Need opinion on good 3000+ amp

[Bobbytwonames 5,000+ posts]

47hz... 2700 clamped. It got down to 28hz but my cabin liked 47 tuned 38hz. So theres your freq.
I'm not a rebassed low lows freak. I enjoy rock music... And watching the wipers bounce occasionally. Glass costs, hinges too... Etc.
It was fun hitting those #. I won't lie.
But anymore the whole thing is... Yuck.
Abandoned and shelved. I gifted most my audio away.
A strong deck mated to sensitive speakers does the job.

I would rather hit 150+ @ 33 hz. then 152 @ 47 hz.. what about you? Which one is harder to hit?

 

[Blackout67]

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I ended up getting the SIA-2500. It puts out good power on my stock electrical with the gain adjusted accordingly. Have it on my American Bass Hawk 1244 in a box I built 2.0 net tuned to 30hz 24 inches of port area. The only problem I'm having is that the sub is playing well above 80hz which is the crossover point I have set on my headunit. I noticed it because I was watching it while the intro to a song was playing and before the bass dropped I could see the cone moving with the vocals slightly. So I went on my frequency generator and set the frequency to 120 and it was coming thru the sub nice and clear so I went to my amp to check the crossovers and they looked fine. So I turned both the low pass and the high pass to their lowest settings and it did nothing. So I went back to the headunit and set the lpf to 30hz and it made most of the high frequency go away but I could still hear lower male vocals.

Any solutions?

 

[Bobbytwonames 5,000+ posts]

FOLLOW UP



I ended up getting the SIA-2500. It puts out good power on my stock electrical with the gain adjusted accordingly. Have it on my American Bass Hawk 1244 in a box I built 2.0 net tuned to 30hz 24 inches of port area. The only problem I'm having is that the sub is playing well above 80hz which is the crossover point I have set on my headunit. I noticed it because I was watching it while the intro to a song was playing and before the bass dropped I could see the cone moving with the vocals slightly. So I went on my frequency generator and set the frequency to 120 and it was coming thru the sub nice and clear so I went to my amp to check the crossovers and they looked fine. So I turned both the low pass and the high pass to their lowest settings and it did nothing. So I went back to the headunit and set the lpf to 30hz and it made most of the high frequency go away but I could still hear lower male vocals.

Any solutions?

I leave the crossovers on my SIA wide open and only use the crossover on my HU. I set my HU to 70 hz.

 

[Bobbytwonames 5,000+ posts]

FOLLOW UP



I ended up getting the SIA-2500. It puts out good power on my stock electrical with the gain adjusted accordingly. Have it on my American Bass Hawk 1244 in a box I built 2.0 net tuned to 30hz 24 inches of port area. The only problem I'm having is that the sub is playing well above 80hz which is the crossover point I have set on my headunit. I noticed it because I was watching it while the intro to a song was playing and before the bass dropped I could see the cone moving with the vocals slightly. So I went on my frequency generator and set the frequency to 120 and it was coming thru the sub nice and clear so I went to my amp to check the crossovers and they looked fine. So I turned both the low pass and the high pass to their lowest settings and it did nothing. So I went back to the headunit and set the lpf to 30hz and it made most of the high frequency go away but I could still hear lower male vocals.

Any solutions?

Like this.

 

[hispls 5,000+ posts]

Hmm.. Well every time you drop the ohms the damping factor is cut in half.. So if you want your damping factor to remain high as possible you would be wanting to run higher ohm loads to achieve this.

Correct, but he still hasn't bothered to just do a google search and take 10 minutes to learn what it even means. But I guess people who really care will buy an expensive amp and run it at .5 ohm for the damping factor.

 

[Buck 5,000+ posts]

FOLLOW UP



I ended up getting the SIA-2500. It puts out good power on my stock electrical with the gain adjusted accordingly. Have it on my American Bass Hawk 1244 in a box I built 2.0 net tuned to 30hz 24 inches of port area. The only problem I'm having is that the sub is playing well above 80hz which is the crossover point I have set on my headunit. I noticed it because I was watching it while the intro to a song was playing and before the bass dropped I could see the cone moving with the vocals slightly. So I went on my frequency generator and set the frequency to 120 and it was coming thru the sub nice and clear so I went to my amp to check the crossovers and they looked fine. So I turned both the low pass and the high pass to their lowest settings and it did nothing. So I went back to the headunit and set the lpf to 30hz and it made most of the high frequency go away but I could still hear lower male vocals.

