n00b in Pass Labs- could use some help...

[trespasser_guy]

Ok, I really haven't looked at this forum more than once before today. I am mostly a headphone amp guy; I build ones with opamps, am planning to build another soon, but have issues with the power supply that I am taking care of first.

I recently got into the pc board design area, which is why I am here.

I noticed that many people here make their own boards for these circuits. Are they just a really rare and good design? Expensive?

I want to do somehting worthwhile... something I can spend a few hundred on, build it from the ground up in a big, imposing looking case and then be proud of. I can sort of do this with my headphone amps- I designed my board, and many others for that matter. It would be cool. I wanted tubes, but just don't know enough about them and am afraid of having >200V run across my headphones in the event I screw something up.

So, I could use something like this for my home theatre. Make a nice 5-channel amp or something. Is this plausible? Am I too, uhh, under-educated for this? Where is a good place to start learning? How much would I have to spend?

Thanks all

 

[joke]

I think you are at right place
You can learn a lot about building amps here and there is lots of great people willing to help you with yours questions...
Amps from mr. Pass (Aleph 2,4,5,3 or 60,30)are ease to build and do not nead no adjustmant, so you just nead to put it together and plug it in ...
About home theater with Pass amplification , I don't know ... bacause it produce to much heat,it could be problem,but if you got right heatsinks that would not be the problem...and they got to be BIG...

Josip

 

[joke]

By the way you can find some articals on www.passlabs.com
and there is service manuals for Aleph amplifiers...

 

[JDeV]

For Home theatre amps, very easy to build, no big heatsink issues, relative low parts cost, ideal for beginners - if you are - I would suggest the opamp "Gainclone" option. More info on that here:

http://www.geocities.com/rjm003.geo/rjmaudio/diy_gc.html
http://home.student.utwente.nl/f.s.bouwman/audio/thor-amp.html
http://www.euronet.nl/~mgw/diy/amps/uk_geenkloon_1.html
http://www.diyaudio.com/forums/showthread.php?threadid=9112
http://diyaudio.com/forums/showthread.php?threadid=9270

Enjoy and good luck

 

[Variac]

I'm sure you will get better responses, but I can address some of your questions.

The circuit board question is a little unclear to me. Sometimes people here make their own boards because they want to.

For the more popular amps, there are usually mail order sources for them. A recent trend is a group of us gretting together to order a bunch of copies of a board that one of the members has layed out. Another option is that members that have layed out boards will usually send you the files in order to reproduce them.
Making your own board designs from scratch is certainly the true DIY way, so is very respected around here..

The Pass amps have a tremendous reputation for sound quality. Each amp model tends to have stronger and weaker points. One of Mr. Pass's design tenants is to use simple circuits, so his designs are pretty easy to duplicate. This is further helped by the fact that he is on line all the time HELPING us replicate his designs. A generousity that has been commented on here often.

He has a web site just for DIY people: passdiy.com
where he has posted various designs also.

The Pass designs are all Class A which means they are all pretty inefficient, which means lots of heatsink area, So, yes you will have an imposing amp. In fact it would be hard to get enough heatsinking on one chassis for a 5 channel with more than about 10 watts/ch.

The parts cost can be pretty high, but the factory amps sell in the 5k plus (sometimes plus plus!!) range at a store. A pair of 100 watt Aleph 2 monoblocks would cost at least $600 to make with surplus parts. The major cost is the heatsinks!! There are much more modest designs at the website so check them out. Also a gallery of successful DIY projects- a lot of creative variety there!

Anyway, I'm sure these off the top of my head comments will be corrected by others, but I wanted to encourage you to pursue this path. I think you are in the right place for what you said you want.

 

[JDeV]

For Home theatre amps, very easy to build, no big heatsink issues, relative low parts cost, ideal for beginners - if you are - I would suggest the opamp "Gainclone" option. More

If you of course want to do some "building" the Pass DIY projects offer a variety of nice circuits. There are also plenty of advice always available. A fact is that you will require plenty of big heatsink, lot of big caps and fat power transformers.

Maybe you can be more specific on your budget and power output requirements to get better suggestions.

 

[trespasser_guy]

I am generally a tight budget DIYer, but I really want a project I can work on for quite a while. Thsi way I will always have something to do when I have nothing to do.

I haven't looked at any of these designs, but will do so now.

I probably will make my own boards too. Just for fun. I make random circuits when I have nothing to do.

I am sure I will have many more questions once I look at some circuits.

Thanks for the help thus far!