8" wide MCM TruckTuba
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8" wide MCM TruckTuba
Purpose: I decided to make a horn subwoofer for my college dorm room. The room is about 15'x15'. I wanted a small form factor that would fit right next to my desk, good output and acceptable extension, and low cost. The TrT fit the bill perfectly.
Build: This is the easiest build I've done yet. It helps that the 8" wide cab does not require internal bracing other than at the driver baffle. I only used a jigsaw, circular saw, and basic measuring tools to build this cab. I also used 1 tube of PL, a pint of Duratex, a pint of red paint for the mouth, 8 steel corner protectors, 2 small rigid casters, and one 4x8 sheet of 1/2" MDF. Yes, I used MDF and it turned out great. I used MDF for a few reasons. 1) It's inexpensive, 2) it doesn't warp, 3) it doesn't split when cutting with the saw, 4) it was easiest to acquire, and 5) I didn't require the durability of Baltic Birch since the sub is staying in either my dorm room or car.
Performance: It's about the equivalent of the Autotuba's performance. I didn't build it as big as possible, nor as small as possible. It sounds good in the dorm room and is located about 3' away from the listening position. I was surprised at the low extension of the TrT, but it's obvious that this design greatly benefits from the cabin gain of a vehicle, which is its intended environment anyway. It rapidly runs out of steam outdoors or in an open garage. I will say I am quite disappointed in the MCM 8" driver, which rapidly hits its excursion limits in the low frequencies, and I will eventually upgrade to a GTO804 or Infinity 860W. I'm overpowering it with a SD300 300w plate amp right now in anticipation of this eventual upgrade.
Overall I'm very happy with it, and it's perfect for my dorm room, if a bit overkill. Anything over 3v draws negative attention from neighbors.
Pics:
Before attaching the final side (yes, that is a CNC router in the background. College is awesome )
Finished:
Build: This is the easiest build I've done yet. It helps that the 8" wide cab does not require internal bracing other than at the driver baffle. I only used a jigsaw, circular saw, and basic measuring tools to build this cab. I also used 1 tube of PL, a pint of Duratex, a pint of red paint for the mouth, 8 steel corner protectors, 2 small rigid casters, and one 4x8 sheet of 1/2" MDF. Yes, I used MDF and it turned out great. I used MDF for a few reasons. 1) It's inexpensive, 2) it doesn't warp, 3) it doesn't split when cutting with the saw, 4) it was easiest to acquire, and 5) I didn't require the durability of Baltic Birch since the sub is staying in either my dorm room or car.
Performance: It's about the equivalent of the Autotuba's performance. I didn't build it as big as possible, nor as small as possible. It sounds good in the dorm room and is located about 3' away from the listening position. I was surprised at the low extension of the TrT, but it's obvious that this design greatly benefits from the cabin gain of a vehicle, which is its intended environment anyway. It rapidly runs out of steam outdoors or in an open garage. I will say I am quite disappointed in the MCM 8" driver, which rapidly hits its excursion limits in the low frequencies, and I will eventually upgrade to a GTO804 or Infinity 860W. I'm overpowering it with a SD300 300w plate amp right now in anticipation of this eventual upgrade.
Overall I'm very happy with it, and it's perfect for my dorm room, if a bit overkill. Anything over 3v draws negative attention from neighbors.
Pics:
Before attaching the final side (yes, that is a CNC router in the background. College is awesome )
Finished:
Re: 8" wide MCM TruckTuba
Thanks for the review of the Trt. I am considering building one of them for a work truck, just cuz. I am also not a big fan of the MCM driver:
That's what happened when I was abusing it. They are cheap and I have a couple extras laying around, so it wasn't a big deal to me when it happened, but it did catch on fire which is a little concerning. Luckily it didn't continue to burn.
That's what happened when I was abusing it. They are cheap and I have a couple extras laying around, so it wasn't a big deal to me when it happened, but it did catch on fire which is a little concerning. Luckily it didn't continue to burn.
2 THTs, 2 TLAH, SLA curved, 1 8-AT, 1 AT JBL 1002D, 4 Otop12s, Jack 12, TT with Eminence 10", 2 SLAs, 1 T30 slim, 2 T30s (2-10" each), SLA Pros, TrT.
Re: 8" wide MCM TruckTuba
I don't get all this hate over the MCM driver(s). Yes, it's cheap, yes, it's not as good as the Dayton, JBL, Eminence, ect. You get what you pay for. The plans specifically state that it's the least expensive recommended driver. With that being said, I have 2 AT's with the MCM 55-2421 and they're nothing to rave about, but they get the job done. And I don't abuse them!
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102
- Bill Fitzmaurice
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Re: 8" wide MCM TruckTuba
The cab would probably be in rough shape too, if you tossed a grenade or two inside.67baja wrote:Thanks for the review of the Trt. I am considering building one of them for a work truck, just cuz. I am also not a big fan of the MCM driver:
That's what happened when I was abusing it. They are cheap and I have a couple extras laying around, so it wasn't a big deal to me when it happened, but it did catch on fire which is a little concerning. Luckily it didn't continue to burn.
It's a 150w driver!
