Doug Self Circuits

[steevo]

Has anyone buit any of Douglas selfs power amps or preamp, I have purchased his books but they do not give any PCB layouts.
If anyone has built any of his amp how well do they work. I am thinking of building a multi channel power amp for suround sound with 7 channels.

Thanks
Steevo

[AndrewT]

Hi,
D.Self used to publish PCB layouts, but since he farmed out production to a manufacturer, I suspect he has some kind of agreement in place to protect their income and presumably his licence fee.

[sreten]

http://www.signaltransfer.freeuk.com/

http://www.dself.dsl.pipex.com/ampins/projects/proj.htm

/sreten.

[Conrad Hoffman]

Though he shows very complete circuits, the books are intended to show you how to design, not really to provide a "kit" project to copy except for a couple I believe he has boards for. I've built amps very similar to what he's published, and they work exactly as described- well behaved with extremely low distortion. If you believe that stable well designed amplifiers having specs below some small threshold will be indistinguishable in a properly conducted double blind test, you'll be very happy with his designs. OTOH, there are many who don't believe this, and find fault with the "sound" of the so-called blameless designs. Personally, I learned a huge amount from his books, and provides good information for making choices from various topologies. For me, when an amplifier has a sound of it's own, there's something wrong with it, and the reason is always evident on the test bench, so I'm in the camp of "yes, they all sound the same, if specs are below certain limits, and the amp is operated within its capabilities." My only caveat is that there are a lot more "specs" than most people look at or talk about- see posts here about back-driving amplifiers, RF issues, and differential measurements.

[AndrewT]

Personally, I learned a huge amount from his books, and provides good information for making choices from various topologies.

I agree wholeheartedly.

[martin clark]

I'm in the camp of "yes, they all sound the same, if specs are below certain limits, and the amp is operated within its capabilities." My only caveat is that there are a lot more "specs" than most people look at or talk about

Great observation.

I completely agree w.r.t the comments on D. Selfs articles too.

[streetera]

signal transfer company are currently revamping the power amp and pre amp boards. Once they have I intend to buy and build both. This is on the basis that I learnt a lot from Self's books. Its also a big mistake to not consider the PCB as a critical component in a analogue system so I want that risk removed even if I could (which i can) do the PCB myself. Self talks engineering sense and understand the subtle aspects of second order effects in electronics and knows how to address them. To me that makes him a good engineer and its engineers not audophiles that design and build electronic systems. He also has little time for the pseudo engineering audiophile stuff. (but dismisses it intelligently and logcally). I think its Self who notes that superb audio kit has been designed by engineers who actually never listened to the kit, they just designed it properly such that the aberations introduced were minimised. That approach is good enough for me. but then I am a lapsed analogue engineer (also done a lot of work in SMPS in the past) so maybe this is just saying more about me than him! StreeterA

[wrinkle]

Douglas Self's own pages at Pipex seem to have been down for at least a week now, anyone know what happened?

[DouglasSelf]

Hi

I am painfully aware that my website is not currently accessible under its usual address.The Pipex address translation system seems to have failed, and they just don't seem interested in fixing it.

You can still access it at: http://www.aqpl43.dsl.pipex.com/index.htm

When it will be fixed I don't know- the way Pipex is acting, never. Please pass the alternate address on to anyone you think might be interested.

Spread the word!

[5th element]

Thanks for that, I wondered why I couldn't access your website, google searches failed to find it as well.

I too have learnt a lot from your publications, many thanks for the hard work you've put into the experimentation.