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robertbartsch
10-11-2008, 06:12 AM
What commercial units are available that have:

1. two-way varaible Hz controls
2. RCA input/output jacks
3. Frequency response 20-20,000
4. 120 volt power

scott fitlin
10-11-2008, 10:12 AM
Check out MARCHAND.

www.marchandelec.com

4313B
10-11-2008, 10:16 AM
I didn't know Marchand offered variable crossover frequencies on the fly. I thought they were card based? I could be wrong.

The Rane SAC 22 is variable but one would need to adapt it to RCA inputs/outputs.

http://www.rane.com/note110.html

http://www.rane.com/note151.html

I don't know if Rane gear sounds any good. I figure it must be ok since Greg uses some kind of Rane with the best components available from JBL. :dont-know

Mr. Widget
10-11-2008, 11:03 AM
I don't know if Rane gear sounds any good.I don't know about this newer series... the older stuff, the AC series, are pretty rough sounding. I found them perfectly acceptable in my HT system, but for really critical listening in my 2-channel room... not even close.


Widget

boputnam
10-11-2008, 03:36 PM
2. RCA input/output jacksRobert...

IIRC, your amp, at least one of them, has balanced inputs? Why not adapt the pre-amp output, and be done with the RCA's...?

AVCables (http://www.avcable.com/) is one of my favorite sources for all sorts of stuff - best quality and good prices. They have all sorts of adapters. You should bookmark their site! :)

Here's their selection of female RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-FEMALE).

Here's their selection of male RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-MALE).

macaroonie
10-11-2008, 03:40 PM
DBX have 4 analog X/O 2 way and 3 way with either rca or xlr . 24 dB LR circuits.

boputnam
10-11-2008, 04:05 PM
DBX have 4 analog X/O 2 way and 3 way with either rca or xlr...Really? I only know of their versions with TRS jacks (and the others with XLR). Do you have a model number?

macaroonie
10-11-2008, 05:51 PM
Brain fade. :(:o:

scott fitlin
10-11-2008, 10:57 PM
I didn't know Marchand offered variable crossover frequencies on the fly. I thought they were card based? I could be wrong.

The Rane SAC 22 is variable but one would need to adapt it to RCA inputs/outputs.

http://www.rane.com/note110.html

http://www.rane.com/note151.html

I don't know if Rane gear sounds any good. I figure it must be ok since Greg uses some kind of Rane with the best components available from JBL. :dont-knowPhil will build to suit your needs/wants.

Custom exotica, or standard units.

HIS stuff sounds GOOD and is fairly priced.

grumpy
10-13-2008, 08:09 AM
Really? I only know of their versions with TRS jacks (and the others with XLR). Do you have a model number?

they add an XL to the end, e.g., dbx223 -> dbx223xl

http://www.dbxpro.com/223XL/223XLspecs.php :)

4313B
10-13-2008, 09:19 AM
Phil will build to suit your needs/wants.

Custom exotica, or standard units.

HIS stuff sounds GOOD and is fairly priced.Yeah, the Marchand units make sense to me once the correct crossover frequencies and slopes have been determined for whatever DIY project is going on at the time.

robertbartsch
10-14-2008, 04:52 PM
..so the DBX 223Xl unit has variable frequencies and uses 3-pin inputs and outputs?

4313B
10-14-2008, 05:03 PM
..so the DBX 223Xl unit has variable frequencies and uses 3-pin inputs and outputs?Here's the manual -> dbx 223XL (ftp://ftp.dbxpro.com/pub/PDFs/Manuals/English/dbx223234XLManualA2.pdf)

boputnam
10-15-2008, 05:22 PM
they add an XL to the end, e.g., dbx223 -> dbx223xl ...:)Uh, yes, I know that, Dave.

My quote, above, was questioning macaroonie's post that dbx offered an RCA version - they do not.

But, you have to read the thread to follow it. ;)

Anyway...

scott fitlin
10-15-2008, 07:56 PM
Marchand can make variable xover point control. and he DOES OFFER BOTH RCA, or XLR, bal or unbal, u choose.

grumpy
10-16-2008, 10:54 AM
Uh, yes, I know that, Dave

Doh... read the thread... just too quickly. :o:
At least robertbartch got something out of it.

robertbartsch
10-17-2008, 05:28 PM
BOPUTNAM:

So, if I use the xls/rca cable connector adaptor any balanced output/input will become an unbalanced input/output; right?

What exactly is the benefit of balanced input/outputs?



***********************

...

IIRC, your amp, at least one of them, has balanced inputs? Why not adapt the pre-amp output, and be done with the RCA's...?

AVCables (http://www.avcable.com/) is one of my favorite sources for all sorts of stuff - best quality and good prices. They have all sorts of adapters. You should bookmark their site! :)

Here's their selection of female RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-FEMALE).

