Modding a Rumble 25 combo..

[ThePoloHobo]

Welp, The speaker in my combo is blown, rattles a lot. Would it be possible to put in a larger speaker? I'm pretty sure a 10" could fit, there's a lot of extra room. I can use the Fender warranty, but I'd really like this thing to sound better, and this not happen again, as I'm sure the speaker in it is very cheap.

I just use this for bedroom practice and jam sessions with acoustic players, but some more low end would be nice!

What does TB think?

 

[ThePoloHobo]

Took the speaker out, no impedance listed..

 

[Linnin]

Took the speaker out, no impedance listed..

Owner's manual states 8 ohms.
[Invalid or Expired Link Removed]

 

[Anachronism]

It's not worth modifying unless you have a great deal on a speaker. If you've got a spare 10" lying around, or a buddy does and will sell it to you cheaply, sure, go ahead and mod. If not, you'd probably be better off using the warranty to repair this and saving up for a better small amp.

 

[ThePoloHobo]

yeah perhaps. Too bad I didn't get the pro coverage or I could just get my money back. But I'm probably still better off not ever buying it for anything.

 

[Linnin]

Would it be possible to put in a larger speaker? I'm pretty sure a 10" could fit, there's a lot of extra room

Are you capable of doing the work yourself? The box dimensions are almost the same as the Rumble 40 1x10 combo, so yes a 10" 8 ohm woofer will work. Again are you capable of retuning the cabinet? Also if you are going to go to all that expense, properly lining the box is an absolute must. A lot to think about.

 

[ThePoloHobo]

Yeah, that's why I asked, not entirely sure its a project I can do. I can cut a round hole, sure. I don't know anything about tubing cabs, lining, etc. Sigh.. Warranty repair it is.

 

[BassmanPaul]

Using the warranty makes the most sense to me.

 

[AstroSonic]

You need a driver with more excursion capability (Xmax). The Dayton PA255-8 will perform well in the Rumble 25's 0.8 cf cab, tuned between 50 and 60 Hz. For two 2-inch diameter ports, the length will range from about 4 to 6 inches. There will be low to moderate, mid to upper bass peaking - enough to add some bass richness, but not enough to cause soft, pillowy bass and poor note definition. You should install some acoustic lining, as Linnin suggested. This will add 4 to 5 lbs to the weight, but is still quite reasonable. Relative to the stock Rumble 25, you will get deeper, more articulate bass, smoother mids (due mainly to the acoustic lining), and higher volume (due to greater sensitivity of the Dayton driver).

 

[ThePoloHobo]

Interesting! That speaker is rather affordable.

 

[Slackerprince]

The subwoofer for my stereo system is Dayton Audio. It's nice.
I have a Warwick Blue Cab 30 with a 10" speaker. I can turn the volume all the way up with no issues.
It's nice to have a speaker in there that can handle all the juice.
If I were you, I'd put that Dayton in there, instead of a direct Fender replacement, which will result in more of the same.
Lining is relatively simple, and there should by some YouTube on it or threads in here to help you.

S

 

[BassBeginer64]

I also picked up a used Rumble 25 for a project practice amp , I was looking at up grading with a
Eminence Alpha-8A 8" PA Driver due to its lower F/R 58-5000 and its sens @94
the Dayton Audio PA2008-8" F/R 70-9000 and its sens 92, the difference is about 20 bucks in cost, but with a lower frequency response of 12 will be nice, need to find out what the OEM speaker F/R is.
My shop is right next door to a custom cabinet shop (not speakers) lol, I like the idea of popping a 10"speaker in it and being done, be a great under the end table practice amp and also acoustic lining it too.

 

[BogeyBass]

I'm sure the factory speaker isn't very special.
And there is a few higher grade speakers no problem.

Judging from factory specs on fenders 12" speakers. I'm sure even a cheapo alpha or beta 8 probably be considered a upgrade to the factory 8

Likewise alot of used 12" bass combos
That would perform better or the same

I don't know the volume of your cab
But a 10" that works well in small enclosures would be the ticket if going the 10" route

 

[BassBeginer64]

There really isn't any good 8" Bass Woofers out there with good F/R in the 40s and Sensitivity above 95, well not without going nuts on cost of $150 to $200 bucks, and I understand its a practice amp, that is why I was not too bothered at a $50 to $70 up grade speaker that wont blow out or wash out, but thinking even with the Rumble 25 ported that a 10" would be too big for that enclosure.
Here are a few 8" replacements I am looking at right now, your thoughts
BEYMA 8BFR - 8" LOW & MID SPEAKER

http://www.usspeaker.com/beyma 8BFR-1.htm

BEYMA CM-8B - 8" LOW & MID SPEAKER

http://www.usspeaker.com/beyma CM-8B-1.htm

EMINENCE ALPHA-8A - 8" SPEAKER

http://www.usspeaker.com/homepage.htm

Dayton Audio PA200-8 8" Pro Woofer Speaker

"Dayton Audio PA200-8 8" Pro Woofer Speaker" from www.parts-express.com!

