Amp distorting out on low B

Cougmeister · #1 12-16-2012, 05:33 PM

I have an Acoustic B450 combo amp and any time I use one of my fivers (a fender jazz and schecter stiletto extreme) the amp distorting out on the low B when bringing it up to match an open and loud drum kit. It almost sounds like its busted, but only on the B string. All others sound wonderful. Any idea as to what is causing this?

B-string · #2 12-16-2012, 05:40 PM

Speaker unloading at lower frequencies. Try cutting the bass with the 5 strings.
You could also try covering or stuffing the port if it has one.

Downunderwonder · #3 12-16-2012, 05:56 PM

Your speaker can't make low B fundamental. Maybe it also can't handle 60hz either. I can get some 60hz out of my Trace 1518 but not a heap. Lucky for me I have 12 band graphic.

What EQ do you have?

The f-deck HPF is made for this issue.

scottfeldstein · #4 12-16-2012, 06:45 PM

A 210 isn't enough speakers to keep up with a loud drummer.

Cougmeister · #5 12-17-2012, 08:55 AM

Quote:

Originally Posted by Downunderwonder

Your speaker can't make low B fundamental. Maybe it also can't handle 60hz either. I can get some 60hz out of my Trace 1518 but not a heap. Lucky for me I have 12 band graphic.

What EQ do you have?

The f-deck HPF is made for this issue.

It has a 6 band eq (knobs) with a notch filter and horn on/off switch. Short of buying a new amp, are there any remedies to fix this? I love my fivers too, so I don't want to cut them out of the picture.

scottfeldstein · #6 12-17-2012, 09:09 AM

I'd say turn the lowest frequency down to 9 o'clock. Then bump the middle two up to about 2 o'clock. Run the rest at noon. You'll probably cut through the band like a hot knife through a very soft thing and might not have to turn up as loud in the first place.

As far as the notch filter, just shut it off.

Cougmeister · #7 12-17-2012, 09:47 AM

Any opinions on the horn? I can't seem to hear a difference.

scottfeldstein · #8 12-17-2012, 09:49 AM

It should just add some crispiness and string noise. And probably some hiss. I run the horns on my cabs at about 1/4. YMMV. It won't affect your problem either way.

Downunderwonder · #9 12-17-2012, 01:50 PM

If you can't hear the horn your hearing is stuffed or it's not working.

TB member fdeck sells a gizmo which cuts off lows where you choose, leaving you free to eq the rest how you like it. It's cheap enough.

If there is a matching 2x10 extension cab for your amp that'll fill out the sound.

BassmanPaul · #10 12-17-2012, 01:52 PM

Quote:

Originally Posted by scottfeldstein

A 210 isn't enough speakers to keep up with a loud drummer.

+1 I agree fully. A pair of identical 2x10s makes a great rig.

scottfeldstein · #11 12-17-2012, 01:56 PM

Wow, according to the manual, it can run external cab

"Two-conductor, 1/4” Speaker Output Jacks, 2 Ohms minimum load, parallel. The B450 operates at 450 watts with the internal speakers, and a full 600 watts with
an additional speaker (4 ohm minimum)."

Pick up one of these! Problem solved!

http://www.guitarcenter.com/Acoustic...20-i1506177.gc

Cougmeister · #12 12-17-2012, 04:03 PM

Would it be better to go for the single 15 cab to go with it instead?

Munjibunga · #13 12-17-2012, 04:10 PM

Quote:

Originally Posted by Cougmeister

Would it be better to go for the single 15 cab to go with it instead?

No. Another 210.

Cougmeister · #14 12-17-2012, 04:16 PM

Well I think I'm just going to have to play around with it, cause I don't have any money to drop on another cab atm. Hopefully one of the previously mentioned methods will work. Tomorrow ill try to take a pic of the eq with the settings right before the sound gets flappy.

Cougmeister · #15 12-19-2012, 05:30 PM

Do you all think that a 1x10 cab (4 ohm) would be much help? I just separated an old combo amp and could hook that cab up to it. Btw, couldn't get a pic of the eq. My practice space is much too small to have it turned up very loud. I typically run with it pretty flat though and use the bass eq

scottfeldstein · #16 12-19-2012, 05:33 PM

It would help a small amount. But you'll be running a high risk of blowing it.

Downunderwonder · #17 12-19-2012, 05:56 PM

https://docs.google.com/viewer?a=v&q...p2vH5TIzw76Mgg

I'd try using the notch filter set to fully anitclockwise 50Hz and see what that does. There may be enough of a gap to the lowest EQ fliter that you can leave it flat and boost the one labled 120.

The 1x10 probably doesn't take much power. If so it would hinder more than help because you'd fart it out before your main cab reaches power.

This is what you need for the meantime, never fart out another cab again, best $55 you'll ever spend:

https://sites.google.com/site/hpftec...web-order-form

Cougmeister · #18 12-19-2012, 06:12 PM

The combo was a Peavey Max 110, if that helps any with that. I plugged it up and I'm getting a clean sound out of it so far. I may have a gig next friday, so I guess that would be the true test for it. How can I find out how much the speaker is rated for?

Downunderwonder · #19 12-19-2012, 06:23 PM

Can you pick it up with one finger? Not much power.

Google will have a better answer for you but it won't tell you how badly matched a single cab is matched to a double loaded cab of the same impedance. It will be trying to make the same amount of power as the combo cab itself, so you can only turn up half as loud, result: very little extra volume.