Singlepower Square Wave w/ DAC internal pics

[kevin gilmore]

much better now.

http://gilmore.chem.northwestern.edu/dinglepower2.jpg

complementary sziklai pair with gain.

[kevin gilmore]

oops, forgot the 2000uf of output capacitors per channel

:D

output capacitors on a solid state amplifier

Reminds me of a dynaco Stereo 120

[luvdunhill]

much better now.

http://gilmore.chem.northwestern.edu/dinglepower2.jpg

complementary sziklai pair with gain.

I find the lack of Japanese parts disturbing

[n_maher]

Kevin,

If those 4x1000uF caps at the back are the output coupling caps that you're referencing am I correct in seeing that this thing has no local power supply capacitance?

[kevin gilmore]

you are absolutely correct... No local power supply caps...

pretty grim huh??

how do you like the adjustable bias by jumpering across

(or otherwise removing) one of the diodes...

all that space wasted when they could and should be

power supply caps, and then a simple opamp servo to

control the dc level.

Still hoping that one day i see something good from mikhail.

Same thing with ray...

Next time mikhail may do a solid state amplifier with an output

transformer. (very McIntosh like)

[n_maher]

you are absolutely correct... No local power supply caps...

pretty grim huh??

Sort of, especially considering that I was under the impression that this was the power supply.

Doesn't look like anything particularly special and I can't imagine it's got much reserve capacitance. And I'm with you, it's not like he's strapped for real estate in the chassis so why he'd do this is beyond me.

[kevin gilmore]

How much you wanna bet that the SS1 beast ($14k) is roughly

the same thing on the inside.

What a really mean joke to play on unsuspecting people.

[Asr]

Sort of, especially considering that I was under the impression that this was the power supply.

sqwv_psu_x1.jpg

Doesn't look like anything particularly special and I can't imagine it's got much reserve capacitance. And I'm with you, it's not like he's strapped for real estate in the chassis so why he'd do this is beyond me.

Here's a better pic of referenced power supply:

[kevin gilmore]

I wonder what he does with the +5 volts

[kevin gilmore]

updated schematic, same name same place.

I cannot find the words to accurately describe what i think

of the capacitor output section...

[luvdunhill]

updated schematic, same name same place.

I cannot find the words to accurately describe what i think

of the capacitor output section...

profitable?

[Augsburger]

Paradigm shift?

[luvdunhill]

perverted coupling?

[Hopstretch]

Mockery cease! Square Wave > Zana Deux. (Um, I think? It's somewhat convoluted.)

[dvse]

Given the stream of consciousness style, one has to seriously doubt authors' critical ability.

[Asr]

Mockery cease! Square Wave > Zana Deux. (Um, I think? It's somewhat convoluted.)

Are those meet impressions supposed to make sense?

And I myself question the listening ability of ole HeadphoneAddict there. At the Colorado 7/26/08 meet, he wanted to get my opinion of the WA GES prototype vs Stax SRM-1 MK2 using a Stax OII MKII and Stax Lambda and for a while there we were seriously trading headphones in like 3-5 second intervals. Like anything useful can be gathered from 3-5 seconds. If I'm supposed to provide actual impressions, especially between amps, in meet conditions, I need time to at least listen to an entire track and twice at that, not 3-5 seconds of it. (Though I did spend further listening time after he ended that crazy headphone-swapping session.)

He also states there the Square Wave XL is "8-channel". I doubt the Square Wave XL is even 4-channel given its size, the single-ended one only has just enough room for the stereo discrete circuits (and they're the same size!).

I'm also starting to question if Mikhail has actually made a Square Wave amp (non-DAC, w/ DAC, or XL version) since 2007, as the DAC version I have was also made in 2007, like the non-DAC one I had earlier. When I traded in at the aforementioned meet, I asked him if he recently changed the circuit and he said he did, and that the new one I had in my hands had it inside. But that seems to counter what I actually saw when I opened it to take pics, which identifies the board as "Rev A" from March 2007.

[kevin gilmore]

He also states there the Square Wave XL is "8-channel". I doubt the Square Wave XL is even 4-channel given its size, the single-ended one only has just enough room for the stereo discrete circuits (and they're the same size!).

Need picture of XL to confirm.

Here is my guess, the area taken up by the input switching and room for the

dac is gone, replaced by a total of 4 amplifier circuits. 2 of which have the

capacitor outputs. These are the + output of the balanced, and the output

for the unbalanced. The - outputs of the balanced don't really need output

caps. Since mikhail is absolutely so against any opamps, there is some cheesy

unity gain inverter made out of a pair of fets to drive the - output when in

unbalanced in/balanced out mode. Obviously there is no inverter necessary when

running in balanced in/balanced out mode.

I have figured out where mikhail got his output stage from and i have notified that

person.

[Asr]

Well I think we can all agree the Square Wave XL is not 8-channel at least. And it must be seriously crammed to pack in 4 discrete circuits in that small chassis...

Whoa, did Mikhail steal the design of the output stage?

[spritzer]

Whoa, did Mikhail steal the design of the output stage?

Aren't all the SP amps "borrowed"?

[Asr]

Aren't all the SP amps "borrowed"?

I would've hoped Mikhail was above that, but if that's the case...it lowers my opinion of him. But in any case I'm done with Mikhail and his amps, it's too much trouble dealing with him.

[spritzer]

I would've hoped Mikhail was above that, but if that's the case...it lowers my opinion of him. But in any case I'm done with Mikhail and his amps, it's too much trouble dealing with him.

The ES-1/2 is a Stax design from the 60's which he just swapped out the tubes and fitted a different PSU. The same goes for at least some of the dynamic amps but I haven't been following them. At least one of them though is identical to a Woo Audio unit so both are using the same 3rd party circuit.

[Dusty Chalk]

I have figured out where mikhail got his output stage from and i have notified that person.

Was it not a public domain design?

Aren't all the SP amps "borrowed"?

Practically all circuits already exist at this point, the trick with any amp manufacturer is to put your own flavor on it (without violating intellectual property rights, of course). Which is what I thought everyone -- including Mikhail -- does. Edited August 17, 2008 by Dusty Chalk

[n_maher]

Was it not a public domain design?

I'm guessing it was a published, not for commercial use type of thing.

Otherwise I can't believe that he had the gall to just rip that DAC out of a cheap soundcard and bolt it into his product. For all he'd done with the screwing around with customers orders, endless delays, and so on this is the one that disappoints me the most. I mean come on!

[guzziguy]

Otherwise I can't believe that he had the gall to just rip that DAC out of a cheap soundcard and bolt it into his product. For all he'd done with the screwing around with customers orders, endless delays, and so on this is the one that disappoints me the most. I mean come on!

At least it's the fast approach to adding a DAC.

[naamanf]

Otherwise I can't believe that he had the gall to just rip that DAC out of a cheap soundcard and bolt it into his product.

He could at least have used a good one. Even drawing up a simple board to use a PCM2707 would have been better.