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Ask Rusty Your Own Question
Rusty, Engineer
Category: Home Theater-Stereo
Satisfied Customers: 5888
Experience:  Let my expertise help solve your technical problems. Over 20 years electronics and sound equipment experience.
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Ive got 2 amps & a crossover hooked up inside &doesn't matter

Customer Question

ive got 2 amps & a crossover hooked up inside &doesn't matter whats 1st turned on I get bad feed back what did t do wrong?
Submitted: 2 years ago.
Category: Home Theater-Stereo
Expert:  Rusty replied 2 years ago.
Hello, my name is Rusty. I'm a sound engineer, I can help you. How do you have the amps and EQ hooked up now? Tell me which wire goes to what, or just tell me the model numbers and I'll tell you how they should be connected.
Customer: replied 2 years ago.
crown amp& dbx amp, crossover, bose 901 eq ,pre amp,dbx eq, cd player crown amp 2 jbl18s 2242 dbx amp 2 pair 901s
Expert:  Rusty replied 2 years ago.
Ok, what is the model number of your preamp? The more details I have, the better answer I can provide.
Customer: replied 2 years ago.
cx-3 also the 6 pin plug for the crown into rca's how would that b done im pretty sure I got it rite just in case
Expert:  Rusty replied 2 years ago.
Let's save some time here... Can you give me a list like this so I can fully understand? There is a loop that I need to find, that is causing the squeal. Amp Brand-model numberAmp 2 brand-model numberPreamp brand-model number
Customer: replied 2 years ago.
amp1 crown cdi1000 amp2 dbx bx-3 crossover audio control 2-sx eq bose 901s preamp dbx cx-3 dbx eq 14/10 sonycd player speakers crown amp jbl 2242 2-18s speakers dbx amp bose 901s 4
Expert:  Rusty replied 2 years ago.
Ok, I'm starting to see now. Which amp powers your subs? Are your subs feeding back as well?
Customer: replied 2 years ago.
crown doesn't matter which amps turned on first feed back is still the same
Expert:  Rusty replied 2 years ago.
Let me clean this up so it makes sense. Please verify, it's very hard to read without punctuation, and skipping lines.Crown CDI1000dbx bx-32-sxBose 901DBX cx-3DBX eq 14/10 Is this all of your gear, with correct model numbers, minus the CD player?
Customer: replied 2 years ago.
Expert:  Rusty replied 2 years ago.
Ok, now we have it. The problem is a feedback loop in your preamp. That is what I've been looking for. Connect your CD player to your CD 1 input on the source inputs section of your preamp. Connect the preamp out fronts to your EQ input. Use the white on channel 1, the red on channel 2. Connect the output of the EQ to your 2-sx. Now use the sub output to feed your Crown, and the hi/lo outs to your DBX amp, and connect the speakers respectively. This is a linear hookup, so there is no feedback loop to give you grief. Feedback happens when we start using the record outs and ins. They are made for tape players with an automatic loop disconnect so the feedback doesn't happen. When we use them with any other equipment, we have to be careful of loops. Let me know how it sounds.
Customer: replied 2 years ago.
feed back is coming from 901s
Expert:  Rusty replied 2 years ago.
Only the 901s, so we broke the feedback on the subs? Now let's take a close look at the 901s. Bypass your crossover, go directly from your EQ to your DBX amp, and tell me if the feedback is still there. We're going to eliminate one component at a time until it goes away, then we can take a look at the pinpointed component.