Picked up an old bass cab, but it rattles like crazy!

[thebigcheese]

Thanks to the wonderful people on these forums, I picked up a refurb Acoustic B200H head for $180. Looking to save even more money, I went on Craig's List to sit what I could scrounge up for a cab. I found a Laney bass cab for $60. It's an older one that is clearly worn and, unfortunately, doesn't have any of the info about what it's capable of handling (I mean that literally; the back of the speaker is all black), but it seems to handle the B200H fine, so that's that. It's a pretty good sounding cab, actually, but it sure does rattle a lot. Most of the rattle comes from the back panel, so I thought I'd take that off just to see if there's rattle from anywhere else. There definitely is. The grill seems to be attached with some foam, so that shouldn't be rattling too much (and pressing against it doesn't seem to stop any rattling), so it seems like the rattling is mostly coming from where the wood panels are joined together. Is there anything I can do about that? I was thinking about putting some Dynamat between the speaker and where it attaches, or between the back panel and the rest, but I'm wondering if that would actually do anything since the whole point of a cab is to vibrate and enhance the bass response. What are my options here?

 

[ggunn]

Thanks to the wonderful people on these forums, I picked up a refurb Acoustic B200H head for $180. Looking to save even more money, I went on Craig's List to sit what I could scrounge up for a cab. I found a Laney bass cab for $60. It's an older one that is clearly worn and, unfortunately, doesn't have any of the info about what it's capable of handling (I mean that literally; the back of the speaker is all black), but it seems to handle the B200H fine, so that's that. It's a pretty good sounding cab, actually, but it sure does rattle a lot. Most of the rattle comes from the back panel, so I thought I'd take that off just to see if there's rattle from anywhere else. There definitely is. The grill seems to be attached with some foam, so that shouldn't be rattling too much (and pressing against it doesn't seem to stop any rattling), so it seems like the rattling is mostly coming from where the wood panels are joined together. Is there anything I can do about that? I was thinking about putting some Dynamat between the speaker and where it attaches, or between the back panel and the rest, but I'm wondering if that would actually do anything since the whole point of a cab is to vibrate and enhance the bass response. What are my options here?

The point of the cab is to contain the air volume behind the speaker and use it to support the speaker cone in various pleasing ways. Nothing in the cab should rattle or vibrate. Take it apart and use wood glue wherever there are panels that touch but are not secured tightly against each other. Make sure all the screws are tight and the holes not stripped. Use toothpicks in any stripped holes until the screws are tight.

 

[thebigcheese]

The point of the cab is to contain the air volume behind the speaker and use it to support the speaker cone in various pleasing ways. Nothing in the cab should rattle or vibrate. Take it apart and use wood glue wherever there are panels that touch but are not secured tightly against each other. Make sure all the screws are tight and the holes not stripped. Use toothpicks in any stripped holes until the screws are tight.

You mean take the whole thing apart? What about the tolex or whatever it's called?

 

[ggunn]

You mean take the whole thing apart? What about the tolex or whatever it's called?

There's probably no reason to do that unless the corners have come apart. Actually, the first thing I'd do is open up the back and check any internal structures. If that stuff is screwed together, tighten the screws. If it's glued, check for broken glue joints and reglue if necessary. When you put the back back on, look for loose, stripped, and/or missing screws. Tighten everything down.

 

[dementedchord]

i've seen where guys have sprayed the inside with like car undercoating and iy did wonders for the cab... where normal screw tighting didn't work...

 

[dervish riff]

Depending on how the cabinet's laid out, you could place a couple or more 2x4 "soundposts" between the baffle board and the back to stiffen the cabinet.

If all else fails, make the cab front loading and seal up the whole thing.

 

[thebigcheese]

It's already front loading, actually, though you have to take off the back to fix the jacks if you need to. Tightening the screws down has helped a lot. There were only 4 holding the back on, despite there being more like 8 holes, so I added a couple to keep it tight. At louder volumes it might still rattle, but at my practice volume it's nice and quiet. The screws are kind of old and rusty and a couple of the holes are stripped out, so if need be, I can always put new screws in.

 

[notCardio]

How's that Acoustic head working out? I've thought about getting one just for old time's sake. Used to have one of the originals back in the day.

