[slowpogo]

I've built a PIMETA, and am really happy with it. But now I'm already thinking of the next thing to build.

I just noticed the Millet MAX project, and am sorry to have missed out on the group buy. But it got me wondering, which DIY headphone amps out there (well-supported ones) are considered especially high-end, competing to be "the best"?

Basically, I'm ready to build something more advanced, a reference-level amp. It would only be my second headphone amp, but I've done a substantial amount of other electronics work with guitar amps, so it would be more like my 5th or 6th project. Any suggestions of what to build next?

 

[MisterX]

Quote:

But it got me wondering, which DIY headphone amps out there (well-supported ones) are considered especially high-end, competing to be "the best"?

http://www.amb.org/audio/beta22/

 

[cotdt]

of course the balanced Beta22 would be the reference among DIY amps. it measures so very well.

Edit: someone beat me to it.

 

[vYu223]

Around how much would it cost to build a Beta 22? For future reference...

 

[cotdt]

Quote:

Originally Posted by vYu223 /img/forum/go_quote.gif Around how much would it cost to build a Beta 22? For future reference...

It depends. Some people spend $1000 on the CMoys, while others only spend $20. The 2-channel Beta22 with the cheapest parts and a wooden enclosure from free wood (you can find them near dumpsters) can be done under $300. You can easily spend $1600 or more for a maxxed out balanced Beta22 for speaker use. Some people spend over $1000 just for the volume pot, and use pure solid gold volume knobs. So your question is difficult to answer.

 

[Calroth]

You can get a fully balanced ß22 kit for US$438.50. A bit less than that if you "only" want a 3-channel active ground rather than fully balanced.

 

[philodox]

I would think that the reigning King based on owners and acclaim by well regarded members would be the Dynahi/Dynamight. The ß22 is the 'new' King, but looks to be fast overtaking the gilmore design.

 

[a1rocketpilot]

Is the Beta22 objectively better than the Dynahi, or is it a matter of user preference, based on sound signature?

Aditya

 

[thrice]

There aren't a lot of Beta 22 amps out there yet and they have not been compared to many of the older designs. Over time we will answer this question.

 

[philodox]

Quote:

Originally Posted by a1rocketpilot /img/forum/go_quote.gif Is the Beta22 objectively better than the Dynahi, or is it a matter of user preference, based on sound signature?

Right now it is FoTM, but as thrice says we will have more concrete impressions once more people get a chance to listen to the ß22.

 

[MisterX]

Quote:

Is the Beta22 objectively better than the Dynahi

Yes.

 

[cotdt]

I've compared the B22 to a dozen or so different amps, but too little time to write impressions. I also have mine balanced. I'm a big fan of both the Dynahi and the Beta22, but as usual I will give my honest opinion. The Beta22 is objectively better than the Dynahi, as it measures better in every category. The slew rate is much higher 200 V/us versus 70 V/us. Output impedance is also much lower than the Dynahi. No DC servo either, so it is a true DC amp and also a true discrete amp. The power supply can supply much more current than the Dynahi's but of course the Dynahi can use the same power supply for fairness. You'll need to do this for speaker use. Some of the coupling capacitor values for the Dynahi is less than optimal and you'll have to run simulations (or guess and check with different values) to find the optimal values. Whereas the Beta22 has been engineered for a long time and all the values have been optimized and all the parts have been carefully selected. The Beta22's topology is also more advanced and it helps with the measurements. I really like the design, which is what led me to build it. Another amp I decided to build because I liked the design is the CK2III. I'm expecting good things from it, even though it is cheap and easy to build. Definately since the Beta22 measures so well, it will be my reference amp and the amp I will use to do measurements on my headphones and speakers. We are engineers, we don't listen with our ears, but with our oscilloscopes! Hehe I kid I kid.

One problem I have against the Beta22 is the name. It reminds people of beta software, so people think that it is an unpolished design, but actually it's the opposite of that. Those of you who have actually finished your Beta22 build can happily call it Final22.

 

[MisterX]

Quote:

Originally Posted by philodox /img/forum/go_quote.gif Right now it is FoTM, but as thrice says we will have more concrete impressions once more people get a chance to listen to the ß22.

Do you understand the difference between objective and subjective?

 

[kevin gilmore]

no to much of what cotdt has said.

There are no coupling caps in the dynahi, and it is fully discrete.
The servo uses an opamp and some people build it without the
servo. You could very easily add a servo to the β22 if you wanted
the absolutely lowest in dc output voltages. Schematics of the
dynahi and β22 are extremely similar in many respects. Dynahi is
bipolar output, β22 is fet output. If you want a fet output there is
my new dyna-gbf-fet which measures even better than the β22.
All 3 are excellent amplifiers with high power output, vanishingly
low distortion and very high slew rates. No commercial vendor is
building and selling anything like them.

The σ22 power supply is clearly better and cheaper to build than
the original dynahi power supply.

 

[philodox]

Quote:

Originally Posted by MisterX /img/forum/go_quote.gif Do you understand the difference between objective and subjective?

Shutty...