Next step after a cmoy (road to the β22)

[fierce_freak]

I just got back into DIY and want to eventually work my way up to a Beta22 (or maybe something else when I get there

). I'm considering doing a PIMETA or a Kumisa III next, but I thought it'd be best to ask the guys who have walked this road before me. Where should I go next, and what additional stops should be made before going to Beta22 level?

 

[cotdt]

the B22 is not any harder to make than those other amps, so i don't see any reason not to go straight to B22.

 

[Clutz]

In principle it's not harder than any of those amps - but it's a much more involved build. I've built two PPAs, a Millet Hybrid, two Dynalo's and power supplies for all of them and I think the Beta22 is harder. Not because it's that much harder to solder the extra pieces, but becauase the actual assembly and testing is so much more involved.

 

[tomb]

The PIMETA is a good bet. It makes an ideal 2nd build, IMHO. The CKKIII involves a transformer, power wiring and bias trim adjustment - definitely a bigger jump from a CMoy than the PIMETA. After that, if you stay with Solid State, I'd go with the M3 - especially if you're wanting to build up to the B22. At some point along the way, you should work on a parallel journey with the power supplies - probably a TREAD with the PIMETA, at least one for the M3. Then either a STEPS or the Sigma11 as the ultimate source for the M3. You might fit in a PPA at some point, too - to get experience working with matching transistors, etc. You'd probably have no trouble with a B22 after following that path, IMHO.

 

[Nebby]

this is on my to-do list; I think the only part that I'm not too sure how to do is the power supply...but I that's what searching and reading up are for

 

[fierce_freak]

Thanks for the responses, guys. Anyone else should feel free to chime in, too. You can never have too much info (well, you can, but nevermind).

 

[cotdt]

Quote:

Originally Posted by Clutz /img/forum/go_quote.gif In principle it's not harder than any of those amps - but it's a much more involved build. I've built two PPAs, a Millet Hybrid, two Dynalo's and power supplies for all of them and I think the Beta22 is harder. Not because it's that much harder to solder the extra pieces, but becauase the actual assembly and testing is so much more involved.

how is it more involved? all you do is stuff the boards, which any monkey can do. then you test the voltages and try out your amp on a cheap pair of headphones. anyone with an IQ of 70 can stuff all the boards within a few hours. There's no custom heatsinking involved with any of these amps. The only part that takes actual time is making a high quality enclosure.

 

[threEchelon]

You can do anything you set your mind to.

I just finished an M^3 and it's the first time I've soldered or built an amp.

 

[fierce_freak]

Good job

I've no doubt that I can do the monkey thing and put a Beta22 together, but part of the fun for me is understanding the circuit I'm building (and the purpose each component serves). I've picked up a few books that I'm currently reading through, and it's helping. I understand the relatively simple CMoy circuit. Now on to picking the next project, understanding it, and building it. I could probably go right for the Beta22, but that would probably mean my soldering iron is going to sit dormant for longer than if I pick up an intermediate one.

 

[tomb]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif how is it more involved? all you do is stuff the boards, which any monkey can do. then you test the voltages and try out your amp on a cheap pair of headphones. anyone with an IQ of 70 can stuff all the boards within a few hours. There's no custom heatsinking involved with any of these amps. The only part that takes actual time is making a high quality enclosure.

You are not considering the possibility that the monkey could make a mistake. That possibility and its consequences increase exponentially with the complexity of the amp. An understanding is needed when a mistake occurs - both to pinpoint the problem and to fix it.

Add to that any power wiring of the level of house current or more, and anyone with more than a monkey brain understands the consequences acutely. This adds even more pressure in the difficulty of getting everything right without any mistake: injury or death could occur in the worst case, or fire and significant damage in the least case. The monkey brain doesn't realize this and thus, may be at an advantage in this scenario.

 

[j4cbo]

My first headphone amp was a Dynahi, although I'd done a lot of non-audio-related DIY electronics work before.

 

[fordgtlover]

First amp I built after the ubiquitous CMoy was the Pimeta. Stuffing the board was straightforward. However, things got decidedly more complicated when it didn't work.

Troubleshooting and working through the issues as a newbie took some time and some patience, but I did learn a bit. I'd like to see the monkey do that part of it.

I have now just completed, and am casing up, an M^3. The lessons I learned from building the Pimeta sure came in handy during this build, and as a result this amp work first time.

Small steps offer a learning and development path.

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif how is it more involved? all you do is stuff the boards, which any monkey can do. then you test the voltages and try out your amp on a cheap pair of headphones. anyone with an IQ of 70 can stuff all the boards within a few hours. There's no custom heatsinking involved with any of these amps. The only part that takes actual time is making a high quality enclosure.

 

[DennyL]

For those who have trodden this path, I can't resist asking for any comments about the relative sound quality of the M3, Dynahi and Beta22.

 

[Polaris111688]

The path I took on audio was:
CMoy that burned up --> CMoy that worked --> basic PIMETA with BUF634 --> building discrete buffers for that PIMETA --> Millet Hybrid with STEPS for a friend --> PPAv2 for myself with STEPS --> SKA GB-150D power amp with GB-150S2 in stereo configuration

 

[MASantos]

I would go with either the CKKIII or the PIMETA+thread/steps. For the beta you'll need to understand how power supplies work and how to build them, dangers and safety when working around them.

THe CKKIII has the advantage that it will introduce you to biasing in a simpler design so you'll understand what biasg is and how it works, that will certainly be useful for the beta.

All that said, I have build cmoys, alien dacs, pints, steps and pimeta, a millett hibrid. My next projects will be finishing my millett and a few CKKII so I can learn better about biasing and building an all discrete amplifier. After thatI think I'll be ready to go for the beta.