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I found two Fisher cabinet style speakers at a yard sale for $20.00. Three speakers in each cabinet. They work fine.
I want to find an amplifier so I can use them with my PC. The speakers are Fisher Model # DS-825, 8 ohm, input power 10-100 watts, crossover? 1.5/6 khz.

I found this "Pyle" mini amp on Amazon and I am not sure if it will work. Here is the link.

http://www.amazon.com/PCA2-40-Watt-Stere...6253&sr=1-2

Any help or suggestions appreciated. Thanks John

That should do it.

I got a nice amp at Goodwill for a few bucks tho.

Greg,
Goodwill? I had no idea. I have never been inside a Goodwill store. My wife goes to all those type stores. I thought it was just clothing?
I just happened upon the speakers as I was driving by a house.


Will the 40 watt output from the mini amp, drive the 10-100 watt speakers enough to improve the sound verses PC speakers? Will it be loud enough?

I guess I could find another used/old stereo amplifier instead and get the 100 watts instead of the 40 watt? But the 40 watt is available right now. $45.00
Whats your suggestion? I hope I am making sense with these questions?

Thanks Very Much..........John

It all depends on how close that is to actually being 40 watts. My guess is it will probably be OK. "100 watts" in the olden days was usually a fantasy. I am driving some pretty big "disco era" speakers with a pretty modest amp. The actual silicon is pretty cheap these days.

Thanks Greg.

Greg,

I got the 75 watt model for a few more bucks. Found out afterwards it is 4 ohm amplifier and my speakers are 8 ohm. Manufacturer says no problem and so does the community forums. Your take? Yes? No?

4 ohms would allow you to put 2 (8 ohm) speakers in parallel on the same channel.

I read a little about that amp you were looking about and it is 40w "max" whatever that means and the consensus is that is really about 8w RMS. Unless you are in the Hollywood Bowl that may still be plenty. There has been so much lying going on in the amp business, for so many years, it is not clear how much power is really enough.
If something has a heat sink about half as big as a beer can on each channel, I figure it is big enough for me.

The 40 Watt Power Amp's Data shows 40 Watts Max into a 4 Ohm Load.
If this Power Amp drives an 8 Ohm Load, the Max will be 20 Watts.

Now, if this Amp can continually push that 20 Watts into the Woofer (largest Speaker) via a Digital'ish signal, that will be quite thumpy!

Unless you really want "noticeable" Low Frequency response, the 20 Watts per Channel - 2 Channel Output from this Power Amp should be fine.

As mentioned by Greg, the RMS "Actual" (continuous) Power Output for this Amp is 8.0 Watts into a 4 Ohm Load - which loosely translates to 4 Watts into an 8 Ohm load.

From the looks of the Amp's design, I would say this RMS Power would find it's way into the Mid-Range and Tweeter Drivers most of the time - with the Transient Max Power pulsing the Woofer for very short bursts.

Hopefully the High End (Tweeter) Driver has a proper Crossover!
Power Amps with low output Power ratings tend to fry Tweeters (Tweeters resonate "easier" with very simple Crossovers and low power amps).
Cheap-'o Capacitors exacerbate the issue - until the Cap pops!

For fun... to "clean up" the signal leaving the Sound Card, Pre-Amp the signal with a 10 Octave Graphic Equalizer.
Bypass the E.Q.s on the PC (i.e.: Windows Media Player's Equalizer) by placing all the slide pots at the center "0" position.
Only Equalize the signal through ONE EQ! Things begin to sound very crappy when Two or more EQ's are working on the same output signal!

This just in...
I just noticed the power Amplifier you obtained is rated for 75 Watts into a 4 Ohm Load.
This should give you around 38 Watts Peak into your 8 Ohm Loads (Speakers), with a continuous RMS Power of around 9 Watts. Again, these are "Per Channel" ratings.

There are many different Tweaks which may be applied to an Audio System... some are intense (read: lotsa' $$$), others are quite modest (read: realistic, with good quality sound, not lotsa' $$$).

Good luck with your Digital Audio Quest!

-- Scott

Forgot this...



These are the "Roll-Off" points for the Mid Range Driver's Crossover settings.

In a Nutshell, the "1.5 kHz" is the Low-End Rolloff Frequency for the Mid Range Driver, as set by the Crossover design; and the "6 kHz" is the High-End Rolloff Frequency.

The Crossover will "Bandpass" the range between 1.5 kHz and 6.0 kHz through the Mid Range Driver (the "middle" Speaker in each Enclosure).

Frequencies < 1.5 kHz become attenuated at the Crossover, and will be Low-Passed through the Woofer Driver - via the Low Hz Crossover section (if included...).

Frequencies > 6.0 kHz become attenuated at the Crossover, and will be High-Passed through the Tweeter Driver - via the High Hz Crossover section.

-- Scott

I went for the "low tech" option with my desk-top computer here.
I have the Line out feeding the auxillary input of a 1980's Philips "ghetto-blaster" radio/cassette unit (remember them?).
This has treble, bass and balance knobs and a knob that you can adjust the sound all the way from Mono through to "Spatial Stereo", this has to be heard to be believed.
They just don't make gear like this any more, what's more it didn't cost me a cent, it was going to be thrown out as it didn't work.
I soldered one of the secondary wires from the transformer back on to the main PCB and we were in business again.
Here's a picture of it:

I got one of these out of a dumpster.

http://www.hometheaterhifi.com/volume_7_1/b&k-avr-202-receiver-3-2000.html

Damn,
That is a NICE bit of kit, Greg,
Was there much wrong with it?

Just a few scratches on the case. It seems fine. This was my wife's HOA and they just wanted something smaller and lighter for outside events. Most of the time they are using the "house" PA system anyway. That is probably not as nice an amp as this but they are pretty dumb there. Easy seems better than "better" to them.

Awesome Score Greg!
Cosmetic imperfections mean nothing, with a solid Power output!

Mike,

I like your Ghetto Blaster version!
Those Tweeter Horns must spread the high ends quite well!
The Voice Coils on the large Speakers appear to be 35 Watt (sizes in Image compared to Tape Deck Take-Up Reels).

You Guys have me contemplating a "Beefier" Audio System for my PC...
Have a 200 Watt x 4 Channel Audio Power Amp collecting dust, which might find its self driving some custom boxes very soon!

-- Scott

I have 3 PCs in the house that are primarily media boxes so they are all hooked to something. The "TV" PC goes into my big screen that also feeds a number of smaller "PC speakers" around the house and the RF for my head set. The inside music PC feeds that big honker amp and the one on the tiki bar outside feeds a fairly modest amp that drives a couple of big old disco era speakers loud enough to disturb the neighbors if I want. ... and the nearest one is 300' away.

Hey Scott!,
Yeah this radio unit, for the size of it is rated at 55W RMS.
I've used it the odd time as a make-shift bass amp during jams at work on a Friday night, with a 5-string bass on the end of it (quite an ask for a thing with such small speakers) but it sounds great, it's handy to have some sort of tone-shaping available over what the guitar gives you.

I just wish someone could teach the manager of the Fitters how to sing!