15" replacement speakers for Acoustic 106 cab

[4001]

Hey everyone,
I may need to re-load my Acoustic 106 (2X15) cabs with speakers that can handle the power that a GK 700RB II head will deliver.
Now, I know that there is a science to choosing the right replacement speaker so, if anyone that is good with speaker cabinet design and choosing the right speakers for cabinets could chime in with their .02, that would be great.
These cabs are 36" high, 28" wide and 15" deep. They are ported. If any of that that matters.

I'm not sure whether the speakers in the Acoustic 106 can handle the GK 700RB II head but I'm thinking because the cab was originaly paired with a (I think) 200 watt head, they would probably die when I played a few notes through it pretty quick.

Any ideas on good 15" speakers welcome.

[DukeLeJeune]

Too make an accurate assessment, I'd want to have the port dimensions as well so that I could estimate the tuning frequency. But off the top of my head, I'll speculate that the Eminence Kappalite 3015 (non-LF) is llikely to be a good candidate.

[Exploiter8]

"Eminence Kappalite 3015 (non-LF)"

I put a pair in my 30+ year old Peavey 215 (shallow) cab. I lined the cab with self adhesive foam from Parts Express and ran each speaker to it's own jack. Much lighter than the Madison Knight's (which were garbage) they replaced. I couldn't be happier with the end result!

X8

[4001]

I ran into a bunch of comments saying that the Kappalites had no real eye opening sonic qualitites. Most were just happy that the weight of the cab was reduced.
I'm not too concerned about the weight, (although I am not getting any younger) I just want great sounding speakers that can handle that GK 700RB II. It's no 1001RB and I'm not planning on trying to crack plaster or my neighbors, I just want my Acoustic 215's to sound great.

So, that's two votes for the Kappalite 3015's.

I had also read a TON of great stuff about these speakers right on this board.

[4001]

Originally Posted by DukeLeJeune

Too make an accurate assessment, I'd want to have the port dimensions as well so that I could estimate the tuning frequency. But off the top of my head, I'll speculate that the Eminence Kappalite 3015 (non-LF) is llikely to be a good candidate.

Here's a pic of the cab. (not mine, but mine looks the same)



I don't have the demensions as the cabs aren't at my house right now and I have no way of measuring the circles.

[Gizmot]

You can't go wrong with Electro-Voice 15s. They have old-style magnets, so they're not lightweight, but they're built solid and sound very balanced.

[4001]

Originally Posted by Exploiter8

"Eminence Kappalite 3015 (non-LF)"

I put a pair in my 30+ year old Peavey 215 (shallow) cab. I lined the cab with self adhesive foam from Parts Express and ran each speaker to it's own jack. Much lighter than the Madison Knight's (which were garbage) they replaced. I couldn't be happier with the end result!

X8

Hmmm....self-adhesive foam..
Does that help with the sound??
I'm used to people lining the cabs with fiberglass insulation. I'd rather use something like foam.

How did you do that? How do you reach up, around and into the cabs when you only have those small openings and you have to bend your arm up inside of it to stick it in there??
I'm confused.

Either way, it looks like you 'updated' that Peavey 215 nicely.

[Exploiter8]

With the speakers removed I had plenty of room for a tape measure and applying the panels after I cut to size. I've got a few combo amps that I've lined with the same foam. I've never had negative results by doing it. I didn't try the Kappalites without the foam, so I can't comment on before and after. I just figured if I was going to put such a high end speaker in I may as well go all the way and add the foam, redo the wiring, and run each to it's own jack. It sounds cleaner than the Black Widows it had originally, but according to Peavey, the cab was only rated at 200 watts, so I needed to upgrade.

X8

[4001]

Originally Posted by Exploiter8

With the speakers removed I had plenty of room for a tape measure and applying the panels after I cut to size. I've got a few combo amps that I've lined with the same foam. I've never had negative results by doing it. I didn't try the Kappalites without the foam, so I can't comment on before and after. I just figured if I was going to put such a high end speaker in I may as well go all the way and add the foam, redo the wiring, and run each to it's own jack. It sounds cleaner than the Black Widows it had originally, but according to Peavey, the cab was only rated at 200 watts, so I needed to upgrade.

X8

Wait.
Are you saying that you have each speaker to a seperate jack? Do you then use two speaker outs on the amp?
As if it is running two seperate 115's but in a 215?
Does this make the cab just loud as F--K?

Am I understanding this right?

Should I do this with my Acoustic 215? Two speakers, two seperate jacks?

[4001]

BTW, I'm really lacking in the electronics/ wiring dept when it comes to amps/speakers.

[billfitzmaurice]

Originally Posted by 4001

Here's a pic of the cab. (not mine, but mine looks the same)


.

You'll need to do some serious work to get that cab to work with modern drivers. With the excursion they're capable of the ports will make all sorts of noise, as they're at best 1/4 the area required for the volume of air passing through them. After making them large enough they'll have to be lengthened with ducts of the correct length to tune the cab to the drivers. The alternative is to use keep the power down to the 100 watts or less that won't cause port chuffing, but that pretty much makes getting new drivers a waste of coin.

[Exploiter8]

I'm not familiar with the Acoustic 215. I have two amp heads; a NeoPak 3.5 and an old ML 200, both GenzBenz. I have options when running the heads. The ML 200 is a bridged/mono type amp. It has a single 8 ohm minimum output at 200 watts or two 4 ohm minimum outputs at 100 watts each. My cab was originally 4 ohms, but that meant I could only push 100 watts using the 4 ohm minimum. I can now run each speaker with the 4 ohm minimum which is roughly 80 watts through each 8 ohm speaker for a total approximately 160 watts. The NeoPak 3.5 is 350 watts at 4 ohms if I just use that head. If I use BOTH heads then the ML 200 pushes one speaker at 200 watts while the NeoPak 3.5 pushes the other speaker at 225 watts for a 425 watt total system. I use a Morley A/B/Y to connect to my bass. Considering it never hurts to have a backup amp available, I figured I might as well run them both!

