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louped garouv
08-16-2004, 02:23 PM
so I have altec 19s, altec 1590C amps (2) and white 4400 EQs (2); the cables out of my mixer (Rane rotary or Bozak) are either XLR or RCA -- is it a simple matter of stripping the connector from one end of the cable to get it connected to the terminal strip connector of the amps? can I run both amps and EQs to run two channels?

right now I am running the 19s with a 1962 Heathkit AA151 (28 tube amps - 14 per channel), and I am unsure of how to hook up a system with terminal strips.... Also don't want to blow up my 19s

Also is it considered preferable to run from mixer to eq to amp to speaker?

thanks for all of the help.

boputnam
08-16-2004, 06:12 PM
Originally posted by louped garouv
... is it considered preferable to run from mixer to eq to amp to speaker? :yes: The only way.

I'm confused by your first part, but maybe...

1) Come out of the "mixer" - if you can, use the XLR balanced (strip it) and connect to the White barrier strip accordingly. Use shielded cable between. You might want to experiment with dropping Pin1 AT THE 4400 if you get a groundloop.

2) Come OUT of one EQ - use it's barrier strips - connect to one channel of the amp. (altec 1590C is stereo, 200w, right?)

3) Do this identically for each channel, L and R (one EQ for each channel).

4) I think you have an extra altec 1590C...

louped garouv
08-16-2004, 06:41 PM
thank you very much for the information regarding the stereo nature of my amps, i am glad to hear it as i am always glad to have extras around....:banghead: although i should investigate stuff like this first....

seems easy enough, and sorry for the confusion,

thanks...

boputnam
08-16-2004, 07:05 PM
Ha!

Well, rest assured if anyone even thinks I erred, they'll be all over it! ;)

scott fitlin
08-16-2004, 09:50 PM
1) Come out of the "mixer" - if you can, use the XLR balanced (strip it) and connect to the White barrier strip accordingly. Use shielded cable between. You might want to experiment with dropping Pin1 AT THE 4400 if you get a groundloop.

This is how I do it, and I actually find dropping pin 1 ground sounds better, maybe its just me! I use White 4200,s and I connect the outputs of my mixer to Pin 3 + and Pin 2 - and have no problems whatsoever!

:cool:

louped garouv
08-17-2004, 07:22 AM
thanks for all the help -- man these 19s are growling now and the treble freqs aren't screaming at me anymore....

thanks again for all of the help......

boputnam
08-17-2004, 07:35 AM
PAYBACK TIME!!!

Can you post some pics...? :yes:

louped garouv
08-17-2004, 08:04 AM
as soon as I take some pictures and have them developed, yes....

i need to get a digital camera...

louped garouv
09-22-2005, 11:02 PM
PAYBACK TIME!!!

Can you post some pics...? :yes:

here they are...

And right now -- I have the Turntables/CD players to UREI 1620 PreAMP.. in the FX loop, I have the Whites hooked up... then to a Hafler DH500 to A7s (802G/511B loaded)

working on getting the boxes built for my TAD subs... then i will run the signal thru the RLA X2000 Crossover pictured... and end up with: < 100Hz to subs; 20Hz - 800Hz to 511B; 800Hz - 20KHz to 802G; >= 7KHz to JBL 075

fun fun fun..... thanks a bunch for the help over the last year or so...

Mike Caldwell
09-23-2005, 06:35 AM
Hello

The Urie mixer you have is about to be reissued from Soundcraft. They are much
sought after in the DJ world and I guess Harmon (Soundcraft, JBL, Urie and more) took notice. I could think of a few other items they should to reissue.
If you can find them you can get crossovers to plug into your white EQ's. Do you have any specs of the crossover you have now, frequency, cut off slope.
My guess if it was built in the 70's it will a 12db at best maybe 18db cut off slope. There are many thoughts on what cut off slope 12, 18, 24, 48 and what the filter types that sound best. For higher power applications the steeper slope will give you better driver protection and less comb filtering from haveing less frequecny overlap between drivers.
Looking at where you want to crossover you would need a 3 way stereo crossover unless you are going to go passive into the 075's. I would also not try to over lap the sub cabinets with your Altec 19's. Many times when you have different speakers and cabinet designs operating in the same range of frequencies in the same sound system they can tend to cancel each other out in different places.
If you sub will be a 18 inch I would crossover at 80hz (sub to Altec 19)
The 19's crossed over into the horns at 1200hz with their internal passive crossovers. If your going to make the system all active I would that same crossover frequency.

