How should I sell my homebrew amplifiers?

[cheesehead]

After three generations, I think I've designed an amplifier module that works. Based on the LM3875, it's a traditional "gainclone" amp, with the following features:

-30w per module. (These things are great for bi- or tri-amping.)
-Low cost - I can keep the cost as low as 10$/module for parts and PCB, although this is only if I buy in bulk.
-Size - these things are about 2.5" x 1.5" x 1". Of course, you need a heatsink, which makes it much bigger.
-Quality - these amplifiers, if built right, can have a THD+N of well under 0.1% through 20khz. To give you a rough idea, most amps have a THD+N of 1-2%, and car amps can be as high as 5%.

Anyway, I can manufacture either kits (add your own PSU/preamp), "complete" kits (includes PSU without transformer), "deluxe" kits (includes simple stepped attenuator or potentiometer for use as passive preamp), and "Super Deluxe" (includes PSU, preamp PSU, attenuator, and class-A transistor buffer).

I could also make completed modules, or just sell the amps ready-to-go.

There are, however, a few quirks.

1. No protection, so if you're not careful, you can drive your amp or speaker to clipping pretty easily. Unless you're careful and/or know what you're doing, you can fry the amp.
2. Not super-high-power. These are rated into 56 watts max into 4 ohms, but most people get no more than 30. As a result, you can't drive your Martin Logans.
3. Amplifier "hum". Gainclones seem to be extra-sensitive to just about everything. I put my PSU in a seperate box entirely.

NOTE:
Gainclones do NOT require fancy-pants cables. Cat5e is the reccomended speaker and interconnect wire, especially the shielded stuff. That said, I'm just going on what I've heard - I use zip cord.

So, what do you think I should do? I'm about to make another prototype PCB, which is essentially a re-worked version of the 3rd generation design that does'nt need a jumper, and seeing as how the 3g amp worked (though I accidentally cooked the chip I had in it), this one should work even better. A kit (two mono amp modules) with PSU parts would be about 40$; a completed and assembled amp (ready to go) is about 120$-250$ depending on what you want in it.

 

[Unheard]

Set yourself up a basic little e-commerce site combined with eBay sales. That will get you a start. You may also consider sending out some samples to reviewers, try to get some name recognition.

 

[cheesehead]

Originally posted by: Unheard
Set yourself up a basic little e-commerce site combined with eBay sales. That will get you a start. You may also consider sending out some samples to reviewers, try to get some name recognition.

I'm a student. I was just hoping to bodge a few together, and maybe sell 'em through the B/S/T forum.

You can, however, see a very similar design here:

Link to review, specs, and more.

My modules, though less snazzy, can be made up very cheaply using 1% and 2% Dale metal film resistors, Nichicon low-impeadance caps, and WIMA metal film caps for bypassing. All on a single-sided PCB.

The primary draw of these amps is their "neutrality" - they do almost nothing to the signal. Tube amps can actually have a lot of distortion, but it usually makes the audio sound better, not worse. The "gainclone" is designed to have almost no distortion at all - it just amplifies the signal.

The big difference between my design and those above is that I have a much bigger set of PSU capacitors (12,000uf for two channels vs. 1,000uf per channel) and an inductance-limiting "snubber" circuit to keep the amp from sounding scuzzy. This can help with bass a bit, and it means that I can use much less expensive capacitors. (They're surplus Nichcons - you'll find caps just like them on all sorts of expensive stuff, from radios to NF7's.)

Yes, I spent a lot of time on the design, and yes, there are probbably other, better designs out there. ChipAmp.com sells excellent stuff, but they're very often out of stock, and don't sell completed amps.