# Open back mod



## MkWolfire (Oct 14, 2016)

so today, ive played around with the back of my amplifier, i removed it put it back on, and I personally like the amp without the back panel, the problem is. How do i cut it because the control panel is supported with the back panel. Do i just cut everything except the place where the screws goes or to have a special shape or something. Amp is, again, a Vox VT20+ with a 8" speaker


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## greco (Jul 15, 2007)

Is this the back of your amp?










Depending on what is on the onside, you might be able to cut it about here...









However, you are going to ruin the tolex with the cut.

It might better to make a piece the same size as the top part (above the red line) from some plywood and use it after you remove the whole original panel and store it for later.

Can you post a pic of the amp with the back panel removed. Whatever is done must maintain the integrity of the structure of the cabinet and be electronically safe...for starters.


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## jbealsmusic (Feb 12, 2014)

greco said:


> Is this the back of your amp?
> 
> 
> 
> ...


A lot of the time, on amps like the one pictured above, the back panel is just a black painted piece of material (wood, mdf, etc.) I'm pretty sure the back panel on the one in the picture is not tolexed. You just have to re-paint the edge where you cut it and you should be fine.

If you cut it nice and straight and add a piece of foam or something across where you cut it (or another strip of wood in behind), you can turn it into a removable panel for a convertible back.


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## greco (Jul 15, 2007)

jbealsmusic said:


> A lot of the time, on amps like the one pictured above, the back panel is just a black painted piece of material (wood, mdf, etc.) I'm pretty sure the back panel on the one in the picture is not tolexed. You just have to re-paint the edge where you cut it and you should be fine.
> 
> If you cut it nice and straight and add a piece of foam or something across where you cut it (or another strip of wood in behind), you can turn it into a removable panel for a convertible back.


Now that I look at the pic more closely, I can see what you are describing and suggesting. Again, my age is showing...LOL


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## jbealsmusic (Feb 12, 2014)

greco said:


> Now that I look at the pic more closely, I can see what you are describing and suggesting. Again, my age is showing...LOL


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## BGood (Feb 20, 2015)

Funny that you'd find that better. I have a AD30VT with a 10" in it, and I find the closed back has better low frequency tone.

If you are not going anywhere with the amp, you could just leave the back off and install a plank across the bottom of the chassis, to hold it in place.. Because if you start cutting things up, the day you want to sell it, you won't have anything for it.

If you still want to do it, I start by cutting the Tolex as in the image (white). Then cut the panel all around (red) and wrap the Tolex back on the exposed edges, tack it from the inside or glue it.
How'S that for OPEN BACK 101 ?








​EDIT: Ooops, took my time writing my reply, didn't see the above suggestions by Greco and jbealsmusic.


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## Guest (Apr 28, 2017)

greco said:


> It might better to make a piece the same size as the top part (above the red line) from some plywood and use it after you remove the whole original panel and store it for later.


or something like this?


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## greco (Jul 15, 2007)

laristotle said:


> or something like this?
> 
> View attachment 83177


Probably even better and looks easier to do!


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## MkWolfire (Oct 14, 2016)

laristotle said:


> or something like this?
> 
> View attachment 83177


The thing is that i am a bit afraid with the lower integrity of the control panel


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## MkWolfire (Oct 14, 2016)

BGood said:


> Funny that you'd find that better. I have a AD30VT with a 10" in it, and I find the closed back has better low frequency tone.
> 
> If you are not going anywhere with the amp, you could just leave the back off and install a plank across the bottom of the chassis, to hold it in place.. Because if you start cutting things up, the day you want to sell it, you won't have anything for it.
> 
> ...


There is no tolex, its just painted


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## greco (Jul 15, 2007)

MkWolfire said:


> The thing is that i am a bit afraid with the lower integrity of the control panel


Put another pice of wood across that lower area which has good solid joints with the vertical wooden pieces at each side/end.


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## cboutilier (Jan 12, 2016)

If you're concerned about resale, go get a piece of plywood or MDF and cut out a new back panel. If you don't care about resale, get out the jig saw or recip saw and have fun. I've hacked up vintage cabinets, so you don't have to feel too bad.


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## MkWolfire (Oct 14, 2016)

cboutilier said:


> If you're concerned about resale, go get a piece of plywood or MDF and cut out a new back panel. If you don't care about resale, get out the jig saw or recip saw and have fun. I've hacked up vintage cabinets, so you don't have to feel too bad.[/QUOTEmy father got lots of piecesmof wood so im will make another back panel


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## Jimmy_D (Jul 4, 2009)

greco said:


> Put another pice of wood across that lower area which has good solid joints with the vertical wooden pieces at each side/end.


Sounds like the right plan to keep things in place.

PS - Greco - that's me raising your hand.


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## greco (Jul 15, 2007)

Jimmy_D said:


> PS - Greco - that's me raising your hand.


Thanks for letting me know....You can stop anytime now as I need to get my hand back down.


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## knight_yyz (Mar 14, 2015)

You could do something like the marshall Class 5. Its just two small boards across the back for stability. Although mine does not have the mesh piece. Must be a later development


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## MkWolfire (Oct 14, 2016)

BGood said:


> Funny that you'd find that better. I have a AD30VT with a 10" in it, and I find the closed back has better low frequency tone.
> 
> If you are not going anywhere with the amp, you could just leave the back off and install a plank across the bottom of the chassis, to hold it in place.. Because if you start cutting things up, the day you want to sell it, you won't have anything for it.
> 
> ...


I think i will make another panel but with a hole of this size. Thanks


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