n_maher

Donald, Thank you for sharing the design and your comments with us, I have a few comments. 1. I can assure you that Doug (dsavitsk) was not commenting on the aesthetics of your amplifier. He and I both have a high level of appreciate for clean, straightforward designs both from a circuit and aesthetic perspective. You'll also find that there is a good sized group of us around here who have more than just a passing acquaintance with both design and manufacturing costs. 2. Could you provide a link or further explain the IEC standard for output impedance? All I could find was reference to "IEC 60268-7 Headphones and earphones" which I was not able to access. The 120ohm output impedance sounds prohibitively high to me perhaps even with 300ohm headphones and will almost certainly sound pretty bad with some of the lower impedance headphones we tend to use around here. My own personal amplifier has an output impedance much closer to your 28ohm tap, I suspect that this is what people will end up using exclusively unless they own some of the 600ohm Beyer cans. 3. Your statement "Many headphones are designed and tuned around the IEC spec - now you can hear them as they were intended" doesn't sit particularly well with me. Could you please share whatever research you did to back up that claim? What headphones in particular are designed and "tuned" around this spec? I would have expected that given the proliferation of SS devices that most headphones produced these days (outside the professional studio ranks) would have been designed around a very low output impedance. Regards, Nate

Since I had to break down the speaker rig anyway I decided it was time to update this thread with the tweaks that I'd done to the SImple chassis. Basically I finally managed to make some "feet" for the bottom of the chassis. They are semi-temporary but certainly do the job for now.

Your math sucks.

I wonder if that thing can even turn?

Happy Birthday! This wish is only as tardy as you are filling out your profile!

Well done! Don't forget to register at Head-Fi too.

You have chosen poorly.

The sound might change, to be sure, but a blacker background and lower noise floor? That seems more than just a little unlikely since you have to have a pretty spectacularly shitty amp to have a noise floor with the 650s to begin with.

It is highly unlikely that you'll find what you're after. Balanced DAC's, by default, tend to have a hot output. There's absolutely nothing wrong with the voltage divider approach.

Last day of free shipping on all orders from Woodcraft.com.

Happy Birthday!

I can't see how lacquer would affect a plinth. In an instrument you're counting on the wood to be a part of the equation, in a plinth you're using the mass to not vibrate. Two very different applications one in which I see the finish as an active player (instrument) and one in which I can't see a way it which it'd make a difference. That's my 2c.

Happy Birthday Kevin!

I'm going to go ahead and give you 24hrs to ponder that remark.

Uhhhh, I'm only aware of one that does and it's safe to say that I'll never be able to afford it.

Would it be bad form to show my back up tester?

Indeed, when I bought it (about 2 years ago) it had just been serviced and calibrated. I've also got both the original and a very extensive aftermarket manual for it. I've got my eye on a couple of things and if they pan out I'll let head-case know first.

She is a sexy bitch and one day might be yours...

I'm working on something on that front Jack, if it pans out I may have a deal for you...

That was fantastic.

Shall I expect them shortly thereafter?

I believe the chassis comes apart as you describe, just two front, two rear screws. Everything is generally mounted to the top panel.

Based on the already charred power supply I'd suggest this amp could use a little less 11 for the time being.

Or you could just use the stock transformer for now.