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Poweramp error (?!), help me please

dezspet

dezspet

Mar 21, 2007
249
3
Hungary
www.thecairoproject.com
#1
After several years of long hesitation, last week I have decided to buy a poweramp for my old, beloved Ampeg pre. Before that I have tried it on a rehearsal using my brand new EBS Reidmar's power section, and they were absolutely wonderfull together.
So I went to the Crown distributor and asked him about the XLS 1000, which based on the specs seemed to be the perfect choice: loud enough (I play clubs mainly), lightweight, good brand, clip limiter, bridge mode, etc.
So I went home to try my new set, and...
1. It just does not have enough volume.
2. In bridge mode it provides ther same volume !?!
3. It does have a bit higher volume when I use the XLR output of the Ampeg, but on gigs I supposed to use it for the PA.
4. And the overall sound, even if you take away the fact that it is not loud enough, is worse than a real bass amplifier's powersection.
I tried to change cables, did A B with the same cabinet (Bergantino) using my EBS, my MArkbass TA 503, and I think I carefully read and understood the manual about switching between modes.
So tell me, is that possible that a 150W/8 ohm EBS amp 5 times louder than a 700W/8 ohm (bridge) professional poweramp?
What do I miss?
:help:
Peter
 
#2
Just a wild guess:

The Drivecores have a very high input sensitivity, especially compared many effects return inputs on bass heads. Maybe your preamp does not supply enough juice to drive the power amp? Try to use the preamp output volume or gain or whatever to make the pre put out more...
 
#3
IMO, it really has nothing to do with the Crown but rather your preamp's (if you pre is an Ampeg SVP-CL) output. they have a very low output level and need a power amp with a more sensitive front end. the Crown's input sensitivity is 1.4V and you'd need one that is 0.775. i used to run an aphex 661between my SVP-CL and crown, not to use the compression but to boost it's output so that the amp was seeing enough level.
 
#8
Zooberwerx said:
Which brings up another question: given your bass, preamp, and power amp setup, can you even get the XLS 1000's signal indicator LEDs to light up?

Riis
Click to expand...
Yes, it lights up. When I put the volume up, almost to maximum on the Ampeg, it lights up quite close to clipping. In that position, when I put the level maximum on the Crown, I have a fair volume. But it's overdriven and there is no more headroom left. It's not a natural bass sound anymore.
Regarding bridge mode: I might be stupid, but do I have to use two cables or something like that? I just change the setting in the Crown to Bridge mono mode and leave my speakon cable in the same position.
 
#10
dezspet said:
Yes, it lights up. When I put the volume up, almost to maximum on the Ampeg, it lights up quite close to clipping. In that position, when I put the level maximum on the Crown, I have a fair volume. But it's overdriven and there is no more headroom left. It's not a natural bass sound anymore.
Regarding bridge mode: I might be stupid, but do I have to use two cables or something like that? I just change the setting in the Crown to Bridge mono mode and leave my speakon cable in the same position.
Click to expand...

No, you're not stupid....you've asked some valid questions. Please re-read the manual regarding the appropriate speaker cable type & configuration for bridged mono operation (I don't have the manual open at the moment). I'm highly suspicious that this is where your problem resides. Standard (mono / stereo) cables are wired +1, -1 at the amp end, bridged mono requires that the cables be wired +1, +2 at the amp end. The speaker end will remain +1, -1.

Riis
 
#13
Zooberwerx said:
No, you're not stupid....you've asked some valid questions. Please re-read the manual regarding the appropriate speaker cable type & configuration for bridged mono operation (I don't have the manual open at the moment). I'm highly suspicious that this is where your problem resides. Standard (mono / stereo) cables are wired +1, -1 at the amp end, bridged mono requires that the cables be wired +1, +2 at the amp end. The speaker end will remain +1, -1.

Riis
Click to expand...

I just checked the manual and you are damn right, I need a different cable for that.
But maybe I will go for a proper line level compressor first, if I get a stereo, for bigger gigs I can use two cabinets because the Ampeg has two outs.
Thanks guys for all the investigation and help!!
 
#16
It is your speakon cable! How do I know? I have spent the last few months wrestling with my Ampeg SVP-CL and Crown XLS1000. Either build or buy a biamp/bridge-wired speakon cable, plug it into the channel one output, and enjoy the roar!

The XLS1500 is even better.

BTW - I have one off the early, low-output SVP-CLs. I have been amazed at how much I can boost the input signal; these things have a ton of clean headroom. Try a line driver, like the CAE pedal, or some other clean boost.
 
#17
Primakurtz said:
It is your speakon cable! How do I know? I have spent the last few months wrestling with my Ampeg SVP-CL and Crown XLS1000. Either build or buy a biamp/bridge-wired speakon cable, plug it into the channel one output, and enjoy the roar!

The XLS1500 is even better.

BTW - I have one off the early, low-output SVP-CLs. I have been amazed at how much I can boost the input signal; these things have a ton of clean headroom. Try a line driver, like the CAE pedal, or some other clean boost.
Click to expand...

Thanks, I will do one!
 
#18
Given your earlier comments, I wouldn't even worry about boosting signal at this point. Instead, take care of either buying or fabricating a bridged cable and we'll see how far that takes you. If you're seeing a decent input signal at the amp without diming the preamp output and/or power amp attenuators, any line-level boost betweenst the two may be of little or no discernible value.

Riis
 

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