I would also make sure you have a high pass filter in the system at about 35hz to reduce any turntable/record mechanical vibration and if your doing a show, vibration from people dancing. That wil give you more amp headroom from not wasting power trying to amplify a 20hz signal or lower and it will help save your speakers from trying to reproduce that signal.

Mike Caldwell

louped garouv
09-23-2005, 06:56 AM
Hello

The Urie mixer you have is about to be reissued from Soundcraft. They are much
sought after in the DJ world and I guess Harmon (Soundcraft, JBL, Urie and more) took notice. I could think of a few other items they should to reissue.

done, released and the units are said to be good -- still waiting to hear a 'real' head to head review... but overall ppl seem to be happy with the reissue -- Scotty has one... Mine is especially sought after due to the modifications/work done on it by RLA...



If you can find them you can get crossovers to plug into your white EQ's. Do you have any specs of the crossover you have now, frequency, cut off slope.
My guess if it was built in the 70's it will a 12db at best maybe 18db cut off slope. There are many thoughts on what cut off slope 12, 18, 24, 48 and what the filter types that sound best. For higher power applications the steeper slope will give you better driver protection and less comb filtering from haveing less frequecny overlap between drivers.
Looking at where you want to crossover you would need a 3 way stereo crossover unless you are going to go passive into the 075's. I would also not try to over lap the sub cabinets with your Altec 19's. Many times when you have different speakers and cabinet designs operating in the same range of frequencies in the same sound system they can tend to cancel each other out in different places.
If you sub will be a 18 inch I would crossover at 80hz (sub to Altec 19)
The 19's crossed over into the horns at 1200hz with their internal passive crossovers. If your going to make the system all active I would that same crossover frequency.

I did look into getting the Xover modules from White, but the boss was on vacation and the worker bee didn't know which of the plug-in modules they could not make -- from what I could gather; evidently the 4400s are being discontinued due to a lack of available parts for some of the modules, not the EQ itself....


the RLA X2000 crossover is 18db Butterworth stereo design. the crossover points (as listed above; with the overlap) are the desired parameters for a vintage disco-style soundsystem redroduction -- not necessarliy Hi-Fi world stuff here. Maybe Scott can give us the low down on why/how these point came into being (besides Al and Richard decided they would be the best points for the X2000 design.....)



I would also make sure you have a high pass filter in the system at about 35hz to reduce any turntable/record mechanical vibration and if your doing a show, vibration from people dancing. That wil give you more amp headroom from not wasting power trying to amplify a 20hz signal or lower and it will help save your speakers from trying to reproduce that signal.

Mike Caldwell

Right now, when needed -- and not in right at this time, I am using the tuna can method -- basically you take empty tuna cans (12 in my case) and secure strong rubberbands around the outside of them -- them set your TT on top... this is a very low tech, old school NYC method for TT isolation... there are more hi-tech versions, but I am cheap on certain things and the tuna cans seem to work very well as long as you replace the rubberbands on occasion -- but the idea is the same....

I posted that here before, will try to find the thread....
found it...
http://www.audioheritage.org/vbulletin/showthread.php?t=5773&highlight=isolation

scott fitlin
09-23-2005, 08:44 AM
:yes: The only way.

I'm confused by your first part, but maybe...

1) Come out of the "mixer" - if you can, use the XLR balanced (strip it) and connect to the White barrier strip accordingly. Use shielded cable between. You might want to experiment with dropping Pin1 AT THE 4400 if you get a groundloop.

2) Come OUT of one EQ - use it's barrier strips - connect to one channel of the amp. (altec 1590C is stereo, 200w, right?)

3) Do this identically for each channel, L and R (one EQ for each channel).

4) I think you have an extra altec 1590C...Everything he said!

Its the only way, mixer to EQ to crossover or amps, whatever your setup has!

I drop Pin 1 and leave it open, been doing since the 70,s! You should have no problem!

Mike Caldwell
09-23-2005, 08:44 AM
Hello
I was talking about an active electronic filter with a 35hz 18 or 24 db cut off slope. Isolating the tuntable mechanically from the floor, table ect helps but there is still a lot very low frequency noise coming from irregularities on the surface of the record. In a system with no high pass filtering watch the cone of a woofer while playing the silent cuts between songs and you will see the cone drifting back and forth some at just a moderate volume setting let alone what it is like at show volumes.

