Bass guitar amp/speakers

[Jorge]

Hello,

My younger son plays bass guitar semi professionally (he's a music student at the university).

I'm considering to buid for him a new amp/boxes combo, and would like a bit of your collective wisdom...

- Why are 4 x 10" speakers used for the high bass/lo mids box (and not just one)?
- Are class D amp (quite possibly Tripath based) reliable enough for this usage?

What I have in mind is a bi-ampli system, electronic Xo, 15" bass box (from 40Hz), something for high bass/lo mids, and a horn tweeter.

Power would be 300W/channel, class D, clasic power supply (not SMPS).

Thanks for your help,

[Tim__x]

4x10"s are used for the slight boost in efficiency.

A well made class D amp is more than reliable enough.

Euphonic Audio and Acoustic Image make class D bass amps. A large number of other companies make class D PA amps.

Bass cabinets really only need an f3 of 40-60hz, I would look in to PA drivers.

This section of the forum is pretty dead, you may want to ask in the loudspeaker and class D sections.

[Jorge]

Thanks, Tim

I've posted it here because I'm looking for user's opinion, and I felt the other forum posters may not be familiar with the pro/semi pro music environment (I for one!)...

The speakers I'm considering are PA ones, and the 15" in a ported box will go from 40Hz and produce 120dB @1m @300W.

Re the 4 x 10", if it's efficiency, one 10" (of the same make) is slightly more efficient - 120dB @1m @180W.
And with a 4th order L-R Xo at about 200~250Hz power handling (excursion) will be OK for a flat power response.

So, I feel I can do it with only a 15 and a 10 (plus horn). Reason is that he have to carry his gear around, so the smaller/lighter the better!
Same for the class D amp (but at least the first version will not have a SMPS).

[Brion55]

Had you thought of putting the 10" in a short, front loaded horn enclosure to increase efficiency? I've seen this done with good success.

[Jorge]

Thanks, Brion55

No, I didn't, due to size/weight constraints.

But why more efficiency if the 10" is already more efficient than the 15" one? Wouldn't the setup sound 'thinner' ?

[Brett]

Originally posted by Jorge
I'm considering to buid for him a new amp/boxes combo, and would like a bit of your collective wisdom...

- Why are 4 x 10" speakers used for the high bass/lo mids box (and not just one)?

As Tim said, for the sfficiency. However 4x10 cabs have some weird phasing issues depending on where you stand in front of them. Never heard a 4x10 I liked. They're also a weird shape that's hard to load into a car or move or carry

- Are class D amp (quite possibly Tripath based) reliable enough for this usage?

Power would be 300W/channel, class D, clasic power supply (not SMPS).

This si what I'm using for my rig at the moment. No reliability issues so far and a heck of a lot less weight. I have fans on the amp modules, blowing both across the heatsing and the PCB's. Not neccessary, but I like electronics cool, I had them anyway and I run the fans slow.

What I have in mind is a bi-ampli system, electronic Xo, 15" bass box (from 40Hz), something for high bass/lo mids, and a horn tweeter.

This is basically what my big rig will use, except I have a PAudio SN12C coax 12" (neo) because I got it for peanuts. I'm going to replace the HF driver with a BMS4552ND. When I get the BMS, I'll triamp, simply because I have a small T amp to drive it.

As you're in Brazil, are Selenium drivers cheap there? A rig consisting of
- WPU1505, ported. I haven't run the numbers but should be good.
- 10PW3 may be enough (Xmax is a bit low for my tates) in a sealed box. 300Hz xover.
- D205 on a flare that matches the dispersion of the MF driver at the xover freq, maybe the 5625?
It's a little bit of overkill, but I like my rig to be clean and loud, then use the pre and effects to shape the tone, so I have max flexibility. This is basically how my big rig was built before I got the PAudio neo coax. The 12" Selenium coax would be good too if it fits within budget.
Not sure what else is available to you locally.

Some suggestions:
- build the 15" into a box of it's own, and the 10 + horn into another. Reason is that depending upon how you shape the LF enclosure, you may be able to fit it into rear seats or boots (trunks) of cars more easily. The smaller bulk and mass are easier to shift and are better for the back to lift up and down. If your son also has to move his rig into backstage areas with poor or narrow access, this will be a lot easier.
- place the handles (and use steel ones) once the box is built so you can find the balance points of the box and the best position to lift it easily. After a long gig, your son will thank you for this.
- don't carpet the box(es) because it picks up smells like stale cigarettes and beer. Vinyl, epoxy or Rodkhard paint are better.
- buy a cheap furniture removalist's dolly to move the gear from the vehicle to the stage.

[Jorge]

Thanks, Brett

Speakers - unbelievable, but you can purchase Selenium in the US cheaper than we pay over here!

I intend to use Snake ESX155 and ESX310

http://www.snakepro.com/english/products.htm

It seems a decent brand, better prices than Selenium. My simulations shows Xo at 200~250Hz.

Your suggestions are quite in line with my thoughs - a ported cube for the 15", a closed box for the 10", horn and power amp.
Preamp, at least in the first version will be his foot pedals!

And very nice handling suggestions!

Take care,

[Brion55]

When you finish your project, post a photo so we can see it!

[penguinbass1]

How much are the snake pro's and where can you buy them also would their speakers and their tweeter be good for bass cabs Also how good are the selenium's

[Jorge]

Snake: I don't know how much they would cost or where they are sold out of Brazil, but here's the US contact:

Doug Holmquist
8074 Esterbrook Drive
Nashville TN USA
37221
Phone / Fax: (615) 516-0878

Selenium is a long standing brand, highly regarded for PA and musical instruments.
Parts Express for one sells it.