Author Topic: Cabinets for biamping from an sf2  (Read 358 times)

hgregs

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Cabinets for biamping from an sf2
« on: March 21, 2011, 06:21:37 PM »
i'm about to get a new cabinet(s), and am wondering who makes a bass cabinet designed for biamping (lows vs highs)? i thought it would be fun to explore using the the separate outs from the sf2 in a chA:highpass, chB:lowpass type setting. but it seems all the cabinets i come across are fullrange. i know the fearful design uses an internal crossover. i'm looking for something that would take 2 separate amplified signals, or 2 separate cabs for the separate signals.

elwoodblue

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Cabinets for biamping from an sf2
« Reply #1 on: March 21, 2011, 10:13:44 PM »
Can't help you as choices go ...my cabs are homemade...but I can say from experience you are in for
  some fantastic and deep tones splitting the SF-2 into two cabs.
 ....with crossover on the F-1X ( I set mine around 140hz ) it adds an amazing amount of versatility.  
 
  Expect to experiment for a while once you get it set-up.  
  I'm still learning new ideal settings

skyboltone

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Cabinets for biamping from an sf2
« Reply #2 on: March 21, 2011, 10:27:59 PM »
There are a variety of issues here hgregs. First of all, the reason the crossovers are in the cabinet is to protect the high frequency speakers from low frequency energy. A horn type tweeter will die a quick death when subjected to high energy low frequency. The reason we crossover into the low frequency drivers is so we don't waste HF energy into a driver that cannot reproduce it, or reproduces it poorly.  
 
So, any full range box can have it's low frequency and high frequency drivers disconnected from the crossover and tapped out via 1/4 connectors on the back of the box. If the HF side has more than one driver you need to determine how the crossover works. If you are looking at a 410 cab with tweeter I see almost nothing to be gained by biamping. If you are going to run a pair of 15 on the low box and 2 or 4 10 in the high box, just use the biamp crossover to send everything below about 400 or 500 hz to the 15's and leave the 10's box alone letting it see 400 and up. If you are buying a box with one 15 and one tweeter, you are almost doomed to kill the tweeter because the internal crossover will have been designed to limit the energy going to the tweeter. You can try, but just remember to keep that channel REALLY low until you are balanced. Or, reverse engineer the crossover so you can keep it's power limiting intact and make connection to the tweeter through the high side of the crossover.
 
So, you must provide a way of isolating the Hf and Lf before it is amplified and then use separate amplifiers for each frequency set or one channel of a stereo amp for Hf and one for Lf.  
 
Let us know what equipment you are going to use and it can become clearer.  
 
Dan
 
Alembic makes a device called the F1-X that provides this for you. It also has a tube driven front end, tone control. and an effects loop for reverb or other line level effects. I was unaware that the SF-2 had a crossover too. But if so it would work.  
 
You need to study up and understand what I've just related to you before you start. It's not rocket science but it can be costly to get it wrong.

elwoodblue

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Cabinets for biamping from an sf2
« Reply #3 on: March 21, 2011, 10:57:18 PM »
Great detailed info Dan,
 The SF-2 doesn't have a crossover, that's in the F1-X.
 
Elwood

hgregs

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Cabinets for biamping from an sf2
« Reply #4 on: March 22, 2011, 06:34:37 AM »
i may be assuming too much, but i thought that if i used the high-pass filter on ch:a and the low-pass filter on ch:b and used the separate outs on the back to feed separate amps (or separate power amp channels), i would effectively have a biamped unit (working the same way a crossover would work).  
 
what i'm trying to do: just see what cabinet options there are besides the typical full-range cabinet. for my applications (mostly smaller clubs), a 4x10 works fine. we do a few outdoor gigs in the summer - which would need another cab.

skyboltone

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Cabinets for biamping from an sf2
« Reply #5 on: March 22, 2011, 11:15:22 AM »
I can't tell you. I'm not familiar with the SF-2 but as Elwood has already stated, he uses the F1-X crossover with the SF-2. I'd love to have one to play with, maybe next year. I personally prefer a 15 and 2-10 over a 4-10. You can experiment with the SF-2. It sounds feasible but I just can't tell you for sure. Good luck and keep us informed on yer progearsh.

elwoodblue

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Cabinets for biamping from an sf2
« Reply #6 on: March 22, 2011, 12:04:48 PM »
That sounds like it would work (if you are only using the filter signal and not the direct signal...which is part of the beauty of the SF-2 *), though I think you are losing flexibility by not using a separate crossover.  
   
