I blew the pre-amp.

What do I need to get to reduce and properly EQ the solar cell output? I need to get it close to the impedance levels on the system.

I was running my amp with the bass "all the way down" and treble about normal. I am happy that I didn't ruin the amp. I thought I had blown the outputs.

For now, there is no sound. Should I give up and go back to a real PA amplifier? I've never designed anything to change the impedance on anything, so I dont know what to do here.

With all the incredible talent lurking all over this site, there has got to be someone that will tell me what to do next.

((Some of you have already told me what to do: buy a real projector!))

I hope that you folks can shed some light on this problem. I will have the receiver running in a day or two. I'll run the Holmes thru another old projector (Eiki) like I used to... Sucky sound!

Oh yeah...The Holmes is still forced to use the Eiki solar cell installed in the PE cell socket. It is going from there thru a small mixer to lower the level enough to not fry the Sony. The bass levels were very hot.

I tried a few days ago to make a cassette recording of a soundtrack so I could hear it later without the drone of the Holmes. The signal was very bass-heavy and low. I was obviously warned then that something was very wrong.

My brain must have skipped a groove. Too much film cleaner?

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I'm assuming you don't have any test eqiupment, so let's test this in a simple way. Get yourself a cassette or reel to reel deck. Hook up your cd player. Run some typical program material (not classical) into it in "record/pause" mode. Set your levels so the signal occasionally tips into the red.

Now, without touching those input recording levels, hook up your Holmes into this tape deck and play something such as a trailer (they're always recorded "hot"). Are the levels pinning the meter? If they are the same or lower, your Sony was ready to die anyway and the Holmes probably wasn't to blame. I'll bet you will find your levels won't even tip into the red, though.

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Actually, even though I have no meter for voltage checking, I have already done the Brad Miller approach. I tried a CD and the record levels. With the levels set at normal for CD's the film sound level was much hotter with bass.

I am sure that the Sony was not getting ready to die again, as the aux input was the only function that died. It's a 4 year old receiver, and other than the trouble that I posted here recently, I've had no problems. I ordered a pair of IC's today that will be here by Tuesday. These both carry the signal from aux in to the preamp input chips. (one each L & R)

My scope (which is junk) showed a signal coming in to each of the IC's and nothing coming out although all VCC voltage is normal. Anyway, the signal was not too hot because I had no problems with clipping, and distortion on high frequencies. I am going to try the resistor, and cap method and see what happens.

I should get a real projector and give up.

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For now, the supply house had one IC for the Sony in stock. The other will be direct shipped to me in a day or so.

My roommate had a suggestion: static.
I dont think so, because there is a 3 prong plug grounding the case and gearcase together, and a wire grounding the amp to the projector in addition to the patch cables. The outlet is properly grounded, too.

Regarding the resistor and cap ideas, try the resistor first. If the bass is still to strong, leave the resistor in place (across the cell) and then put the cap from cell + to the input of the mixer. Wire the low or ground side as normal.

If the signal is still too strong, try using a voltage-divider network, consisting of two 470-ohm resistors in series across the cell. Pick off the line going to the mixer, from ground, and the junction of these two resistors. In other words total cell voltage appears across the combination of the two resistors. By picking your feed across one resistor, you are dropping your input signal voltage by 1/2. Clear as mud?