[gyrodec]

I just wiki'd the "whore" (I can now say that, as that was her charater). To use a wondeful old English phrase - "I wouldn't kick her out of bed for eating a packet of chips". (My wife, of course, would)

 

[ericj]

Quote:

Originally Posted by jinp6301 /img/forum/go_quote.gif I have both the CKK and the m^3 and I would suggest either based on your budget. The m^3 is a step above the CKK but for the CKK price, I think it performs great, especially with senns

I disagree somewhat. They are just very different amps.

I find my M^3 to excel at clarity and speed. It's a very transparent amp, but can tend toward sounding sterile. Mine currently has opa627/637 combo, but in the past I've had the ad8610, ad845, ad843, opa606, opa604, etc.

The CK2III on the other hand is more musical and fluid.

Also, the CK2III gives you the option of using just about any bipolar power transistor pair on the output, where the M^3 only works with the particular IRF parts it was designed to use.

 

[CountChoculaBot]

Are the M3, PPAV2, or CKKIII high current amps for use with low impedence cans? I'm looking for a suitable amp for a Denon D2000 (25ohm impedence-ish), and apparently a high current amp is what I'll need. I read the CKKIII is a high current amp, are the other two high current as well?

 

[gyrodec]

Yes, they are all quite robust and a match for almost any amp in terms of current (B22 and a few other special cases excluded).

 

[Gautama]

Quote:

Originally Posted by m3_arun /img/forum/go_quote.gif I have a SE CKKIII and its awesome with my HD580 with 650 cable and 600 grills. The only comparison I have is the builtin headamp of the EMU 0404 USB, but the CKKIII is a huge step above that. I can't really imagine a different (single ended) headphone amp giving a really large performance jump above the CKKIII. I think you should go fully differential/balanced to get the most sound quality, that's probably what my next upgrade will be. I don't really get how someone would set up a balanced CKKIII, because it already has an active ground?

Populate another board, send left and left inverse DAC outputs to one board and right and right inverse to another. Just wire the ground to the case or anywhere, it doesn't matter. The normal signal and the inverse will cancel out negating the need for ground.

 

[tomb]

Quote:

Originally Posted by gyrodec /img/forum/go_quote.gif Yes, they are all quite robust and a match for almost any amp in terms of current (B22 and a few other special cases excluded).

Actually, the M3 far exceeds the others in Class A bias current. The M3 runs a minimum of 80ma bias through the output MOSFETs, whereas the PPA or the CKKIII are normally set for about 30ma. I think most people are closer to 100ma with their M3's, though. The MAX runs about 50ma for BJT's, but the MOSFET version runs the same as the M3 with the same size sinks. It think the B22 (160ma) may outbias them all, though.

Does that make a difference? I think so with the right headphone. Sennheiser's will have all the current they want at 30ma - buffers set higher than that will actually run cooler than they do at idle with no load. However, headphones at about 50 ohms or below will tend to draw more current and load the buffer with more heat than just the bias alone. IOW, you could probably dial it up from 30-50ma. That's a very generalized description - mostly for Grados, HD25's or KSC75's, but it seems to hold true by my observation.

 

[Gautama]

Is there a negative effect if you have a lot of current and a high impedance phone? As in, using all the current and less voltage, or does it only take what it needs and the voltage stays the same?

 

[CountChoculaBot]

Wow, thanks for the info Tomb. Just what I was looking for, with specific numbers no less

 

[jinp6301]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif I disagree somewhat. They are just very different amps. I find my M^3 to excel at clarity and speed. It's a very transparent amp, but can tend toward sounding sterile. Mine currently has opa627/637 combo, but in the past I've had the ad8610, ad845, ad843, opa606, opa604, etc. The CK2III on the other hand is more musical and fluid. Also, the CK2III gives you the option of using just about any bipolar power transistor pair on the output, where the M^3 only works with the particular IRF parts it was designed to use.

really? I have the opposite experiance. I feel that the CKK is more neutral and less musical then the M^3, while I feel the M^3 is more fun to listen to

 

[amb]

Quote:

Originally Posted by Gautama /img/forum/go_quote.gif Is there a negative effect if you have a lot of current and a high impedance phone? As in, using all the current and less voltage, or does it only take what it needs and the voltage stays the same?

No negative effect on sound. The load will only draw what it needs. Biasing MOSFETs deep into class A has the benefit of operating the devices within their most linear region of their transfer characteristics, reducing distortion. The only drawback is increased idle power consumption and heat dissipation.

 

[fierce_freak]

I'm still thinking about just using a jisbos "amp" for the office, but I'll most likely use HD650's there. I know the jisbos page says that it probably isn't a good idea with high impedance 'phones (no voltage gain stage). This probably isn't a proper test for some technical reason I'm ignorant to (probably because voltage doesn't actually change in this test), but I've tried setting my source at -14dB hooked to my unbalanced b22 with a gain of 5 (gain of 14dB), and the headphones can still go way louder than I'd ever listen.

 

[gyrodec]

ff

Please build a JISBOS for the office. You have so much experience with all the different amps, and are a known good reference, so you input would be very, very useful for me. If you like it with 650s, I'm sure I'd like it with my 600s. (I'm thinking of a pro DAC, so I would have plenty of gain.)