amp advice

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I am a speaker builder who has just wet my feet in the ocean of amplifier knowledge. I am interested in building a simple, versatile, college student budget, yet high quality amp to run a pair of medium sensitivity 8" two-ways in a small room. I intend to eventually build a larger amp to run the lows and use the amp in question for the highs.

I checked out Randy Sloane's Audiophile's project sourcebook. In these pages he describes his simplest design, the 60w basic EF amp. Kit available at for $95 /channel plus the cost of a power supply, soft start, etc. Will this amp get adequate hf response? It isn't one of his higher quality designs. And, how much more am I paying for the kit as opposed to buying individual parts?

I am sure there are many other amp kits out there, what do you guys recomend?
Thanks in advance,
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Don't rule out doing a gain-clone. For close to the cost of the kit you mention you could have a nice pr of 25 W monoblocs (ie ~$100 assumming you're are good at scrounging for case & heatsinks). The chips can be had as samples if you ask nice, and Steve at ApexJr just got some 120 VA 18-0-18 toroids in that would be ideal (so new they aren't listed yet*). Add some caps, bridges and some passive parts and you have yourself a real nice, REAL CHEAP set of amps.

(* he also got some dual 42 V @ 1000 VA for any of you guys building the monster amps)

The place to go for more info (you'll have to wade thru a lot of posts -- look for Thorsten's inverted schema) is the Amp Chips Forum.

I also have a list of some useful links on my website.

You should give us some more guidelines as to what you're willing to spend, total, because transformer / heatsinks / caps / chassis constitute most of the cost. The other parts are pretty cheap.
Got any spare transformers, heatsinks, or cabinets you can use?
Sorry planet10, I'm not that same Magnus. There are a whole lot of us out there. ;=)

I've mainly been into the Leach Amp and have not yet got into the speaker building area, but I soon will.

bostarob: I'd go for an amp that isn't too hard to build, and preferably a design someone nearby has built. It isn't always easy to get help when you're stuck, even if most of us here try and help as much as we can.

Sorry for the delayed response,
I estimated the cost of the sealelectronics basic ef to be around $400. Let's make that the most I am willing to spend. Of course the less I spend the better. I like $50 a board. No I cannot scrounge for heatsinks as this is my first amp. I can make a chassis, I have a big sheet of diamond patterned alum kick plate (looks very cool and easy to drill). Or I'll just use a shoe box. (joking)
After looking at the leach amp, I like it. It is more complex than the amp I was planning to build, but it also is cheaper and may be higher quality. How many watts does it put out?
Magnus, I want my amp to look exactly like yours. How much did you pay for the entire thing?
Look what this guy did with the leach amp:alt. leach amp

When I first started to build my amp I had contact with Claes Malman (the site you mention), since not all parts are/were easy to find in sweden. He helped me a lot.

I bought my enclosure in a local store here in Gothenburg and the transformer in another place. They were the big investment (toghether with the input caps).

I believe that my amp cost.

* 2 x $50 for the boards
* $60 for the enclosure
* $50 for the transformer
* $50 for the caps
* $30 misc cables and rectifiers
Tot: $300 - $400 since you never buy "only one resistor" or so.

The Leach is one of the best DIY amps you could build. But it may be a bit much for a first time project. Build the ESP 3A instead. Much simpler. Use the alternate MJ21193/94 outputs, two pair per channel, and a 30-0-30 600~800VA transformer. Later build the Leach and bridge the ESP 3A. The ESP 3A will bridge to 400W/4R as described, with the bridging circuitry already on the board.
"djk: where can I find more info on bridging? I'm very new to the concept, so a brief description would be nice. " Read this first
then, if you have a schematic for your amp do this
"The ESP looks perfect, how much do you think it will cost?" The 3A circuit board is USD$17.30 from ESP with a fee of USD$8 for postage. One board will build a stereo amp and self bridge to a large mono amp. ESP will ship up to eight boards for the same fee. Total cost will be largely determined by what you want for a chassis and heatsink, the elecronic parts are all inexpensive.
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