Ampeg V4B 2x15 Folded Horn Cabinet Speaker Conundrum

[someparts]

Hey all.....

Well, just picked up a 70s Ampeg V-4B 2x15 folded horn cabinet. You don't see them very often but there are a few guys on TB that have them...sort of like a bigger Acoustic 301 "W" cab but with two 15s in internal sealed boxes instead of the single 18. Certainly they aren't popular anymore due to the ultra-mega-massive size and antiquated design, but I've been trying different brands of 70s horn cabs in a vintage tonequest and since this matches my SVT flatback cabs I thought it might be a keeper. It's in pretty good shape but both of the original EV EVM 15Ls cones are shredded. I have a pair of Black Widows and a pair of Kappa Pro LFs on hand that have both higher power handling and excursion, but BFM noted somewhere that higher excursion might actually be worse for this style of cab? So recone the EVMs or swap?

[jhfishn]

I had a friend that had the V4B and an SVT Cab mixed with an SVT head back in the 70's and I'm almost positive his original speakers were Altecs.

It's been a long time so I could be wrong but I think that's what was in there in his.
I'd be more into seeing if I could find the Altec (only because that's what my friends had and I liked that sound very much) But ........... my 2 cents would be to recone the EV's

Nonetheless it was one powerful rig and what a nice full range sound he got.

I had 2 SVT cabs with the SVT head and moved over to the Acoustic 370/301 combination.

The thing I missed with the 2 SVT's was the bottom that the reflex cabs gave .... but then again I missed the punch of the 10's with the Acoustic ..... so .... you may have the best of both vintage worlds there if it matches with your SVT cabs once you get the speakers changed.

Now ............ the real question .......... how do you move it!

Best of luck with it ......... it certainly sounds like a very cool combination.

[someparts]

One vote for recone....thanks!

These cabs started with Altecs and then later went to the EVMs. I guess Geddy used them as part of his touring rig for a while. Same situation wanting to mix cabs, I've been playing a pair of 301s so the SVT cab with 10s sounds REALLY crisp in comparision.

[billfitzmaurice]

Originally Posted by someparts

So recone the EVMs or swap?

Recone. Folded horns of that sort have very poor midrange, because the cab design filters them out. You can compensate for that somewhat with a driver that has very high sensitivity in the mids, which the EVM does. The last thing you'd want to do is to put in an LF suffix driver, which has poor midrange sensitivity. BTW, the JBL PA horns that were the model for this and similar Acoustic horns were only intended to be run to 1kHz, a detail that the cloners overlooked.

[jackcheez]

How will you be running it ? What head... with other cabs... ?


The reason I ask is because an SVT head would blow the original speakers.

As far as how the other speakers would sound, try 'em and find out.

The Black Widows would weigh a ton tho.

[billfitzmaurice]

Originally Posted by jackcheez

How will you be running it ? What head... with other cabs... ?


The reason I ask is because an SVT head would blow the original speakers.

Why?

[someparts]

Thanks Bill. I figured the LFs would be nothing but boomy bottom. The Widows are from the 80s....an old design in their own right and seem to have some mids but I've never really looked at specs on them.

As far as power handling, the first version EVM 15s are supposedly rated 200w RMS each, so should be okay even as a stand-alone. I think the Altecs were somewhere in the 70-100w range. Power is either an SVT-VR or SVT-II non-pro and was thinking of running with an 810. Reconing is looking pretty good at this point.

Bill, there's tons of room behind the grille on this cab....if I wanted to run a couple stealth sealed back 8" mids what crossover point would you recommend?

[billfitzmaurice]

Originally Posted by someparts

Bill, there's tons of room behind the grille on this cab....if I wanted to run a couple stealth sealed back 8" mids what crossover point would you recommend?

1kHz. Run a pair of them vertical in the upper horn mouth. If you did that then the midrange response issue of the woofers is moot and you could use neos, say Deltalite II 2515s, and end up with less weight even after the addition of the mids. You'd also get a lot more low end outout, as like with almost all woofers the EVs aren't limited by power, but by excursion, and the 2515 has 25% more than the EV. You could even go 3015 or 3015LF, but the cost would be way up there.

[someparts]

Thanks Bill. Going to re-cone and see how it works with the 8x10 flatback as is. This full range idea is very interesting though. If I end up doing it will report back.

[Alex1984]

The V4B should sound great through an 810 flatback. Get the EVs reconed!