  Doesn't the SF-2 create a resonant peak close to the cutoff frequency? With a separate crossover you could put that peak anywhere in the cabs spectrum.
  * And   even more importantly, the direct signal for each channel is then filtered through the crossover ...otherwise you will have a full range signal going to each cab.
 I have my SF-2 after the crossover (F1-X)
 
(I think I got that right, happy to be corrected if I mis-stated the SF-2 functionality )
 
I'm using a 15 cab on the bottom and a 12 for the top...no shortage of treble available with the 12...I don't understand the horn thing in bass cabs ;)

edwin

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Cabinets for biamping from an sf2
« Reply #7 on: March 24, 2011, 12:18:36 AM »
A fEARful can be modified to be biamped. I intend to get around to doing this one of these days.

crobbins

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Cabinets for biamping from an sf2
« Reply #8 on: March 25, 2011, 08:31:09 AM »
When I had my Seires one bass, I would come out of the small blue power supply, bass to one channel of F2B, treble to the other channel of F2B. From there it would go into each channel of my QSC power amp. After that, each channel into 4x10, of an Ampeg 810 cab(you can divide an 810 cab into two 410s). Sounded decent...

5sicks

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Cabinets for biamping from an sf2
« Reply #9 on: March 29, 2011, 10:41:16 AM »
If you run an amp directly to a HF driver (I'm talking compression type horn; not a paper coned speaker) the power and frequency bands must not be beyond the specs of the driver or you will fry it faster than a fly on a bug light. I guess I don't see any advantage to bi-amping (by-passing or modifying the crossover) a perfectly good full-frequency cab. If you are determined to bi-amp, obtain cabs that are specific to your application and tweak away...

Bradley Young

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Cabinets for biamping from an sf2
« Reply #10 on: April 15, 2011, 09:33:35 PM »
If you want to bi-amp, I'd suggest the fEarful designs by Greenboy (on Talkbass), or Bag End's INFRA systems if you're looking for something commercial.

cozmik_cowboy

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Cabinets for biamping from an sf2
« Reply #11 on: April 16, 2011, 07:31:24 AM »
Mebbe Hard Truckers - HT-215B (pretty self-explanatory) for the bottom and, depending on your tastes, JG-1, JG-3, or JG-4 (2, 3, or 4 12s, respectively, vertical arrangement) for tops.  Or AccuGroove - El Whappo 4-way on top & Whappo Grande 21 for the serious lows.
 
Peter
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tbrannon

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Cabinets for biamping from an sf2
« Reply #12 on: April 16, 2011, 09:45:10 AM »
Bradley,
 
I've been thinking about building a fEarful 15/6.  What cabinet are you playing through and are you running a power/pre setup through it?
 
I don't know if my question is relevant to the topic at hand, so if you feel better about emailing details, you can email to the details in my profile.  
 
Thanks-
Toby

edwin

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Cabinets for biamping from an sf2
« Reply #13 on: April 16, 2011, 10:27:43 AM »
I have a fEarful 15/6/1 and I will never play another type of cabinet again. The clarity and depth are beyond any other cabinet I've played through (which is a lot of them). It also provides a much more even sound around the rest of the stage than the other cabs I've used.
 
Preamp is either an F2b, Sarno Classic or Eden Navigator and power from a Crown XTi4000. I haven't gotten around to biamping yet.

tbrannon

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Cabinets for biamping from an sf2
« Reply #14 on: April 16, 2011, 11:12:35 AM »
Thanks Edwin.  I don't need much of a nudge to build one, but I think you guys are doing it anyhow.