Review by Steve A at Audio Asylum
Head-Fi - Review: Mapletree Line 2m Preamp

 

[Carlos3]

Quote:

Originally posted by Stoney Also, the Singlepowers are said to be single-ended triode. But, they have two output tubes. Does this mean the two tubes are in parallel? Or is it in fact a push-pull?

Parallel.

 

[gbeard]

Originally by immtbiker

Quote:

I hope the same holds true for the Supra. I have 70 hours burn-in...but I am burning in the amp, a Cary 306/200 and a pair of Cardas Neutral Reference IC's all at the same time. Up until yesterday, the Bass was a little muddled, and the depth was a little shallow. Not sure if it's the amp though because Cary demands a 100 hour burn-in time in the manual. Only time will tell.

Immbiker,

Give that Cary plenty of break-in. If it is anything like the 303/200 it will keep improving a little at a time and then one day you'll notice it has gotten way better. I mean a HUGE difference. I think you will report back that you are very happy.

 

[Stoney]

Now that I'm more awake, it seems obvious that the output would be paralleled sections of a dual triode, one per channel. I'll just look at the interior photo to figure it out next time.... ;^)

Anyway, the virtues you folks are attributing to these amps certainly seem tempting. I'm not a big headphone fan, but a relatively out-of-the-head-sounding pair of 'phones like the HD600 or HD650 (one hopes) plus a seductive SET amp with vivid midrange... that sounds like what would please me if anything would.

 

[immtbiker]

gbeard...
Thanks for the advice...It is the most used appliance in my house right now, so it's maturity level should rise as time goes by.

 

[Dusty Chalk]

Quote:

Originally posted by Stoney Also, the Singlepowers are said to be single-ended triode. But, they have two output tubes. Does this mean the two tubes are in parallel? Or is it in fact a push-pull?

Stereo, I think (is that what you meant by "parallel"?).

 

[Tomcat]

Quote:

Originally posted by Stoney Now that I'm more awake, it seems obvious that the output would be paralleled sections of a dual triode, one per channel. I'll just look at the interior photo to figure it out next time.... ;^)

Stoney,

I am not so sure that your original question has been answered by anyone. I still don't know whether the double triode in each channel's output (and the 6SN7 is a double triode) is wired in parallel or in push-pull. Does anyone know for sure?

 

[Hirsch]

Quote:

Originally posted by Tomcat Stoney, I am not so sure that your original question has been answered by anyone. I still don't know whether the double triode in each channel's output (and the 6SN7 is a double triode) is wired in parallel or in push-pull. Does anyone know for sure?

The triodes are configured to operate single-ended, not push-pull.

 

[Tomcat]

Hirsch,

People have called the Earmax Pro single-ended, when, in fact, the double triodes in its output stage are in a shunt-regulated push-pull configuration. There is just one tube for each channel, yes, in that sense, it's single-ended, but the actual circuit is SRPP.

Some buzz words seem to be somewhat of a moving target and "single-ended" isn't always used with the exact same definitions by every designer and every company. When Mikhail said that his amp is single-ended, has he explicitly talked about "parallel single-ended" (PSE) or has he been refering to the fact that there is just one output tube per channel? So called "single-ended push-pull" or SEPP designs are quite frequent when it comes to OTL amps.

 

[Stoney]

I had not recognized any other meaning for "single ended" other than "half of a push-pull." Amplifiers are "single-ended" or not in their topology; the number of tubes is simply the number of tubes.

Referring to a single dual-triode tube wired in push-pull as "single ended" sounds to me as if a non-technical person mis-applied the term. But, maybe I'm behind the times regarding accepted usage. ;^)

According to Mikhail, today:

"We use two cathode followers in singe-ended mode. Both triodes are wired in phase."

He says he may write a mini-white paper about the confusion about termininology.

 

[Dusty Chalk]

Quote:

Originally posted by Stoney He says he may write a mini-white paper about the confusion about termininology.

That'd be nice, as you guys have completely lost me. I thought single-ended just meant not balanced.

 

[HighwayStar]

Quote:

Originally posted by Dusty Chalk I thought single-ended just meant not balanced.

That it does, when you're talking connections between components, RCAs vs. balanced. How you implement a tube into a circuit is another thing. I'm not up on it and won't attempt to explain it, but if anyone can, it's Mikhail. Though I've got a feeling Hirsch can as well

 

[Habib]

Ha, I just got my MPX3 and I started my own thread. Take that!

 

[Rob N]

My MPX3 has upgraded output caps,does anyone know what make Mikhail uses?

Also,what make of resistors does he use?

 

[immtbiker]

Quote:

My MPX3 has upgraded output caps,does anyone know what make Mikhail uses? Also,what make of resistors does he use?

2 x 3300uf Res. Capacitors (Mallory Computer Grade)

Metal Film Resistors (don't know make)