Dual Loaded Table Tuba by a Teenager

[Michael Ewald Hansen]

would it be the same if I were to wire two single loaded cabs parallel?

Yup, you get the same result by paralleling 2 cabs as paralleling 2 drivers in 1 cab



@Bassmonster - good to hear you are making progress! I use a wood filler puttybrand called "PolyFilla" - its perfect for cabs as its very easy to work with, dries very fast and 1 layer of duratex completely covers it up.. The specific version of Polyfilla i use is called "Træflex" don't know if something similar can be found in the US, but its cheap here and very nice..

http://www.traelasten.dk/ImageRoot/Imag ... 0_zoom.jpg

There is also a company called Henkel(loctite in the US - makes PL) which has a product called Plastic Padding (Chemical Wood) which is quite easy to work with and pretty much as strong as wood itself..

Can't wait to hear your reaction on using Duratex on your cab - it amazed me completely the first time i used it

[2Channon]

Thanks for the help. I spent all last night searching and reading but to no avail. I guess I didn't use the magic words
So that is 4 for the driver + 2 for a single loaded cab = 6. Divide by 2 when I wire 2 TTs together and I get a 3 Ohm load. Is it OK to be showing such a low Ohm load to the amp because you will be limiting the output, by measuring and limiting the volts out, so as not to over drive the drivers?
Is your Bash 300 staying pretty cool?
Thanks, I'm learning a lot.

[bassmonster]

Is it OK to be showing such a low Ohm load to the amp because you will be limiting the output, by measuring and limiting the volts out, so as not to over drive the drivers?

A lower-than-rated ohm load is dangerous for an amp. The Bash is rated for 4-8 ohms. I don't know the effect of driving it at 3 ohms. I don't even know how many ohms mine is at, about 3 IIRC. I'm bad with this sort of thing. It hasn't completely blown yet, so I must be OK.

Is your Bash 300 staying pretty cool?

It normally stays fairly cool. Earlier in this thread I made a custom box for it with a big fan in the back, mainly DIY overkill. I drove it pretty hard today about 1/3 volume with some Decibel by Original Sin, 36hz main bassline, without the fan on in my custom amp cabinet, and the amp cut out on me after about 10 minutes of high volume use with that song and other low low songs. To be fair it was being put under pretty harsh abuse. I might as well have been giving it a constant 36hz sine wave with Decibel, that song has brutally low bass all the way through. The tools in my garage by then about had it!

[bassmonster]

Well, I prepped and painted the horn mouth today. "Burnt Peanut Red" was the color, a dark red basically, maroon-ish. The flash in the pic makes it look a tad lighter than it really is.



The picture really doesn't do it any justice. In real life this thing looks wicked.

[maxmercy]

I remember my Table Tuba. Never had felt 30Hz with that kind of clean spl in my home prior to it. I remember re-listening to so many tracks/films after I built it...

Now you need 2+ THTs, to reach another 10+Hz lower...

JSS

[bassmonster]

I remember re-listening to so many tracks/films after I built it...

I have done just that, to find the bass guitar in songs much more full, and the drum kicks more "kicking" than the dull "thudding" of my old ported sub. Even the radio is much more exciting to listen to.

Now you need 2+ THTs, to reach another 10+Hz lower...

This will be the end of me. It's been in the back of my mind ever since I fired it up for the first time, but I won't be able to build a THT till I'm out of the house, it's just too big, I'd have to build it ultra slim, 12" loaded for the PAF (parent approval factor). By then this 24" TT would be pretty comparable to it in terms of extension anyway.

[Gregory East]

Most of the prep work for Duratex and paint will happen tomorrow after school. I have a super small gig with it Sunday w/ less than 50 people- I'm playing bass for our church band. Anyone ever used a TT as a bottom for a small bass rig? It works fine so far, at least in my room. Rattles the light fixture to death on low A.

Detuned 5 string?

My BAT does very well as a (relatively low volume) bass guitar / PA sub.

[bassmonster]

Detuned 5 string?

Low A for me anyway, cheapo Ibanez 4-string with active pickups.

[Drey Chennells]

I remember my Table Tuba. Never had felt 30Hz with that kind of clean spl in my home prior to it. I remember re-listening to so many tracks/films after I built it...

Now you need 2+ THTs, to reach another 10+Hz lower...

JSS

Right. A little shop story..Before shipping a quad of THT24/15 I faced the pairs towards eachother and ran 20hz at full throttle (outdoors). Of course I stood between them . I will not do that again. The fight/flight/nausea was intense and felt like

[bassmonster]

I stuck my head in the mouth of my TT when running at 5 volts, my vision blurred when the bass hit. I can't imagine what standing between 4 THTs would be like. A jackhammer right in the stomach. Sounds fun.

Also, quick question. My room has a terrible room mode. The bass is nonexistent in the center of the room where I usually am, but is immense in the corners. I have tried different placement options, and it hasn't helped. I know that two single loaded TTs would have been the best option, but this TT is going in the car in about a year anyway. I actually found that the placement specifically recommended against in The Plans works best. With the mouth of the horn facing out of the corner instead of facing into the corner. There's nothing I can do about it, right?

[maxmercy]

Every room is different, and with a single bass source, experimentation and compromise are par for the course. You will need some sort of EQ and measurement capability to make your system as flat or as boosted as you'd like.

JSS

[bassmonster]

Thank you for the pointers maxmercy. Unfortunately I don't have any EQ other than the primitive EQ on my old receiver, and I don't have any measuring equipment either. I guess I'll just place it where it sounds best without intruding too much into the main area of my 11x12 room.


On an update, I did some prep work last night. I put another coat of red inside the horn mouth and sanded the outside and put wood filler in the screw holes. I did some sanding early this morning, and it looks good. More work later today.

[subharmonic]

Put the horn where you want it to sound best. Then walk around the room and find the spot it sounds best. Put it in that spot or the next reasonable one.

[bassmonster]

Thank you for the advice. I will try that after it's all finished. Would it matter which way the horn mouth was pointed while it was in the center of the room? I wouldn't think so, as bass is omnidirectional...

[Gregory East]

Put the horn where you want it to sound best. Sit on top of it I keed I keed.

The placement rules get slackened off in small rooms. Afaik the only hard and fast one is, use what works at listening posistion.