I just bought 2 18" Pyle Subs with a rating of 1800 Watts each. Hooked them up to a 4000 Pyle amp. The speakers are dual voice coil and I have them running at 2 ohms. I have a crossover and 2 batteries in the car. I just repalced the RCA to the crossover from the cd deck. Any way... If I turn the gain up on the amp the speakers go crazy.. Almost like feedback with a microphone if you get too close to a speaker.. They just start hammering. I've tried putting the subs in a 4 ohm load and that seemed to make it worse.. ?? Anything to help would be much apreciated...

by turning the gain up you allowed more noise into the system.

it is best to set the gain low. your subs and speakers will sound much better.

in my own setup the gain is set between 1/4 and 1/2.

the only reason to set it higher is if you are adjusting mulitple amps and want them to play at the same level.

I suggest looking for some tutorials online about gain setting. 

Hi Nick,

 

Are you referring to your home setup or an automotive installation?

 

My S-10 is set at 30% and is more than adequate with the receiver set at 0 db.

 

Jack

 

Jack-

I was referring to my car system, but the same can be said for a HT subwoofer. When I had a subwoofer (which was the S8-APR) for my home system I never had it higher than 1/3. The subwoofer was taken out of the system when I switched to B&W full range floorstanding speakers a few months ago. They can play as nearly as low as the sub did without annoying the downstairs neigbors. Of course, once I am out of the apartment, I will be getting a nice 10" or 12" sub for the system, along with a processor and amps.

Rich:

I just bought 2 18" Pyle Subs with a rating of 1800 Watts each. Hooked them up to a 4000 Pyle amp. The speakers are dual voice coil and I have them running at 2 ohms. I have a crossover and 2 batteries in the car. I just repalced the RCA to the crossover from the cd deck. Any way... If I turn the gain up on the amp the speakers go crazy.. Almost like feedback with a microphone if you get too close to a speaker.. They just start hammering. I've tried putting the subs in a 4 ohm load and that seemed to make it worse.. ?? Anything to help would be much apreciated...

 I'm not huge on car audio, but gain structure follows all types of audio installations.  You should always start with the highest signal level and then increase the gain of the amplifier until it's as loud as it will ever play.  This is a little difficult in HT and Car system without some type of VU meter like pro audio but here is a guideline that should get you in the ballpark.

• Turn the amp channels all the way down
• Turn the preamp volume to 2 o'clock or so
• Start a CD playing.
• Increase the gain levels of the amps until it's as loud as you want it to play, or until clipping occurs and then back it down.

The 2 o'clock position will allow some increased output voltage from the preamp for lower level recordings, but remember that 2 o'clock is probably now the max you ever want to turn up your preamp.  Quite possibly you can't even go that far with hotter recordings, if you hear distortion of any kind, TURN IT DOWN!

 I'm not sure of your crossover type, if it's active or passive, but if that has level controls as well, you want to set them to unity for the input level and use the mid/hi, sub level adjustments for each channel.  Probably by ear at this point...

 That should get you in the ballpark atleast.

Matt

Hi Matt,

 

I figure that Rich does not feel it necessary to respond to your suggestions along with those of James and Nick’s.

 

I was going to ask Rich if he had the speakers in enclosures since those speakers are sold without enclosures. Many years ago I built a 3-Way speaker with 12” bass. Until I placed the speakers in enclosures the 12” sounded like crap but I was just testing them before installation.

 

Jack