15 inch to 12 inch. Is it possible? Yes.. it is.

bacchanalian

I have far too much amp for my limited requirements and am thinking of downsizing the speaker from the standard 15 inch to a 12 inch.
The amp is a Victoria Regal combo that I run through an attenuator. The 15 inch produces more bass than my neighbours are comfortable with.

Is downsizing something that is easily done?
Is it a sensible thing to do?
Should I sell up and change to a Blues Cube Artist 112?

Let me have your thoughts

ICBM

You need to make a 'reducer' - a 15" diameter ring of plywood with a 12" speaker cut-out in it. Bolt it to the 12" speaker and fit it into the cabinet in place of the speaker.

Whether it will reduce the bass enough to keep the neighbours happy, I'm not sure. I know this sounds like I'm insulting your intelligence , but have you tried turning the bass down on the amp? If it's not already at zero then turning it down will probably make more difference than the speaker.

If you've tried that already and it's not enough, you could also try a 10" speaker instead of a 12" in the same way, which will reduce bass and volume further.

EricTheWeary

Other thought might be those Auralex risers? First they would stop some of the transfer of sound via the floor, second people tend to experience a cut in the bass ( as they decouple the cabinet from the floor - of the OPs combo is an upstairs room, for example, it's gaining bass from basically sitting on a giant drum). There are different ones but around £70.
On one of the reviews on Amazon I just noticed a 'stopped the neighbours downstairs' complaining comment.

Rocker

Before you buy, try a partially inflated motorcycle inner tube to lift the cabinet off the floor. The cab will wobble but you can determine if one of those acoustic isolators will work..

Sassafras

Rocker said:

Before you buy, try a partially inflated motorcycle inner tube to lift the cabinet off the floor. The cab will wobble but you can determine if one of those acoustic isolators will work..

Buying a motorcycle seems to be an expensive way round the problem.
  

EricTheWeary

Sassafras said:

Rocker said:

Before you buy, try a partially inflated motorcycle inner tube to lift the cabinet off the floor. The cab will wobble but you can determine if one of those acoustic isolators will work..

Buying a motorcycle seems to be an expensive way round the problem.
  

It might also convince the neighbours that the OP is in a scary biker gang and they'll stop complaining anyway. 

bacchanalian

ICBM said:

You need to make a 'reducer' - a 15" diameter ring of plywood with a 12" speaker cut-out in it. Bolt it to the 12" speaker and fit it into the cabinet in place of the speaker.

Whether it will reduce the bass enough to keep the neighbours happy, I'm not sure. I know this sounds like I'm insulting your intelligence , but have you tried turning the bass down on the amp? If it's not already at zero then turning it down will probably make more difference than the speaker.

If you've tried that already and it's not enough, you could also try a 10" speaker instead of a 12" in the same way, which will reduce bass and volume further.

I don't run it quite at zero but have it waaaay down and the treble at 11. 
 
A reducer sounds doable.  I had a quick look and the amp and cabinet appear to be straightforward to disassemble. Lots of screws, nuts and bolts. Once the current speaker mount was removed it could be used as a template for a new mount with 12/10 inch port. 
Hmmm ... I think the next step is to borrow a couple of friends 1x12 cabinet and Princeton and try running it through them.

What I am looking for is the same tone I have but just hitting my ears rather than spreading out so much.

Thank you for the tips

Dominic

buy some Acoustilay mat from Sound Reduction Systems -stand speaker on it -make a shield and stick some bass trap foam on it in front of the cab and adjust to your ear /season to taste

strtdv

Have you tried tilting the amp back?

Decoupling it from the floor will significantly reduce the bass going through to you neighbours.

ICBM

You don't need a fancy riser or an inner tube to test the basic idea of whether decoupling it from the floor would be enough - just put it on a large cushion.

bacchanalian said:

What I am looking for is the same tone I have but just hitting my ears rather than spreading out so much.

In that case, if you're going to try a smaller speaker then a 10" will probably sound more like the 15" than a 12". I can't remember the exact physics behind it, but there is a reason… it's also why bass amps traditionally more often use 10s and 15s than 12s.

bacchanalian

Thanks @ICBM. I like the idea of that. The regal takes any Octal valves and I have it running the same valves as a Princeton.
From that point of view a 10 inch sounds like a good match.

Thanks to everyone else.  I actually have it on two layers of Auralex foam already but like the idea of a tighter low end.

bacchanalian

Resurrecting this thread just to close it off and by way of thanks for the advice, particularly @ICBM, and the patience shown me by @RiftAmps.

 https://i.imgur.com/SNkHSps.jpg
Regal II with 15 inch Eminence.

https://i.imgur.com/kjp1G7G.jpg

This is what the back of a 15 inch Eminence looks like

https://i.imgur.com/T9O3jWf.jpg

I really hope this works out

https://i.imgur.com/0DIQSP4.jpg

After some discussion and advice @RiftAmps sent me this lovely new 12 inch baffle ready to take my new WGS G12C.

 https://i.imgur.com/1lj02oj.jpg

Success!

https://i.imgur.com/SNkHSps.jpg

Victoria with new 12 inch installed

The last picture is a joke at my expense as it is the same picture of the amp.  It may seem like quite a bit of hassle for 3 inches but the difference is already evident. I can turn the bass control up to 5 or even 6 without taking the plaster off the ceiling in the room below.  I don't want to overstate the improvement yet as I have only tried the new speaker for an hour but I think the tone is better. There seems to be more definition across the tonal range.  I would describe the 15 inch as nearly like a bass with guitar on top whereas the 12 inch is all guitar.  I know what I mean and I can't imagine a better amp for me (until the next time @RiftAmps posts, or there is a ToneKing/Carr/Lazy J in the classifieds).  
 

Telejester

phew I thought this was about having a penis reduction when i read the title

rlw

Telejester said:

phew I thought this was about having a penis reduction when i read the title

That would be more like changing a 1 x 12" to a 1 x 10" though