Here's their selection of male RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-MALE).
__________________
bo

Ian Mackenzie
10-17-2008, 06:25 PM
BOPUTNAM:

So, if I use the xls/rca cable connector adaptor any balanced output/input will become an unbalanced input/output; right?

What exactly is the benefit of balanced input/outputs?



***********************

...

IIRC, your amp, at least one of them, has balanced inputs? Why not adapt the pre-amp output, and be done with the RCA's...?

AVCables (http://www.avcable.com/) is one of my favorite sources for all sorts of stuff - best quality and good prices. They have all sorts of adapters. You should bookmark their site! :)

Here's their selection of female RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-FEMALE).

Here's their selection of male RCA adapters (http://www.avcable.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=RCA-ADAPTER-MALE).
__________________
bo

The benefit is common mode noise rejection over distance particularly low level signals like Mics feeding a desk. The problem is most active crossovers in the Pro sene usually if balanced jacks or XL connectors.

For domestic audio this is no benefit really for short cable runs and the additional balanced circuits can deteriorate the otherwise HiFi signal.

Balanced cables to not eliminate earth loops. Not all equipment offers true balanced operation either and some of the JBL electronics do not follow convention. So beware.

Normally the balanced to unbalanced output runs the hot pin (2) to the centre RCA and shield pin (1) to the outer sleeve of the RCA. Pin (3) is left floating.

Nornally unbalanced RCA to a balanced input has hot centre to pin (2) and the outer sleeve to pin (1). Pin (3) on the balanced input should be shorted to pin (1) to reduce noise.

jblbgw_man
10-18-2008, 12:32 AM
Normally the balanced to unbalanced output runs the hot pin (2) to the centre RCA and shield pin (1) to the outer sleeve of the RCA. Pin (3) is left floating.

Nornally unbalanced RCA to a balanced input has hot centre to pin (2) and the outer sleeve to pin (1). Pin (3) on the balanced input should be shorted to pin (1) to reduce noise.

An additional variation of this is the servo balanced outputs where pin 2 (Hot +) goes to the center pin of the RCA and pin 3 (Cold -) (not pin 1) goes to the earth of the RCA, therefore isolating the groung from the source equipment ;)

robertbartsch
10-21-2008, 08:48 AM
I purchased a used DBX 223XL from Flee-Bay and I hope to use it in a two-way - bi-amp system.

My Denon 3300 receiver has pre-amp "out" and power amp "in" RCA cable jacks. My low freq amp will be a 200 watt per channel Adcom and I plan to use the Denon power amp (100 watts) that is built into the receiver as the high freq. amp.

So basically, the electronic crossover goes in between the single pre amp "out" jacks and the dual (twin) power amp "in" jacks; right?

Apparently, my 2 inch HF compression driver (JBL 2445) has a tendancy to roll off the HF material above 10HK, so will the DBX allow me to boost the material above this freq?

Thanks...

jblbgw_man
10-22-2008, 09:04 PM
I purchased a used DBX 223XL from Flee-Bay and I hope to use it in a two-way - bi-amp system.

My Denon 3300 receiver has pre-amp "out" and power amp "in" RCA cable jacks. My low freq amp will be a 200 watt per channel Adcom and I plan to use the Denon power amp (100 watts) that is built into the receiver as the high freq. amp.

So basically, the electronic crossover goes in between the single pre amp "out" jacks and the dual (twin) power amp "in" jacks; right?

Apparently, my 2 inch HF compression driver (JBL 2445) has a tendancy to roll off the HF material above 10HK, so will the DBX allow me to boost the material above this freq?

Thanks...
Essentially YES .... but remember that your Dennon output level will be nominally -10dBu where as the nominal operating level of the 223XL is +4dBu, this may present as a higher than anticipated noise floor level from the 223XL as you will be operating typically 14 dB below the nominal operating level, therfore resulting in a 14dB lesser S/N figure than that that is published for this unit, so around -80dB instead of -94dB :(


These units are normal polarity convention so pin 2 is Hot + and pin 3 is Cold -. Using 2 conductor shielded cable, on the input to the 223XL connect the + of the RCA to pin 2 of the XLR and the RCA ground to pin 3 of the XLR, connect the shield of the cable to pin 3 of the XLR but do not connect it to the Dennon, leave it unterminated at the Dennon end. On the output of the 223XL take pin 2 to the RCA + centre pin, As I don’t believe the 223XL are servo balanced outputs, therefore connect the negative of the RCA to pin 3 of the XLR …… hey presto it should work with a good chance you won’t end up with a ground loop. :applaud:

Now ……… Do we presume you are still using some sort of passive network feeding the 2445 to provide CD equalisation??? :blink:

I will be interested in your thoughts of the 223XL …………. I found them to be rather harsh sounding beasts especially feeding a compression driver. I don't believe their design is high end at all.