Marshall 1960B Mod?

[TremoJem]

I have a Marshall 1960B.

It has the four 75W Celestians and is rated at 300W, I think, as I have not used it or looked at it in years because a friend has it in his studio and I have read posts about how they are not that great for Rectos. But now my friend needs the space and so I am going to pick it up.

You can run it in mono or stereo.

Here is the mod that I would like to do and would like some feedback on.

It is my intention to use this in stereo and connect each of my two Tremoverbs to it, one on each side respectively.

In and effort to get a tighter and better sound (maybe some punchier low end), I thought of isolating the left and right side from each other.

My question is this. If I used 3/4" plywood to insert (permanently affixed of course) between the speaker sets on the left and right side of the cabinet would this yield a good sound.

This would be like having two vertical 2x12s in one speaker enclosure. I would not change anything about the cabinet. I would just add this separator to isolate each side of the cabinet and then acoustically seal each side. I guess I would use a very small amount of sealant in all the seams and then add some insulation to each side. This would then be two side by side vertical 2x12s.

But, would this sound good?

Please help and don't be afraid to tell me what you really think this will achieve.

I am not a speaker engineer and would really appreciate your help, thanks.

 

[snave]

I imagine the cab may become more directional, and it will change the bass response. Whether it will feel tighter is anyone's guess.

For what it's worth, the Roadking 4x12 has a somewhat similar design, except one side is open-back and the other is closed.

 

[TremoJem]

Interestingly my home theater sub woofer is a very small ported cab that has a ten inch speaker.

It is capable of efficiently reaching 20Hz.

Obviously this design is very specific and restrictive to it's application.

But, I have to say that it lends itself to the notion that if I was to baffle the cabinet in half that I might be able to produce a tighter, more percussive response.

 

[elvis]

Whether it sounds "good" or not is in the ear of the beholder. For sure it will sound "different". The acoustic volume will be cut in half, changing the resonant frequency.

If you haven't tried the amps into the unmodified cabinet, you should do it before modifying. One thing is for sure, you can always return the cab to stock after you modify it (minus any cosmetic changes).

You could do a test run with a tight-fit center baffle that is not fixed in place except by friction. If it's wedged in there pretty well, it should sound quite similar to the final modification.

 

[TremoJem]

I agree that there is nothing in front of me that says this would improve sound or performance.

I like the idea of simulation first.

Thanks