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Re: 8" wide MCM TruckTuba
This thread leads perfectly to something I was thinking about the other day...
The Tang Band 8" costs almost 2x what the MCM does. What does that 2x expense get you in sound quality/output?
The Tang Band 8" costs almost 2x what the MCM does. What does that 2x expense get you in sound quality/output?
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Re: 8" wide MCM TruckTuba
SQ is mostly a function of the cabinet, not the driver. It does get you a little more volume. Next time I'll go straight for the GTO804, which has 3mm more xmax. If you're going to take the time to build this cabinet, why not spend $30 or so more for a better driver?
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Re: 8" wide MCM TruckTuba
Because not everyone's goal is to listen at levels that damage their hearing. If you can't enjoy music without injuring yourself, maybe you are missing something. Once that damage is done, you might ask, " what was I thinking?, what have I done?" You don't get it back, no matter how cool you are.bassmonster wrote:SQ is mostly a function of the cabinet, not the driver. It does get you a little more volume. Next time I'll go straight for the GTO804, which has 3mm more xmax. If you're going to take the time to build this cabinet, why not spend $30 or so more for a better driver?
Re: 8" wide MCM TruckTuba
In some cases, it's what is affordable, .....and at the same time give great rewards! A few years ago, after many years of being in want of a sub, I got to build a sub (AT) because of the low cost. All my dollars, at the time, had to be accounted for, and the AT was/is a super addition to the factory radio. Aaaand, my AT can easily outrun the factory radios that I have had so far.bassmonster wrote:SQ is mostly a function of the cabinet, not the driver. It does get you a little more volume. Next time I'll go straight for the GTO804, which has 3mm more xmax. If you're going to take the time to build this cabinet, why not spend $30 or so more for a better driver?
TomS
- Bill Fitzmaurice
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Re: 8" wide MCM TruckTuba
FWIW my TT and David are both loaded with the MCM, they're both going on ten years of use, and both go as loud as I have use for.bassmonster wrote:If you're going to take the time to build this cabinet, why not spend $30 or so more for a better driver?
+1. While you're checking out the prices on drivers also check out the prices on hearing aids.Because not everyone's goal is to listen at levels that damage their hearing.
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Re: 8" wide MCM TruckTuba
Followup question, Bill: if you could design, from the ground up, the "perfect" subwoofer driver for your cabs, what would the TS parameters be?Bill Fitzmaurice wrote:FWIW my TT and David are both loaded with the MCM, they're both going on ten years of use, and both go as loud as I have use for.
- Bill Fitzmaurice
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Re: 8" wide MCM TruckTuba
There is no 'perfect'. For instance, the LAB 12/15 are very nearly ideal in the T60, but that's because I designed the T60 around the LAB 12/15, not the other way around. By the same token I designed the Truck Tuba around the MCM specs, not because it has specs that are perfect for the design, but to make the design perfect for the driver specs. You must use what's available.Ryan Sober wrote: if you could design, from the ground up, the "perfect" subwoofer driver for your cabs, what would the TS parameters be?
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Re: 8" wide MCM TruckTuba
I will say that a TrT loaded with the MCM is one of, if not the best, values for performance and sound quality. I built this for under $100, finished, and it only took me about 8 hours (cumulative) to build. You don't even need an amp that can put out all 130w if you don't plan on blasting it.
As for the volume, maybe I'm just spoiled by the dual TT (which is about 3 times as large as this thing!), but again, it's plenty for regular listening. It's like a fast car. You really only need enough horsepower so the car can get out of its own way and drive reliably at highway speeds, but where's the fun in that?
Next up, I'm building my sister a Truck Tuba as a Christmas/birthday present. This one will use the old 8" ported sub amp and driver, so it'll be limited to about 40w and the amount of excursion that the old driver has.
As for the volume, maybe I'm just spoiled by the dual TT (which is about 3 times as large as this thing!), but again, it's plenty for regular listening. It's like a fast car. You really only need enough horsepower so the car can get out of its own way and drive reliably at highway speeds, but where's the fun in that?
Next up, I'm building my sister a Truck Tuba as a Christmas/birthday present. This one will use the old 8" ported sub amp and driver, so it'll be limited to about 40w and the amount of excursion that the old driver has.
Re: 8" wide MCM TruckTuba
1. The "regular" AT has a sealed rear chamber. This one appears open. Is the "cabin" of the truck the "sealed rear chamber"?
2. Would it matter if the driver were positioned 180 degrees so the front of the cone was loaded instead of the rear?
2. Would it matter if the driver were positioned 180 degrees so the front of the cone was loaded instead of the rear?
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Re: 8" wide MCM TruckTuba
Good questions. I think (Bill will have to confirm) that the driver is close enough to the mouth that it behaves like a tapped horn, as does the Table Tuba. A boundary (like a wall) provides acoustic load, at least for the Table Tuba.
When switching phase from 0 to 180, the sound changes.
When switching phase from 0 to 180, the sound changes.
Re: 8" wide MCM TruckTuba
I meant actually unbolting the driver, flipping it over, and bolting it back in with the magnet sticking out, not in. Would that make a difference?