Carver Amazing Originals - possible crossover issue???

Hello - I was recently blessed to be able to pick up a pair of original Amazing's in very good condition. This is my first go around with Carver equipment and vintage for that matter, so I am seeking guidence. I am grateful that this site is here! One speaker plays perfectly; but with the other the woofers play fine, but the ribbons do not play at all. Of course I knew this upon purchasing them, and just assumed I would replace the ribbons - no big deal. I tested resistance, and 1 panel measured fine, while the other did not measure at all. Seeing that the ribbons looked like they had seen better days, I went ahead and had James in FL make me a new pair. I figured I'd be in good shape. So I came home last night all excited and soldered in the new panels, and to my surprise the panels still did not work! It seems I didn't realize that I had to have the panels connected to get resistance from both. Like I said I am new to this so please excuse my ignorance.

So what to do now? I have 2 brand new ribbons and 4 woofers that look great. Should I inspect and possibly swap the crossovers? How difficult is it to solder the x-over in and out and can they be swapped to work in the L or R speaker? The guy I bought these from had them sitting in a AC controlled room for 6 years with no play. Apparently he was playing that loud 6 years ago and he hurt something and then the one speaker's ribbons just stopped playing. Please help me troublshoot this issue. Thanks, Jeff

Here is the link that will help!
http://arafel.org/audio/als/index.html

post a pic of your xover.
I bet its a bad cap.
C1 would be the 1st to check. 85uf 100v. you can jumper this, just dont play it loud
then check R1 .5ohm 50w see if this open
the other parts are notch filters.
you can swap the xover to the other speaker, but it will take a bit of work.
if ya do this, write down and take pics, these will be your friend when ya do this,......

Welcome

Welcome

I see you are in Tampa. I am just down in Sarasota.

Welcome, G!

post a pic of your xover.
I bet its a bad cap.
C1 would be the 1st to check. 85uf 100v. you can jumper this, just dont play it loud
then check R1 .5ohm 50w see if this open
the other parts are notch filters.
you can swap the xover to the other speaker, but it will take a bit of work.
if ya do this, write down and take pics, these will be your friend when ya do this,......

Thank you for all of this information! I will get to work tonight hopefully.

Why not just play a little quiet music (classical piano) through the ribbons with no crossover attached. THat will validate a crossover (vs. a wiring) problem.

Why not just play a little quiet music (classical piano) through the ribbons with no crossover attached. THat will validate a crossover (vs. a wiring) problem.

thats even better...
why didn't I think of this....

Why not just play a little quiet music (classical piano) through the ribbons with no crossover attached. THat will validate a crossover (vs. a wiring) problem.

I just finished doing this (minus the classical). I used Diana Krall instead as she was an arm reach away. The ribbons are working fine. The issue is somewhere in the crossover. I have it out of the speaker now and inspecting closely. Nothing looks burnt at all. Everything seems to be wired together so I am not sure what I am getting a reading from without taking it all apart which I am definitely not comfortable with yet. One thing for sure is, the woofers play fine and ribbons do not (through the crossver that is), so I am focusing on the caps and notch filters on the side of the panel lead wires (bottom right corner). Thinking of taking (or sending) it to someone that knows what they are looking at.

Why not just play a little quiet music (classical piano) through the ribbons with no crossover attached. THat will validate a crossover (vs. a wiring) problem.

I just finished doing this (minus the classical). I used Diana Krall instead as she was an arm reach away. The ribbons are working fine. The issue is somewhere in the crossover. I have it out of the speaker now and inspecting closely. Nothing looks burnt at all. Everything seems to be wired together so I am not sure what I am getting a reading from without taking it all apart which I am definitely not comfortable with yet. One thing for sure is, the woofers play fine and ribbons do not (through the crossver that is), so I am focusing on the caps and notch filters on the side of the panel lead wires (bottom right corner). Thinking of taking (or sending) it to someone that knows what they are looking at.

Well, I'm looking at the schematic right now, and there is a 85µF capacitor connected to a ½Ω resistor (probably two 1Ω resistors in parallel). I'd measure that ½Ω resistor to see if it is open (same with the capacitor). On the other side of that resistor are the two notch filters. Each of those has an LRC parallel circuit, which means each has an inductor in it which will pass DC with very little resistance (and the capacitors will block). From the point beyond the ½Ω resistor to the attachment to the ribbon should read around 4Ω (my calculation came out to 4.27Ω). In the schematic I'm looking at, the ribbon is connected to the crossover on the negative side (black).

hey Bill,
how do you get the ohm symbol from your keyboard?

Ω

Why not just play a little quiet music (classical piano) through the ribbons with no crossover attached. THat will validate a crossover (vs. a wiring) problem.

I just finished doing this (minus the classical). I used Diana Krall instead as she was an arm reach away. The ribbons are working fine. The issue is somewhere in the crossover. I have it out of the speaker now and inspecting closely. Nothing looks burnt at all. Everything seems to be wired together so I am not sure what I am getting a reading from without taking it all apart which I am definitely not comfortable with yet. One thing for sure is, the woofers play fine and ribbons do not (through the crossver that is), so I am focusing on the caps and notch filters on the side of the panel lead wires (bottom right corner). Thinking of taking (or sending) it to someone that knows what they are looking at.

Just bring it down and we can trouble shoot it here... If worse comes to worse, I'll swap you for our working crossovers while I replace whatever needs to be replaced. Bring them both, ill do both of them at the same time, and they'll last you another 20-30 years

James

Well, I'm looking at the schematic right now, and there is a 85µF capacitor connected to a ½Ω resistor (probably two 1Ω resistors in parallel). I'd measure that ½Ω resistor to see if it is open (same with the capacitor). On the other side of that resistor are the two notch filters. Each of those has an LRC parallel circuit, which means each has an inductor in it which will pass DC with very little resistance (and the capacitors will block). From the point beyond the ½Ω resistor to the attachment to the ribbon should read around 4Ω (my calculation came out to 4.27Ω). In the schematic I'm looking at, the ribbon is connected to the crossover on the negative side (black).

Bill - thank you for this information. Ok, I see the 85µF capacitor and it is indeed sitting atop dual 1Ω resistors. The yellow caps and notch filters on the right side right test out fine. I tried to get a reading from the light blue 85µF capacitor you spoke about, as well as the resistors and the two notch filters just to the right. I am not getting a reading from any of these. It seems that anything along the chain of the black wire that runs from postion 1 on the bottom right over the position 2 on the bottom left, and then back up to position 1 just above that at the top, is reading healthy. In summary, it does seem to be what you mentioned but what now? Do I have to replace all of these or just the 85µF capacitor?

Gpowered.......

so could you do me a favor, when looking from the rear of the speaker, can you tell me what side the red wire is hooked to on your ribbons, R or L. and where does this wire go, does the red wire go to the capacitor side of the x-over, or to the shared - common point, this wire would then go back down to the neg side of the binding post....
pics.....

thanks....