DETUNED CABINETS ANYONE?

[Paul86]

I don't know if this has been posted before.
Has anyone here ever tried detuned cabinets with their Wrecks?
If you have, could please report? Pix would also help.
I'm torn right now. I was going to build me a 2X12, now I have to have a 4X12. Maybe a 2X12 detuned would be the best of both worlds?
Anyway, any info appreciated.

[dartanion]

I had a cab that I used in detuned form, but I offered it up as part of the Mark Durham Memorial Prizes. I can't say enough good things about a detuned cab. I truly miss mine and will be building another one soon.

Mine was a 212 cab that I pulled one of the speakers out of for detuned mode. Of course your cab needs to be closed back for this to work, but that's somewhat obvious. You still get a directional projection of sound, but you lose the over accentuated bass that some closed back cabs have, which is good in my mind. It also opens up the tone with much more present upper mids and highs, yet they stay very crisp and sparkly.

I have used mine with my 18watt variants for gigging and with a few other heads that I have. It even sounded really good with my JCM800. Mine was loaded with a very well used and old AlNiCo Blue Dog.

Here's a photo of my main gig rig before I yanked on of the speakers and before I gave away the cab.

[Mark]

Dear Paul86

Good call, this is something that I have suggested to the group a long time ago. The Express can be built on par with an amp KF himself would have built. The speakers and box are another matter, I think someone mentioned Ken like the Ampeg 4 X 12" yet we don't build that when building these amps.

Dartanion, great build!

[908ssp]

I have had two. I decided I like four Greenbacks better then 2 but for my SLOClone two EVM12Ls work great.

[IMG:768:1024]http://i146.photobucket.com/albums/r245 ... lth800.jpg[/img]

[Paul86]

Alex,
Your rig looks awesome!
Funny enough, I was thinking exactly along the same lines - two EV's in a detuned cab!
Can you tell me a bit more about what to expect from such a design?
And Dartanion - beautiful rig!

[dartanion]

Hey Guys,

Thanks for the kind comments.

[jelle]

Mark Knopfler and Eric Clapton supposedly used a 4x12 with only two EVM 12L's in it in the 80's. The other two holes were left open. This is detuned as far as I know...

Jelle

[908ssp]

Alex,
Your rig looks awesome!
Funny enough, I was thinking exactly along the same lines - two EV's in a detuned cab!
Can you tell me a bit more about what to expect from such a design?
And Dartanion - beautiful rig!

It has smooth warm tone. I think the very slight natural delay works especially well with the EVs. Where other speakers soften the attack and the articulation of the note by distorting the EVs don't do that and they can be a bit hard and unforgiving. But the detuned effect smooths that out. I honestly haven't tried the EV cab with anything other then the SLO.

[captain_rusty]

So would an alternative be to cut ports in the speaker baffle, or wouldn't they be large enough? A 12" diameter hole seems quite big

[deiseldave]

I have (1) Celestion Blue in an Avatar 2X12 cab, and left the second speaker out (Detuned), and to my ears, it boosts the low mids a bit too much. It does have good bottom, but it sounds like it's such a wide boost, that it also increases the boxiness frequencies.
I don't really care for it, but a guitar player buddy of mine likes it a lot (but he also likes fiberglass underwear ).
I do have an EV-12L, and will give it a try in there. Maybe I'll like it better.
A while back I did some emulations of the detuned cab in Eminence Designer, using different speakers (EV-12L, Celestion Blue, Eminence GB-12, Celestion V-30).
I will model them again to make sure, but my memory is that the Blue's graph showed a larger boost in the low mids than the rest, which is why I tried it in the cab first (thinking I would like it... but I didn't). The GB-12 had the second largest hump, and I seem to remember the V-30, and EV-12 as being more flat in the low mids.
I'll run the models again, and if anyone is interested, maybe I'll post the freq response graphs.

[dartanion]

So would an alternative be to cut ports in the speaker baffle, or wouldn't they be large enough? A 12" diameter hole seems quite big

For it to be detuned, you would need a port that is equally as large as the speaker cutout or larger. Anything smaller, and you are tuning the cab with the port.

[captain_rusty]

So would an alternative be to cut ports in the speaker baffle, or wouldn't they be large enough? A 12" diameter hole seems quite big

For it to be detuned, you would need a port that is equally as large as the speaker cutout or larger. Anything smaller, and you are tuning the cab with the port.

So it's closed-backed, but open-fronted... intriguing

[deiseldave]

So would an alternative be to cut ports in the speaker baffle, or wouldn't they be large enough? A 12" diameter hole seems quite big

For it to be detuned, you would need a port that is equally as large as the speaker cutout or larger. Anything smaller, and you are tuning the cab with the port.

So it's closed-backed, but open-fronted... intriguing

I thought any hole in a sealed enclosure is a tuned port or vent.
"Tuned to what ?", would be the question.
My understanding is that the port can be back or front, and it doesn't make much difference phase wise. But that, you should try to set up ports for minimum direct leakage (so that the sound waves have to reflect a bit before escaping the cabinet).
I would think the minimising of direct leakage cuts down on phase cancellations. I haven't read that, but it makes common sense to me.
Nevertheless, I have read that minimising direct leakage is a good thing, and have noticed cabinet designs from top companies definately follow this practice.
However, for guitar, phase cancellation might be your friend, if you are using it to attenuate unwanted frequencies, and sculpt a particular sound. That would fall too far into the realm of "space-aged, high-tech voodoo" for me though.
Here's a plan for a nice ported EVM-12L cab that I absolutely love for guitar.
http://archives.telex.com/archives/EV/B ... 0Plans.pdf

[captain_rusty]

Of course, the point here is that it's not tuned, but "de-tuned"...