The Amp Garage

Anyone try a Dumble style oval hole replacement back panel on their Deluxe Reverb? I wonder if it would improve bass response?
I'm so spoiled by my 2x12" D-style cabinet. It would be great to get the same type response from my combo. Sometimes, I just don't wanna bring all that stuff and my DR is my only combo amp.
Just wonderin' before I waste a Saturday and a piece of wood...
D

The tubes need proper ventilation on a combo, the oval hole would need to be as big as the original opening.

I think as long as you maintain the same gap below the chassis the ventilation will be fine. The oval cut-out will still have many times that area.

I wondering if you implemented this in the end and how much did the sound change/improve

I haven't tried with a tube amp yet, but I have had good luck with SS amps, really more noticeable bottom!

I'll bet it does have bass! That is close to a closed cabinet. Don't try that with a tube amp. It will need the upper gap to breathe. Otherwise it might be a fire hazard.

Resurrecting an ancient thread with some fresh content. I recently threw together (rather crudely, I willingly admit) an oval ported back panel for my 1979 Fender Deluxe Reverb. Using this cabinet has always been a struggle, particularly in getting a decent bass response that wasn't so diffused. The baffle is also the dreaded dado'd MDF panel, which certainly doesn't help. It had the two small rectangle composite (I think they are 1/4" MDF) panels on the back and it never had decent bass response with any speaker I tried in it or any amp I played through it. Bass controls basically didn't do anything. It may as well have a board with a speaker mounted to it.

The port I selected is 5 1/2" by 11 1/2" as per Tone Tubby's 1 x 12" cabinet port. The oval itself is not centered in relation to the center of the baffle just as the speaker isn't centered, but the port is directly centered behind the speaker. This port shape and size is also very similar to a Kay Model 703 combo amp I own that has ridiculous bass response for its size. I have a hunch that HAD may have lifted the oval design from the Kay amps, as many of their early 60's cabinets have this port design on the back panel. I might make a panel with a larger Dumble sized port in the future, but the current smaller port seems to improve the low end response to my tastes. It doesn't turn the cabinet into a 2 x 12" but it does add significantly to the sub lows without getting mushy. Single notes are much fatter because they have more bass-it sounds like its around 40-50hz or so. Very, very low and just a touch more bass, but just enough to give power chords some meat and single notes some good width. Palm muting and quiet to loud dynamics were also drastically improved. Definitely worth $15 and an hour of time. Some filing and some Tolex and it might actually be passable as a "public" amp.

Thanks y'all!

Ps. Apologies for the caveman woodworking. To be fair, I never said I was a pro.

I have no science to quote, but I have been making the ovals the length of the speaker and 1/4 the width, it seems to work!