Two 8 ohm speakers (Parallel wiring) will combine for 4 ohms, whether they're wired together in the cab as a single out or combined at the amp as two separate cabs. Check your amp or owner's manual to see what omhage you can safely go down to when driving a speaker load.

Bill Fitzmaurice Is THE MAN with regards to this subject. I'm more of a shade-tree mechanic that reads threads and tries to put that knowledge to good use!

X8

[4001]

Originally Posted by billfitzmaurice

You'll need to do some serious work to get that cab to work with modern drivers.

Well, certainly there are some decent replacement 15's available if I needed to put some in that could handle the GK 700RB II head. No?
I was thinking about JBL E-140's.
Would those be considered 'modern'?

I don't know squat about customizing amp cabinets, tubes, glue, clamps etc.

I just want to have a good plan if/when the speakers fry.
I'm $300.00 away from getting those GK heads.

[billfitzmaurice]

Originally Posted by 4001

Well, certainly there are some decent replacement 15's available if I needed to put some in that could handle the GK 700RB II head. No?
I was thinking about JBL E-140's.
Would those be considered 'modern'?

I don't know squat about customizing amp cabinets, tubes, glue, clamps etc.

I just want to have a good plan if/when the speakers fry.
I'm $300.00 away from getting those GK heads.

Read my post again. To get a useful result with drivers capable of handling more than about 100 watts total without reaching their excursion limits the cab basically needs to be redesigned and rebuilt. Just dropping in new drivers is like taking the stock engine out of a '65 VW Beetle and replacing it with a Porsche Boxster engine. Unless you change the suspension, wheels, brakes, tires and everything else it will still be a '65 Beetle, but now one you're likely to wrap around a telephone pole.

[Oren Hudson]

4001 Maybe you should wait until you have actually tried your GK 700RB II with the Acoustic cab? You may be surprised and pleased with the results. I have an Acoustic 106 cab with the original speakers in it. It can handle a good bit more than you might think. As you stated, you're not wanting to knock the plaster off of your neighbors wall. I believe that Bill F's point would direct you towards not replacing with newer speakers and I agree. If your 106 has original speakers and they need help, I'd have them rebuilt and go with them. After all, Acoustic made some great gear and designed, like many quality companies, the cab and speakers to go together. Just because you have more power than your cab is rated for does not mean that you're going to fry them right off the bat.

[4001]

Originally Posted by billfitzmaurice

Read my post again. To get a useful result with drivers capable of handling more than about 100 watts total without reaching their excursion limits the cab basically needs to be redesigned and rebuilt. Just dropping in new drivers is like taking the stock engine out of a '65 VW Beetle and replacing it with a Porsche Boxster engine. Unless you change the suspension, wheels, brakes, tires and everything else it will still be a '65 Beetle, but now one you're likely to wrap around a telephone pole.

Sorry Bill, I wasn't trying to insult your intelligence.
I had read that others have had some sucess with replacing the speakers with others and the JBL's were mentioned as being excellent.
So, being one that never replaced speakers in a cab I didn't know that the sound and performance would be so affected.

[4001]

Originally Posted by Oren Hudson

4001 Maybe you should wait until you have actually tried your GK 700RB II with the Acoustic cab? You may be surprised and pleased with the results. I have an Acoustic 106 cab with the original speakers in it. It can handle a good bit more than you might think. As you stated, you're not wanting to knock the plaster off of your neighbors wall. I believe that Bill F's point would direct you towards not replacing with newer speakers and I agree. If your 106 has original speakers and they need help, I'd have them rebuilt and go with them. After all, Acoustic made some great gear and designed, like many quality companies, the cab and speakers to go together. Just because you have more power than your cab is rated for does not mean that you're going to fry them right off the bat.

You're right Oren. And you aren't the first one to say that this cab can do the job, and also about getting them rebuilt to specs. I guess I'm worrying about it too much.

$250.00 from getting the amps.
Not long now.

[Bill Whitehurst]

My first thought was the same as Duke's.
I think Bill pretty much nailed the limitations.
With a well thought out rebuild, I think there is hope.
On the other hand, maybe someone would give you enough
for a vintage Acoustic cab to let you buy somehing more
suited to your needs.
Ask this same question on teh Unofficial Acoustic forum.

[4001]

Originally Posted by Bill Whitehurst

My first thought was the same as Duke's.
I think Bill pretty much nailed the limitations.
With a well thought out rebuild, I think there is hope.
On the other hand, maybe someone would give you enough
for a vintage Acoustic cab to let you buy somehing more
suited to your needs.
Ask this same question on teh Unofficial Acoustic forum.

I was referring to the speakers being 'rebuilt' as in re-coned to specs.
I'm running a stereo rig so I'll have two GK 700RB II heads and two of the Acoustic 215 cabs , so I'll see how all four speakers with the two heads sounds.
It might just be awesome.
I'm not playing Madison Sqaure Garden anyways.

[Chuck King]

There was a thread recently on the unofficial Acoustic Control Corp. forum suggesting a specific model of new Fane speakerss as having a very similar character to the original Acoustic speakers, but they can handle a lot more power. Unfortunately for reasons I don't quite understand that site is blocked from my office computer, but if you dig around in the Acoustic Club thread you should be able to find a link to the forum, and a search for "Fane" should bring up the thread.

However, I did some poking around and it looks like Fanes are tough to find on this side of the Atlantic.