TB vs. fostex suggestions

[Jeb-D.]

Help another newbee looking to build a first, single driver enclosure. It's going to be a bass reflex. The amp pushing them will be a 10W SET amp. Here are the 3 drivers I have narrowed it down to, please help me choose.

1320SB
1052SA
FE127E

Also, If I were to run multiple in parallel, is it true that efficency increases 3dB for each time you double the number of drivers?

Thanks!

[Paul Ebert]

Originally posted by Jeb-D.
Also, If I were to run multiple in parallel, is it true that efficency increases 3dB for each time you double the number of drivers?

Yes, but the impedance is reduced as well. Assuming each driver is the same, the resultant impedance is the impedance of one driver divided by the number of drivers in parallel (at least, I think that's right). So, 8 ohm drivers go to 4 ohms when there are 2 in parallel, 2.6 ohms for three and 2 ohms for 4. Your SET amp will probably not drive more than 2 paralleled drivers very well.

Also, when you have multiple full range drivers you can experience significant lobing issues unless the drivers are small and placed in close proximity.

I'd be happy to explain this in greater detail, if you'd like.

You might want to consider a bipolar design. Check out http://www.planet10-hifi.com/boxes.html for some bipolar designs using the FR125S. There's been some discussion about adapting these to the 1230. I'm strongly considering building a ML TQWT bipole using the 1230 or FR125S.

Good luck.

Paul Ebert

[Jeb-D.]

Here is the links to the specs.

http://www.partsexpress.com/pdf/264-846.pdf
http://www.partsexpress.com/pdf/264-828.pdf
http://www.madisound.com/pdf/fostexd.../fe127erev.pdf

[edjosh23]

Check out Omega Speakers
Omega

and here is a little design I'm going to build soon
hopefully when I get some money

The fe127 is a great choice, and from what I've heard and seen the other drivers are too.

Do you have a subwoofer in your room?
Are you okay with having 4 ohms speakers?
what is your budget?
Are there size restrictions?
Have you thought about larger drivers like the fe167?
How efficient do you want the speakers to be?

Josh

[Josephjcole]

I guess if your limited to 10watts than effeciency becomes a real issue. Which leads to the question of how big is your listening space, and how loud you want to listen. I've heard both the fostex 127, and the tang-band 1320SB. I'm sure you'ld be happy with either, the fostex is a bit more effecient though.
Joe

[Jeb-D.]

The listening room is very small, don't know the dimensions but it's my home office. And I was hoping for something that can do decent without a sub with music that dosen't have alot of bass. The Omega speakers are what got me interested in those drivers. FR125's have a nice curve but arn't very effecient. That 1052sa project looks interesting. Thanks for the input guys.

[edjosh23]

The Fe127s I built in GMs TL need a subwoofer. The Tang Bands will definately deliver some better bass than the fostex. In your situation I would forget about the fr125s. I'm guessing your associates might not like you turning up the volume too loud so they don't need to be super effecient.

I think that the TB W4-1052sa will give you the best bass. It not only has a lower fs, but a larger xmax as well. Personally I might try two of these in a bipole design. They will need some help up top, but I think they will sound great. You could also consider the modification .

Good luck,

Josh

[Josephjcole]

I second Josh's advice. A bipole TB W4-1052sa sounds pretty good for you.
Joe

[Dumbass]

Originally posted by edjosh23
I think that the TB W4-1052sa will give you the best bass. It not only has a lower fs, but a larger xmax as well. Personally I might try two of these in a bipole design. They will need some help up top, but I think they will sound great.

Based on the freq plots on McKenzie's page, no tweeter necessary IMO. Worth emphasizing that the McKenzie mod is both the glue ring and the EQ circuit. (Mods prolly not necessary for the rear-firing drivers?)

Looks like a fun driver to play with, especially if McKenzie's comments hold true.

[edjosh23]

I'm guessing without the modification or a tweeter they sound good if Omega sells them for $700 per pair.
Omega also says they need "as little as 10 watts" so I'm guessing your 10 watts should be sufficient.

Good luck and keep us updated,

Josh