Cab gurus (closed back question)

[bufbills]

I have a lopo 212 closed back. Sounds great. My question is, if I remove the large recessed side handles, would that give me an fairly accurate representation of what it would sound like if i converted it to an open back. I plan on trying removing them later to see how it sounds. My thought is that if it spreads out the sound more I could just leave the handles out instead of altering such a nice cabinet.

Thanks for your thoughts!

[b-squared]

I don't think it would be the same as even a partial open-back, but it is an interesting idea.

It would bounce some sound out for a more 3D sound, but I'm not sure it would make a difference overall, as the sound would never make it out to the audience (or you).

The open back is supposed to bounce off the floor/back wall to get back out front, as I understand it.

Any decent woodworker could take the back panel and cut it into 3 pieces...that way you could remove 1 or 2 of the panels to get that sound when needed.

BB

[bufbills]

Originally Posted by b-squared

I don't think it would be the same as even a partial open-back, but it is an interesting idea.

It would bounce some sound out for a more 3D sound, but I'm not sure it would make a difference overall, as the sound would never make it out to the audience (or you).

The open back is supposed to bounce off the floor/back wall to get back out front, as I understand it.

Any decent woodworker could take the back panel and cut it into 3 pieces...that way you could remove 1 or 2 of the panels to get that sound when needed.

BB

I wonder if the drummer would benefit. I could easily handle the woodwork(20 plus years in woodworking) Ill toss that around for a while. If i were to do two panel mod, if the base became too loose, I could always just remove one panel.

[b-squared]

I think most would remove the middle panel, and leave the other two. With no panel that cab should be pretty sturdy.

If the cab was lined up right the drummer might hear it, but that's a pretty small opening...the 'beam' would be pretty tight.

Putting a mic there might give you a different tone to mix with a mic on the front of the speaker, though.

BB

[bufbills]

Gotcha. I guess it couldnt hurt to convert the cab. It would certainly be versatile, making it like having two cabs with identical speakers.

[moodyedge]

be better from the drummer if the amp was futher back and the kit a little futher forward. Ive always wondered what the drummer can actually hear when playing...Probably loud mud from bass guitar, a muffled racket from a guitar cab and a mumbled voice from a singer shouting at the front...It cant sound that good...Probably the best place to be is the guitarist because you get everything if your near the vocal monitor......balance wise that is......Must be good being the singer being able to listen to the band play. I wish I could watch my band play at a gig live rather than be distracted playing guitar parts.


Anyway..........Maybe the sound pressure has more of a direct affect on the back panels due to the movement of the speakers back and forward so as mentioned taking off a rear panel would change things more than the sides would. If anything you would probably lose a little bottom end punch but Im no audio expert. I can understand the idea of taking handles off......just throw them out and see what happens.


It's easily made into a two panel back...two small batterns glued in and chop the panel in half..

Ive got two removeable panels on the back of this matamp cab...Ive tried it with them off....didnt really notice anything I liked about it afterwards so they went back on. I might take one off to record the guitar parts just to try for a different sound...

What are you trying to gain by doing this?

[SteveGangi]

As was already said, make it a convertible so you can have a choice, whenever you want. Remember it is not just the size of the opening, it is also the distance. Think of the sound waves as exactly that - a wave. The wave coming around from the back will interact with the wave coming from the front. It will cancel and reinforce various frequencies (not completely but enough to color the sound).

In fact, Lopo cabs are often the same exact dimensions, between the closed, open, and convert cabs.

[Dolebludger]

I'm not an expert on open vs closed back cabs, but I have a friend who is. He says open back cabs spread the sound around more (both on stage and in the venue) while closed back are better for projection of your sound in large venues. So it depends on where you play.

[singlecut]

i can say that i have 2 cabs that are convertable. 2x10 and 1x12
both sound way better open.

[aneas fool]

Originally Posted by singlecut

i can say that i have 2 cabs that are convertable. 2x10 and 1x12
both sound way better open.

I have built lots of cabs ....some speakers work better in sealed cabs and sealed ported cabs and others like to be open back ....open back seems to have more air about them...sealed have more snap in the mids...ported tuned cabs have a better lower bass sound and are more efficient in the lower register.....all guitar speakers will work in any one of the three ways....it comes down to what you prefer in sound .....a cab can be made to be convertible to do all three with a little alteration....put a plug in the port for sealed....and have a drop down hinged panel for open back...to be sure when it is sealed you need a foam gasket on the drop down panel

[Dolebludger]

Singlecut:

I have two 1X12s -- one open and one closed.For larger venues (or God forbid outside) I take them both. For small venues, I take only the open back. Cabs and speakers are identical. But the open back just sounds "prettier". That is, until I need to really project my tone, and then I really need the closed back also to allow me to keep my volume below eardrum bursting level and still project over the drummer.

[Sven]

I recently converted a closed back cab to an open back setup. I made new panels and kept the original one intact.....just in case. The cab sounds much better to me, with more clarity and openness. I have it as a horizontal three-piece with the center one omitted. For the situations I play in, I prefer the open back arrangement.