Mike Caldwell

scott fitlin
09-23-2005, 09:41 AM
done, released and the units are said to be good -- still waiting to hear a 'real' head to head review... but overall ppl seem to be happy with the reissue -- Scotty has one... Mine is especially sought after due to the modifications/work done on it by RLA... __________________________________________________ ________________


You just hold on to that vintage urei, and dont worry about the new one! It hasnt anything over the old one sonically, it sounds like a urei, but a wee bit different! They used " El Cheapo " 1% metal fim resistors throughout, and this is where the cleaner, but thinner and somewhat different sounding midrange comes from, as well as different IC,s and caps! The NEW urei sounds like a urei, but is thinner sounding in the low end, and has a sterile sound to the midrange! STICK WITH WHAT YOU GOT!

__________________________________________________ ________________





the RLA X2000 crossover is 18db Butterworth stereo design. the crossover points (as listed above; with the overlap) are the desired parameters for a vintage disco-style soundsystem redroduction -- not necessarliy Hi-Fi world stuff here. Maybe Scott can give us the low down on why/how these point came into being (besides Al and Richard decided they would be the best points for the X2000 design.....)>>>>>>>>>>

My reply,


80hz was always considered a technically correct subwoofer xover point, but true subwoofers dont have THAT huge KICK we want in a dance club! 100hz, 18db gives you a bit of that upper bass kick, and makes dance music come to life! There was even an article by Siegfried Linkwitz some time back, stating that 100hz is the best subwoofer xover point!

Same thing basically for the tweeters! Dance music wants a bit of that sizzle! Cross over your super tweeters at 8K or higher, depending on your tweeter and you dont hear the Tss, tss tss! It becomes all air and harmonics at what is considered proper crossover points! Dance systems tend to exaggerate the sound a bit, but if done properly, can sound very real, and very " BIG " ! And there aint nuthin like a JBL tweeter for this job!



Read the above!

scott fitlin
09-23-2005, 09:44 AM
Hello
I was talking about an active electronic filter with a 35hz 18 or 24 db cut off slope. Isolating the tuntable mechanically from the floor, table ect helps but there is still a lot very low frequency noise coming from irregularities on the surface of the record. In a system with no high pass filtering watch the cone of a woofer while playing the silent cuts between songs and you will see the cone drifting back and forth some at just a moderate volume setting let alone what it is like at show volumes.

Mike CaldwellThe RLA crossover he has, does in fact have a subsonic filter. So rumble, record warps, and other extraneous VLF vibration are filtered! There are also variable HP and LP filters on the White 4400,s, Louped can set the LF filter from flat to 160Hz! So, you can set the LF filter to 30 or 35hz, and this will work. The RLA has its subsonic filter set to 20HZ, 12db, so using the filter in the White EQ,s becomes additive!

Oh, and I almost forgot, when the RLA,s middle knob and output is set up as full range, it has bandpass characteristics, its designed with a LF and HF roll off, built in, at the manufacturers predetermined frequency points.

louped garouv
09-23-2005, 10:29 AM
I NEVER was considering getting rid of my UREI, really solid mixer and in really really good shape.... was just considering another for backup -- I guess I will wait for the great condition, original Bozak to wander my way instead of ponying up for a 1620LE... I guess its kinda like the RLA X3000 vs. RLA/RANE X3000a -- same species but a completely different animal still....

I am actually running the EQs through my FX loop on the UREI -- haven't tried it externally run yet, but i am all rigged up for easy swapping now.... :bouncy: A/B testing will surely be in the near future, I have the filters set flat right now, I have just recently begun really playing with the Whites -- testing and listening to both A7s and Model 19s through balanced and unbalanced connections -- still learning to unlock the full potential of my components together... quite a joyous learning experience really. It is amazing how much difference a piece of equipment in or out of the chain, or how you run your lines, can make in the ultimate system reproduction qualities.


gotta say thanks again to all the forum members for the insights they have given to the forum over the year(s)....


Scott -- is it common to see the X2000s with the full out modification? Is that an easily reversible mod? what would that do to the collectability of the unit?

scott fitlin
09-23-2005, 11:12 AM
When you send your unit to Al, tell him you want the middle section as full range, with bandpass characteristics. On the 2000 I dont think it will hurt the value as Al designed and built them for Richard! I have seen some x-2000 set up as three way, most as 4 way crossovers, though!

