[Zoide]

So, this sounds like a tabloid headline, but I'm a Dr. Xin fanboy after all.

I think his new line of IV amps (4 channels!) (http://fixup.net/talk/topic.asp?TOPIC_ID=1759) should get waaay more attention.

I'd thought he had merely miniaturized a currently existing amp architecture, but apparently it's a whole new concept in amp design. He's even considering publishing a paper about it!

Quote:

The latest 4-channel is so far the perfect amplification circuit. It is not rocket sciense, but the key part is as creative if not more. During the last 4 years I've done thorough research on portable amps and I have not found any documentation about the key idea of 4-channel. The idea, not just a simple combination of 4 channels, was inspired by Goto from his very creative thoughts and it was based on some very good published technical articles. All those articles are only one but big step away. One of those days I might publish a paper about it. There is no hype here, but I cannot give the details for now. All I can say is: the latest 4-channel technology is totally different than any currently-known circuit, including PPA, M-cube etc. It is so far the only circuit that has no known issues. I'm very happy that, after 4 years, I finally got all the issues solved. All credits go to Goto. I worked very hard, but without his hard and creative thinking and persistence, I could never achieve that. Also, if without all you supportive guys like Acr, I would never have gone this far. I did not let you down. The 4-channel technology, so is the best sound, belongs to you.

(http://fixup.net/talk/topic.asp?TOPI...59&whichpage=8)

Here are the latest RMAA benchmarks:

32 OHM load (Grado SR-60): http://www.fixup.net/products/iv/macroivgrado.htm

120 OHM load: http://www.fixup.net/products/iv/macroiv.htm

300 OHM load (Sennheiser HD-580): http://www.fixup.net/products/iv/macroivhd580.htm

I haven't received mine yet, and I bet most people who have ordered it haven't either. It turns out part of the reason is that the amps were announced before Dr. Xin was really ready, since somehow the info leaked out:

Quote:

I was not going to announce it that soon, but it was leaked out and email was burying me.

(http://fixup.net/talk/topic.asp?TOPI...33&whichpage=2)

I guess we should cut him some slack for that, and just hold on tight while we wait.

In the meantime, what do you guys think about the amp, from a design standpoint, etc.? How would you expect it to compare to the big boys? Or if someone has already got one (I think marroyo has?), even better...

OK, enough from me for now

 

[Azure]

None of the graphs display for me on those benchmarks

 

[Zoide]

Apparently it's a problem with how RMAA generates .png's. (http://forum.rightmark.org/topic.cgi?id=4:818)

Hopefully Dr. Xin will convert them to .jpg's. For now, they do display in Internet Explorer.

Quote:

Originally Posted by Azure None of the graphs display for me on those benchmarks

 

[mrarroyo]

I wish I had a Supermacro IV

. First I have to sell my AE-1 (for sale in the amp section). Then I have to sell my Supermacro III Version 6 and I just can't.

The SMIII Version 6 sounds so good with the OPA2134 and Hi-C Buffers!

Right now it is driving my Senn HD600 beautifully.

But I will order the SM4 soon.

 

[kiwirugby]

I have had my SM IV for about three weeks now. I can't address your question about what I think of it from a design standpoint, but I can tell you it is configured thus: OPA627, 1xBuf634 in HiC mode (I have the vesrion with the four swtiches). This may mean more others than me, so I offer it as an example of design.

My rig is this: Red Wine iModded 60gb iPod photo --> Wyvern AG16 mini-mini --> SM IV --> AKG DJ81 or Mooon Audio Blue Dragon re-cabled KSC75 (the impedance switch works well with the 75s). I listen to mostly classical and jazz.

It is hard for me to really sort out what does what to the quality of sound, but with the addition of the SM IV there is more clarity, bigger soundstage, excellent instrument separation and good balance across the frequency spectrum.

I hope I am done with this for a while, but knowing Xin....

 

[warrior05]

Quote:

Originally Posted by kiwirugby My rig is this: Red Wine iModded 60gb iPod photo --> Wyvern AG16 mini-mini --> SM IV --> AKG DJ81 or Mooon Audio Blue Dragon re-cabled KSC75 (the impedance switch works well with the 75s). I listen to mostly classical and jazz.

i believe it is time to upgrade your headphones because you sure have the source to justify it!

 

[Oliver :)]

Quote:

Originally Posted by mrarroyo Then I have to sell my Supermacro III Version 6 and I just can't.

Why not have Xin upgrade it once he makes up the price for that?

 

[mrarroyo]

Quote:

Originally Posted by Oliver Why not have Xin upgrade it once he makes up the price for that?

That is a posibility, depends on how much for the upgrade. If he asks $200 for the upgrade I end up paying $550 for the amp. I should be able to sell the Supermacro III Version 6 for $250 to $275. Thus making the price of the SM4 $450.

 

[Andrea]

But wasn't it Xin himself who said that 4 signifies "death" in China?

Btw, what exactly does the 4th channel do?

 

[fierce_freak]

4 does signify death in china (i also remember reading something about a passive 5th channel being added to the IV)
^ and this is my 666th post o_O

From what I understand the four channels are there to make it work like a pre-amp/power-amp combo. I think it keeps things seperate for the op-amp stage and the buffering stage.

 

[Filburt]

Looks like it's basically a separate ground splitter for each channel (instead of a common splitter like on '3 channel' designs). I can imagine this being sonically beneficial, although ideally one would have single op-amps in each 'channel'.

 

[kiwirugby]

Warrior,

The rig I described was my transportable. I have the AKG501s and DT880s in the arsenal also. Both work wonderfully with the set-up.

 

[digitalcat]

I just got the new supermacro IV with default configuration today. So far I've tried it with AKG K501, Senn. HD600, ER-4p and Ksc-35. This is the third Xin amp I've owned, the previous two being a supermini V6 and a supermini III. IMHO the supermacro IV is the only one in the three that drives K501 with absolute authority, as well as if not better than my maxed out PPA with diamond buffer. With my old supermini III, I've always felt that K501 has a slight coarseness in the high, not so much that bothers me in short listening, but it does make long listening less enjoyable. With supermacro, the high is silky smooth. I could listen it for hours without any listening fatigue. The soundstage is greatly improved, almost as wide as the PPA, and the imaging is perhaps even better than the PPA-I could place the instruments and voice better with the supermacro; with PPA, it's still excellent, but the positioning seems to be a little blurred when compared to the Supermacro.

More impressions coming later, have to get some sleep now,

 

[ODG]

Did you get the default 2134 or 275? I heard the 2134 is richer, fuller, while the 275 has more soundstage.

 

[Skylab]

I am SOOO tempted by the SuperMacro4, but my SuperMacro 3 V6 is less than a year old, so I'm having a hard time coughing up the dough. But it is awfully tempting!