Rumble 25 amp OK for 10 in speaker swap?

[wiscoaster]

I'm thinking of aquiring a used Fender Rumble 25 v3 bass amp to gift to a youngster as a bass practice amp. I have a 10 inch bass speaker sitting around gathering dust that came out of my Fender Rumble 40 when I swapped in a Celestion. The Rumble 25 cabinet looks big enough to take a 10 inch speaker in place of its original 8 inch. If the cabinet construction is similar, the front grille is just a pull-off panel and the speaker is front mounted, so I'd just have to enlarge the cutout and drill new mounting holes. The main unknown is whether there's enough room behind the front panel for the larger speaker. So, if anybody here has actually done this swap, please advise. Thanks!!

 

[iagtrplyr]

I'm thinking of aquiring a used Fender Rumble 25 v3 bass amp to gift to a youngster as a bass practice amp. I have a 10 inch bass speaker sitting around gathering dust that came out of my Fender Rumble 40 when I swapped in a Celestion. The Rumble 25 cabinet looks big enough to take a 10 inch speaker in place of its original 8 inch. If the cabinet construction is similar, the front grille is just a pull-off panel and the speaker is front mounted, so I'd just have to enlarge the cutout and drill new mounting holes. The main unknown is whether there's enough room behind the front panel for the larger speaker. So, if anybody here has actually done this swap, please advise. Thanks!!

Pose your question to the Fender Rumble Club where I believe this topic has been discussed before, and if it has, they’ll have a Wiki page all about it.

 

[abarson]

The cabinet is designed for the 8" speaker, not a 10", and most likely won't sound right as the interior dimensions will be too small. The Rumble 40 is designed for a 10" speaker and is a full inch larger in each direction.
I say leave it alone and gift it as-is.

 

[wiscoaster]

The cabinet is designed for the 8" speaker, not a 10", and most likely won't sound right as the interior dimensions will be too small.

Well, the Rumble 25 doesn't "sound right" as-is ... matter of fact it sounds pretty crappy. My thought is to make it sound "better". The Rumble 40 is only one inch larger in each dimension. But, I'll check out the advice given above about the Rumble Club. And in any case it might be fun as a "project" and if it doesn't work out, not much to lose.

 

[Ianf180]

Well, the Rumble 25 doesn't "sound right" as-is ... matter of fact it sounds pretty crappy. My thought is to make it sound "better". The Rumble 40 is only one inch larger in each dimension. But, I'll check out the advice given above about the Rumble Club. And in any case it might be fun as a "project" and if it doesn't work out, not much to lose.

I know this is an old post, but did you actually go ahead and fit the bigger speaker ?

 

[wiscoaster]

I know this is an old post, but did you actually go ahead and fit the bigger speaker ?

Yes, it fits in the case, with adequate clearance. You have to cut a larger diameter speaker cutout, of course, and relocate a couple of screw holes. All this can be done from the front without opening the case. All that being said, there are plenty of used Rumble 40's around for el cheapo prices, probably in the same ball park as you'd pay for a decent 10 in. speaker. And it's a much better amp. IMO, upgrading a Rumble 25 by swapping out the speaker is mostly an exercise in "can it be done?"

 

[agedhorse]

Yes, it fits in the case, with adequate clearance. You have to cut a larger diameter speaker cutout, of course, and relocate a couple of screw holes. All this can be done from the front without opening the case. All that being said, there are plenty of used Rumble 40's around for el cheapo prices, probably in the same ball park as you'd pay for a decent 10 in. speaker. And it's a much better amp. IMO, upgrading a Rumble 25 by swapping out the speaker is mostly an exercise in "can it be done?"

Agreed.

 

[micguy]

I'd bet that neither amp is really optimized acoustically (they're almost always too small to really do the speaker justice), but putting the 10" in the amp that had the 8" will drive it further from being optimized.

 

[agedhorse]

I'd bet that neither amp is really optimized acoustically (they're almost always too small to really do the speaker justice), but putting the 10" in the amp that had the 8" will drive it further from being optimized.

For what they are, they are actually fairly well engineered.

 

[MarkA]

Yes, it fits in the case, with adequate clearance. You have to cut a larger diameter speaker cutout, of course, and relocate a couple of screw holes. All this can be done from the front without opening the case. All that being said, there are plenty of used Rumble 40's around for el cheapo prices, probably in the same ball park as you'd pay for a decent 10 in. speaker. And it's a much better amp. IMO, upgrading a Rumble 25 by swapping out the speaker is mostly an exercise in "can it be done?"

Since you did it (and, presumably, made a gift of it to the kid you mentioned), though, I am curious as to what changes in sound and performance (Did it fart-out early? Was there a noticeable difference in low-end support with the smaller box?) that you observed. I am fairly familiar with both the Rumble 25 and Rumble 40, if you want to use them as points of reference.

Note: I am not planning to repeat this experiment, just curious.

While I'm at it, I'm curious about the effects of your Rumble 40 speaker swap -- have you documented those elsewhere?

 

[wiscoaster]

Since you did it ... I am curious as to what changes in sound and performance (Did it fart-out early? Was there a noticeable difference in low-end support with the smaller box?) that you observed. I am fairly familiar with both the Rumble 25 and Rumble 40, if you want to use them as points of reference....

It was some time ago that I did it, and don't remember specifics, other than it sounded "better". I still have it in storage, so I might take it out sometime and re-evaluate it with a better test. Though, frankly, I think cutting a bigger hole for the 10 inch speaker in the frame probably adversely affects its acoustics by weakening the speaker frame mounting. It's got to have a certain rigidity. Bigger speaker, less rigid: sounds like trouble. But I can't document that other than through trial and error, and I've got too many other higher priority projects going on right now.

....While I'm at it, I'm curious about the effects of your Rumble 40 speaker swap -- have you documented those elsewhere?

Again, some time ago, I don't remember if I documented it (you can search on my screen name, I suppose), but I do remember that, again, it sounded "better".

The biggest improvement that I can document was the Rumble 25 speaker that went into the Rumble 15. I sold that little amp to my local GC recently, and I asked the salesperson who was testing it for acceptance about its sound, and he said he'd never heard a Rumble 15 that sounded that good.

 

[MarkA]

It was some time ago that I did it, and don't remember specifics, other than it sounded "better". I still have it in storage, so I might take it out sometime and re-evaluate it. Frankly, I think cutting a bigger hole for the 10 inch speaker probably adversely affects its acoustics by weakening the speaker frame mounting. But I can't document that other than trial and error and I've got too many other higher priority projects right now.


Again, some time ago, I don't remember if I documented it (you can search on my screen name, I suppose), but I do remember that, again, it sounded "better".

The biggest improvement that I can document was the Rumble 25 speaker that went into the Rumble 15. I sold that little amp to my local GC recently, and I asked the salesperson who was testing it for acceptance about its sound, and he said he'd never heard a Rumble 15 that sounded that good.

Somewhere, some kid is rocking the ultimate Rumble 15 and doesn't know how good he's got it. ;-)

Thanks for the perspective!

 

[wiscoaster]

Sorry, I edited while you posted.

 

[MarkA]

Sorry, I edited while you posted.

No worries -- appreciate both the answer and your conscientiousness!