Any solutions?

Is there a db/octave slope setting on your crossover? Are you sure that head unit crossover applies to the sub amp RCA’s or is it just the sub amp’s crossovers you’re having issues with?

 

[Blackout67]

Is there a db/octave slope setting on your crossover? Are you sure that head unit crossover applies to the sub amp RCA’s or is it just the sub amp’s crossovers you’re having issues with?

Yes because the crossovers worked fine on my SFB2k

 

[Buck 5,000+ posts]

Yes because the crossovers worked fine on my SFB2k

Are you saying, also, that your sub amp crossovers (on the amp itself) aren’t working?

 

[Blackout67]

Like this.

View attachment 40527

Got it. Also when you received your SIA was the bass boost maxed out? My **** was clipping so fast I thought I got an amp with a short until I turned off the bass boost

 

[Blackout67]

Are you saying, also, that your sub amp crossovers on the amp itself aren’t working?

Sorry didn't word that well. What I meant to say was I had the crossovers set the same way on my headunit and my old SFB2k and I did t have this issue. The slope on my headunit is set to the default -12db

 

[Buck 5,000+ posts]

Sorry didn't word that well. What I meant to say was I had the crossovers set the same way on my headunit and my old SFB2k and I did t have this issue. The slope on my headunit is set to the default -12db

Set that at -24 db, if you can. Is the head unit only a low pass filter? Do you have crossovers on your amp?

 

[Blackout67]

Set that at -24 db, if you can. Is the head unit only a low pass filter? Do you have crossovers on your amp?

Yea it only has lpf that I can see for the sub. It's Kenwood unit. The amp has crossovers, but last night they didnt seam to do much. It's the same layout as the picture that Bobby posted

 

[Blackout67]

I leave the crossovers on my SIA wide open and only use the crossover on my HU. I set my HU to 70 hz.

Does your head unit have a subsonic filter? If you have your crossover open wouldn't it be bottoming out hard on notes below your tuning?

 

[Buck 5,000+ posts]

But I guess people who really care will buy an expensive amp and run it at .5 ohm for the damping factor.

I’ve heard a difference between amps with higher/lower dampening factor play low notes differently (in the high 20’s tuned at 34 hz). I’ve directly tested that in my own vehicle, with all variables the same, at 1 ohm. The amp with the ~250 damping factor played 2-3 hz lower than the amp that had about 100 damping factor. There’s soooo many factors to this, to know if you need a higher damping factor or could benefit from it. I needed it running .7 ohms per amp and playing 25 hz while tuned to 29 hz, for example.

He’s now tuned at 30 hz he said, so he may not need a high damping factor, due to the tuning being fairly low, and most music not playing below there, so the box keeps control of the woofer plenty. Damping factor should matter less the higher up in frequency, due to the simple shortening in the waveform period (typically less xmax needed to reproduce).

 

[Buck 5,000+ posts]

Yea it only has lpf that I can see for the sub. It's Kenwood unit. The amp has crossovers, but last night they didnt seam to do much. It's the same layout as the picture that Bobby posted

What’s the db/octave slope on your amp? It should say somewhere close to the amp crossovers.

Does your head unit have a subsonic filter? If you have your crossover open wouldn't it be bottoming out hard on notes below your tuning?

No, my radio didn’t have a high pass/subsonic for the subs.

Yes, in general, but you have to play a decent bit under tuning, usually, to bottom out. The port is a resistor to air-energy at tuning frequency, so you have to play below (or well above, in some cases) that to lose the resistance-pressure buildup, and that loss in internal pressure is what makes a woofer bottom out. You’d probably have to play down in the mid 20’s before that happens, just depends on a lot of factors.