Can you suggest a new project for me?

If you want a three-channel build, how about a M^3? Sensationally good amp.

For something a little simpler, a CK2III is nice because it has its power supply on board.

You might want to look at the Bijou - another good one if you're interested in tubes.

If you want to go further afield, consider one of the tube amps at HeadWize. Build it point-to-point. You'll be challenged, but it'll force you to translate a schematic to the real world. Think about it as putting a jigsaw puzzle together. You can do it. Not as simple as a PCB, but once you "get" it, you'll be able to build all sorts of cool stuff. It's worth the time investment.

Push your comfort level a little bit and remember that the DIY Forum is here to help you.

Hi newbie91, I'm in a very similar scenario to you, but perhaps a little further down the line in the projects I've finished.

 

I brought Paul Scherz's Practical Electronics for Inventors (2nd Ed.) to help me get to grips with the fundamentals. This is a fantastically comprehensive book and has been a real asset in my learning. The only thing I would say is, it's a little heavy on the maths, and if you don't have any mathematics knowledge beyond the basics (which I don't) then you might struggle, as sometimes the book uses math as an intrinsic part of the explanation (which is fair enough as maths is a core part of EE). I overcame this by supporting my learning with other sources on the Internet. For example, there are a great number of videos on youtube about electronics fundamentals, some of them really effective in how they explain things.

 

Like you, my first audio DIY project was the CMOY. Next I built the AMB Mini³. In someways, in terms of the actual build, the Mini³ was easier than the CMOY because it was highly integrated (no wiring or difficult case work) and has a PCB, making part location, etc. a lot easier. However, building the Mini³ is a great learning project as it's a good deal more complex than the CMOY and AMB's documentation and support is second to none, in my opinion. The Mini³ is also a great sounding and refined portable amp to my mind - it blows the CMOY away (which is to be expected, and isn't a criticism of the CMOY). There are a number of build threads for the Mini³, located here on Head-Fi, Headwize and AMB's own forum. I read through all of these before embarking on this build and I learned a great deal, not just about this particular project but about DIY audio and amplifier design in general.

 

After that I built the AMB M³, a desktop, three channel, mains powered amp. As Uncle Erik has stated, this is potentially a great next project given your specified requirements. The M³ is step up in difficulty from the Mini³ in my opinion, mainly on account of the fact it's a less integrated design (by virtue of it's intended application), the case work is more involved and - unless you buy an off-the-shelf PSU - involves mains AC wiring. AMB also provides a PSU project for this (and other amps), the AMB σ11. Again, this is remarkably well documented and supported project, and the build threads are another gold mine of information.

 

Good luck and please share your progress with us!

 

There are a few things you have to realize.

First, lets get out of the relm of headphones and just talk about speakers.

 

A speaker has two poles. "positive" and "negative" (it's Alternating current, so this isn't really true.. but we'll just call them that)

 

Ussually, we amplify the positive end, but there isn't any reason we couldn't just amplify the negative end.

There is also no reason we can't amplify both ends... basically providing twice the power.

 

 

Now, with headphones we have two speakers.

"2 Channel" - amplify the two positive ends as normal.

"3 channel" - amplify the two positive ends and also the common negative end.

"4 channel" - amplify the two postive ends and seperate negative ends.

 

Hopefully that'll get you started

 

About your original question: realize that building a CMOY is more difficult than most of the simple PCB amps.. et al Mini^3

The answer to your question relies heavily on budget considerations.

 

For instance, if your budget is lower, I would recommend a P2P 12au7 Starving Student Millet Hybrid. (Last I checked, costs about ~$60 or so these days)

If your budget is a bit higher, consider M^3 or dynalo.

 

 

Edited by nullstring - 5/25/11 at 9:34am

no probs . A succinct description of the benefits of the three channel active ground topology can be found under the tech highlights sections of AMB's M³ website:

 

Edited by jr41 - 5/25/11 at 10:08am

Lol, not that easy.

With SPDIF (optical) input the signal is digital.

In order to get an analog signal from that you'll need a DAC. (digital to analog converter)

 

A DAC is another project (or product) in it's entirety... and require their own budget.

 

This isn't even close to a conclusive list, but take a look

http://www.audiokarma.org/forums/showthread.php?t=275123

 

Anything that outputs sound from a digital file/media has a DAC in it... so you're already using one (most likely) (ie. iPod, CD Player, sound card, etc.)

However, it's not likely of very good quality.

 

The best means I know of powering the M³ is the σ11 -  it's a very quiet and low output impedance PSU, probably the two most important factors in a PSU for audio amplification. It's advisable to keep the PSU and amplifier in separate cases, this prevents the PSU EMF contaminating the audio signal.

 

Optical is a digital signal interface, an audio amplifier is an analog device. The two signal types are not compatible in this application. You would need a DAC to convert the digital signal to an analogue signal. Most DACs have an optical interface, along with co-axial and USB. Guess what, you can build a DAC too . I would recommend spending some time generally browsing Head-Fi to gain a more fundamental understanding of different sources, amplifiers, etc.

 

It took me six months of reading and completing simpler projects before I felt confident enough to take on something like the M³, so your plan to read up first is a good one, and will hopefully save you a lot of frustration and unnecessary expense.

Although I have no experience with the M^3, here are my thoughts...

 

The M^3 is not top of the line any more.. There are many DIY amps that far succeed it.

 

 

I feel like the Sigma11 power supply is overkill for it. (Also came out after the M^3)

When/If I make an M^3, it'll have a smaller regulator in it.. so it can be a smaller unit that I can put on my desk at the office, etc.

 

However, you should your own research and come to your own conclusions.

This is just food for thought.

Edited by nullstring - 5/25/11 at 2:28pm

this goes on to a much much greater degree within your PC.

 

 

As far as amps succeeding it..

 

Beta22, EHHA, Bijou, for starters.

 

There are plenty more.. 

Here's a list of DIY amps to look into.

http://www.head-fi.org/wiki/list-of-diy-headphone-amps

 

However, I wouldn't go much further than an M^3 with the experience you have. 

 

The cost of an amp isn't a great determiner of how good it is.

However, It doesn't make sense for someone to design an amp that cost more and has lower performance than a competitor.

So, you can kinda of use cost a little bit... and then dig deeper into everything.

 

Also, some amps are better for certain headphones, etc. For the three I listed, I doubt you can really say that one is really better than another.

Any interest in a tube amp?

 

There's a kit available that makes for a relatively simple build: http://beezar.com/catalog/product_info.php?cPath=37&products_id=125

 

I built one a couple of years back. Sounds pretty sweet to my old ears.

 

Some of the pluses:

- No tiny surface-mount ICs to solder.

- Lots of online help.

- Comes with a custom chassis, which can save a lot of time & effort.

- Uses low-voltage tubes, so there's less chance of getting ZAPPED.

 

More info here: http://www.diyforums.org/MiniMAX/MiniMAXoverview.php

 

Good luck!