FaitalPRO 8FE200 8" Professional Midbass 8 Ohm

"FaitalPRO 8FE200 8" Professional Midbass 8 Ohm" from www.parts-express.com!

 

[AstroSonic]

That's a good short list of potentially suitable drivers. The Faital and Dayton have the strongest and deepest bass response (ported), and both have smooth mids and highs. The Faital is a little more sensitive. The bass in the Alpha is nearly as good (ported). The alpha is the most sensitive of the group, and has somewhat elevated upper mids and lower highs - this provides presence that many players prefer. The Alpha seems well voiced for bass guitar. If you would prefer a sealed cab, the Beyma 8BFR is well suited.

If you are looking for a more hifi tone: choose the Faital or Dayton.

For a sealed cab tone: the Beyma 8BFR.

For a classic full range bass guitar tone: the Alpha.

Fpr the loudest: the Alpha.

 

[BassBeginer64]

Yeah its pretty tough to pick one, again I know a lot other people are looking to upgrading this lil combo amp, I have upgraded a few amps and the Eminence brand stands out, I seen the Alpha at $50 bucks through amazon, the Dayton just does not have the F/R I am looking for. Yeah think ill go with the Alpha 8 PA
https://www.amazon.com/gp/product/B000AAPNKM/ref=ask_ql_qh_dp_hza

 

[Hubtone]

I know this is an older post but I was searching for speaker upgrades for Rumble 25 which led me to this post. I'm a tinkerer at best, don't know anything about cab size vs. speaker size, ported vs sealed, xmax, cab tuning, etc but I can put a speaker in. I took a chance and went with the Alpha 8A. It didn't sound good at all. It moves a LOT of air out of the port. So much you can hear it. It sounds like when you purse your lips and blow hard. And it's loud. I don't think that's a good speaker for this cab unless I'm doing something wrong. Has anyone tried the Dayton or Alpha 8A with different results? I may try the Dayton...

 

[BassBeginer64]

I did the Alpha 8-A, had no issues for a practice mobile amp.
Did you check the ohms?

 

[pie_man_25]

I know this is an older post but I was searching for speaker upgrades for Rumble 25 which led me to this post. I'm a tinkerer at best, don't know anything about cab size vs. speaker size, ported vs sealed, xmax, cab tuning, etc but I can put a speaker in. I took a chance and went with the Alpha 8A. It didn't sound good at all. It moves a LOT of air out of the port. So much you can hear it. It sounds like when you purse your lips and blow hard. And it's loud. I don't think that's a good speaker for this cab unless I'm doing something wrong. Has anyone tried the Dayton or Alpha 8A with different results? I may try the Dayton...

That's port chuffing. It's what happens when the port is too small to handle the excursion of the driver, so the thing just dumps air so quickly through the port - instead of resonating the air to boost the low frequencies of the driver - that you can actually hear it. The remedy itself is simple, you make a port with a larger area. I'm kind of assuming that, since I've seen it a lot on smaller cheaper combos like this, that the ports are basically just a hole or two drilled into the baffle (the board that holds the speaker). Either make more of those holes, or make the one bigger, and problem solved.

The hard part is figuring out how to make the larger port longer, to compensate for making it bigger. The thing with those ports is that they use the air movement from the back side of the speaker cone (inside the box) to oscillate through a tuned port to reinforce the low-end coming off the front of the speaker - pretty similar in principle to blowing over the mouth of a half-full bottle. if you make the port(s) have a larger area, you start to mess with the tuning, and you'll need to make it longer in order to have the same tuning somehow. Of course, given that this is a 25 watt amp I don't think it'll be the end of the world (assuming the ports are just holes in the baffle and don't have tubes) if you just drilled another identically-sized hole or two, or just made the one hole bigger, BUT I've been wrong before.

 

[basscooker]

MCM 55-2960
20 bucks
8"
92 dB (meh)
80 watt (160 peak)
Fs 68; frq resp 48-6k (+/- ?dB)
Ive used these, pretty dang thumpy and full range.

Sound great in about 0.7 cuft, tuned to 48-50. No tolerance published regarding the frequency response, but I would say IME with them, that is probably +/- 6dB. Cool if you need a woofer on the cheap. I made a 4x8 with them (and 2- 1x8) they sound far and above better than their price would indicate.