[sacriste]

I was trying my JMT C-Moy Amp and HD495's from the soundcard output and suddenly a ray of light hit my mind. A heavenly voice said: Try with the speakers too, stupid! I did it and, dear friends, it was amazing! The most noticeable was the clearer bass but everything improved. I was very unhappy with the sound of my Altec Lansing AVS500 and had tortured them with many hours of burn-in, they do improved but this Amp was the real cure. Please, try this at home, you'll be happy!

 

[Persiflage]

I've been using my CMOY with my speakers for about 8 months now. I've always disliked my speakers (Altec Lansing ADA880). I bought them with my computer (through Dell, before I started college). I was young and naieve; they were the most expensive computer speakers Dell had available, so I figured, hey, they must be good.

Well, of course they weren't. They were actually so bad that I at first thought that they were defective, and had Dell send me a replacement pair. After that experience I actually did some research before my first decent headphone purchase, and ended up with the Grado SR-60. I was sucked in from there.

Anyway, my CMOY definitely seems to improve the sound of my speakers. I haven't actually done any A/B with it because my speakers used to be so painful to listen to. Maybe that's something to do over the spring break.

 

[Possum]

Are you still using the speaker's built in amplifier, or did you cut the circuit out and just bypass the speaker drivers to the input jacks of the speakers?

 

[Persiflage]

The CMOY couldn't power the speakers by themselves.

I've set the speakers to a mid level volume, and then use the CMOY to increase the power of the signal before it gets to the speaker's built in amplifier. The one of the main problems with this speaker system was that it just couldn't handle the tiny amount of power that my soundcard gave it. I had to turn the voume all the way up in order to get even a decent volume. I would guess that using a headphone amplifier to amp the signal before it hits the speakers will probably only work with speakers that have a cruddy amplification.

Plus my speaker system has an annoying digital volume system; I much prefer the potentiometer on my CMOY.

 

[archosman]

Dude... u got a dell. Huh huh huh...

 

[chych]

Shoot, I just gave away my speakers (Altec Lansing ADA885s - yeah the THX ones) to a friend (I got them for free anyway) since he would make better use of them... should have tried my cmoy. Oh well he gave me his speakers (Altec Lansing ACS45.2), I should try this later. Then again, I'm about to start building my real speaker system so all this is pointless for me

 

[tangent]

Another good reason to do this is that you can put the amp up on the desk and then be able to swap out the speaker cable for a headphone cable. I have yet to find a set of PC speakers with a decent headphone jack.

I'm doing this one one of my PCs right now, but I didn't bother to A/B test it, because the speakers are just for beeps and bells. I always use headphones for music. I can't test it now, either, because I don't want to wake up the people in the upstairs apartment. (It's 5:30am here now.) But it makes sense to me: a preamp for your computer.

Oh, and Persiflage is right: a stock CMoy type amp can't power unamplified speakers, even efficient PC ones. I've tried it, and even with 80 mA of output power the amp clips badly. It's the low impedance -- just a few ohms -- so you need lots of current. One day I'll get around to hacking up a speaker amp from a CMoy opamp circuit and a bunch of paralleled buffers....