 

[thebigcheese]

How's that Acoustic head working out? I've thought about getting one just for old time's sake. Used to have one of the originals back in the day.

I love it. I tried all the fancy expensive ones at GC before I settled on it. I'm still shocked that it's possible to have such a good amp for so cheap. The Laney cab is actually pretty good, too, so I'm not sure I could beat the cost/performance balance I hit. I think the B200H restocks are still on clearance at MF, so check that out if you're looking for one.

 

[ggunn]

It's already front loading, actually, though you have to take off the back to fix the jacks if you need to. Tightening the screws down has helped a lot. There were only 4 holding the back on, despite there being more like 8 holes, so I added a couple to keep it tight. At louder volumes it might still rattle, but at my practice volume it's nice and quiet. The screws are kind of old and rusty and a couple of the holes are stripped out, so if need be, I can always put new screws in.

There's your problem right there and it's easily remedied. Make sure that every screw hole is tightly occupied and that none of them is stripped out. If some are stripped, use the toothpick trick that we use to secure stripped strap button screws.

 

[Farview]

All you have to do is take off the back and get some of that foam weather stripping (the 1/2 inch wide stuff with the adhesive back) and put that on the lip that the back screws into. If there is a center post, put the foam on that too and sink a screw into it.

If the screws won't tighten because the wood is stripped, put some wood glue in the holes and put the screws in.

 

[thebigcheese]

I discovered today that if I turn it up past the practice volume at all, it still rattles. It sounds almost like it's going to fall apart at higher volumes and the amp head starts sliding around. The grill had some of that foam stuff behind it, but it's so old it's hardly useful anymore. I have some of that no-slip mat stuff that you can buy for your car, so I might put some of that in there. The back can just use Dynamat (or some of the foam stuff, but I'd have to actually go buy some of that), since it's not visible. As for the rest... well, I'm thinking that even if it's not screwed together, I'm going to get some wood screws and screw it all together anyway just to make sure it's all nice and tight together. I was thinking I might just grab some slightly wider screws for the holes that are stripped. Not sure what to do about the amp sliding... I guess I can just put it on the floor or something for now, though the cable I just cut for it probably won't reach. What a pain. I guess that's what I get for only $60, huh? It'll sound nice when I get it all together nice and tight, though.

 

[RejectionNinja]

For the holes that are stripped, here is the solution:

1. Get some super glue and a bunch of tooth picks.
2. Put super glue on a tooth pick and stick it in the hole.
3. Break off the tooth pick at the top edge of the hole.
4. Repeat steps 2-3 until the hole is all packed up with super glued toothpicks.
5. Put the original screw back in.

You can probably skip the super glue if you wanted, or use a small wooden dowel instead of tooth picks if you want to be fancy.

 

[thebigcheese]

I just used different screws, and that seems to have worked for most of them. I used the weather strips for the back, so I don't think that's rattling now, but I think the speaker itself may be rattling. You know how it has the foam running around the edge? I think it might be that. I had that problem with a car speaker once, but it would eventually get held down by a cover, so it didn't matter. I guess I could buy a 15" cover if that really is the problem, though I might have to drill some new holes to put it in that way (right now it's held in place by metal tabs that push against the metal part of the speaker).

You know, I plugged my Blues Jr. into the cab today just to see how that would work. I'm kind of annoyed that I spent all that money on the Cannabis Rex for the Blues Jr. now. I guess it will still be nice when I don't want to drag the cab around, but at home, I don't think I'm ever going to use the Blues Jr.'s speaker again. The sound is so much fuller with a big cab.

 

[dementedchord]

How's that Acoustic head working out? I've thought about getting one just for old time's sake. Used to have one of the originals back in the day.

my bassist bought one 2 weks ago... and he loves the little thing... runs it into an old hornloaded Sunn cab...

 

[thebigcheese]

You know, it may actually be the speaker itself. Not rattling like I thought it was, but more like... not handling the amp. If I turn it up to a more appropriate rehearsal volume, it starts to distort some. That's a shame. It still works great for guitar and lower volumes. I guess this just means I'll have to replace it eventually. Which I was probably going to do anyway with an Acoustic 4x10.