The 3400, i.e. the X-4000 or X-3000 is an easy change to 3 or 4 way operation. On the 2000 its a little different. But the X-4000 and 3000 are the same board, some jobs had the full range to a second crossover, others had it as a 4 way. The board in the 2000 is physically smaller than the 3000/4000 but its the same circuit! Just different layout.

scott fitlin
09-23-2005, 11:14 AM
I am actually running the EQs through my FX loop on the UREI -- haven't tried it externally run yet, but i am all rigged up for easy swapping now.... :bouncy: A/B testing will surely be in the near future, I have the filters set flat right now, I have just recently begun really playing with the Whites -- testing and listening to both A7s and Model 19s through balanced and unbalanced connections -- still learning to unlock the full potential of my components together... quite a joyous learning experience really. It is amazing how much difference a piece of equipment in or out of the chain, or how you run your lines, can make in the ultimate system reproduction qualities.


You can run the EQ,s this way, but I still prefer the mixers outputs feeding the EQ,s.

What differences do you hear between balanced and unbalanced, if any?

louped garouv
09-23-2005, 11:23 AM
I tell you -- I really think running unbalanced opens things up a bit -- highs seem to go higher and lows seem deeper... It's really hard to put your finger on, but the sound definately changes.... almost like there is a slight constriction/compression to the signal when using the balanced outputs

I need to start a notebook keeping notes of my impressions of different gear....


I like the A7s alot better running unbalanced w/ Phase Linear 100W/ch instead of balanced w/EV 7300a 300W/ch -- could be the different amp's sound tho' -- I need to come up with a better way to compare apples to apples....

I am going to pick up some more amps soon (JBL/UREI 6260s), they should make even swap comparisons a little easier than my set up currently allows easily...
I'll report back.

scott fitlin
09-23-2005, 11:39 AM
I tell you -- I really think running unbalanced opens things up a bit -- highs seem to go higher and lows seem deeper... It's really hard to put your finger on, but the sound definately changes.... almost like there is a slight constriction/compression to the signal when using the balanced outputs


I like the A7s alot better running unbalanced w/ Phase Linear 100W/ch instead of balanced w/EV 7300a 300W/ch -- could be the different amp's sound tho' -- I need to come up with a better way to compare apples to apples....

I am going to pick up some more amps soon (JBL/UREI 6260s), they should make even swap comparisons a little easier than my set up currently allows easily...
I'll report back.Pretty much what I hear too!

To me, the mids and highs, when going balanced with the urei and white, tends to sound a bit harsh. Yet, going unbalanced the sound opens up, becomes smoother, more involving, and I seem to hear very minute details in the music.

I have also found that the Altec cabinets with appropriate Altec woofers seems to favor older lower powered amps!

louped garouv
09-23-2005, 11:46 AM
good to know I'm not going crazy....


I have some musician friends that also favor vintage, lower powered rigs to the 'clean' new stuff -- granted they mostly play blues / old rock and most of what they are concerned with is the tone..... those vintage guitars are sweet -- my firend brought up a '71 Les Paul '50s reissue in near mint condition, its just sweeeeeet

Earl K
09-23-2005, 12:02 PM
It's really hard to put your finger on, but the sound definately changes.... almost like there is a slight constriction/compression to the signal when using the balanced outputs

Yeh,, it's worth noting , balancing is a noise reduction topology, not a topology designed to increase bandwidth and resolution , per se. Though with exteme noise contamination to a signal, resolution and bandwidth do become secondary concerns. Unbalancing circuits when done through chips are the worst offenders for giving this feeling of a slight constriction or compression. Discrete front-ends ( and their debalancing networks ) are better at avoiding this . Anyways , that's my experience .


:p

scott fitlin
09-23-2005, 12:05 PM
Yeh,, it's worth noting , balancing is a noise reduction topology, not a topology designed to increase bandwidth and resolution , per se. Though with exteme noise contamination to a signal, resolution and bandwidth do become secondary concerns. Unbalancing circuits when done through chips are the worst offenders for giving this feeling of a slight constriction or compression. Discrete front-ends ( and their debalancing networks ) are better at avoiding this . Anyways , that's my experience .


:pThe urei 1620 does use an IC as a phase splitter, to take the single ended signal, and create the + and - signals for the balanced ouput!

But the house outs are transfomer balanced, not active balanced differential.