• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Power Amp Help.....

kenny ames

kenny ames

Nov 27, 2002
905
1,413
Nashville, TN.
#1
Have been running my Aguilar DB680 pre into the power section of an older Trace Elliott AH500 Series Six head. Decided to try and lighten the load a bit and got a Crown XLS1500. Class D light power amp. Long and short was very underwhelmed w/ the sound of the Crown compared to the power of the Trace. Was lacking the fundamental of the Trace. Guess you cant have you're cake and eat it too. Trying to find a power amp that will deliver the oomph of the power section from the Trace but not be more than 25-30 lbs. Any thoughts?? LOVE the DB680 and would like to find something thats going to make it shine. Resigning myself to a heavier (but not too heavy) power amp. Thanks guys.

And please dont flame me. Know there are many threads asking about a good power amp. Have looked at many already. But went off of favorable reviews regarding the Crown when I purchased it. :-) Thanks!
 
#2
Are you talking about less volume or a tonal difference? If its volume its very likely you are not giving the Crown enough juice. If you stick some kind of booster in your signal chain (like an Art Tube MP for example) I bet big you'd get the power your Crown seems to be lacking.

When matching pres and power amps you have to match the input sensitivity of the power amp to the output of the pre.
 
#4
Tonal difference. Had run master volume on the DB680 considerably higher to achieve the same volume as the Trace. The Crown was bridged and both channels were wide open. Best way I could describe it was Crown sounded more digital and the Trace was more analog. Thanks for your input.
 
#9
kenny ames said:
Tonal difference. Had run master volume on the DB680 considerably higher to achieve the same volume as the Trace. The Crown was bridged and both channels were wide open. Best way I could describe it was Crown sounded more digital and the Trace was more analog. Thanks for your input.
Click to expand...

In bridged mono mode, only use the channel 1 attenuator. Channel 2 should be turned fully CCW. The Crown's display should also read "Bridge / Bypass" indicating that the selectable HPF has been defeated.

Did you cable the pre / power connection XLR > XLR or 1/4" > 1/4"?

Don't forget to use a bridge speaker cable (+1, +2) on the Crown's channel 1 speaker output. BTW, the stupid things are flip-flopped...channel 1 / A sits to the right of channel 2 / B

Riis
 
#11
+1 to input sensitivity making a difference.

My Aggie pre of choice is the DB659, and one of my favorite matches for that pre is a Carvin DCM 1000 (the old DCM series, not the DCM-L).

Another option is to run a parametric eq b/w the Aggie and the power amp. This allows you to set the preamp for the best consistent FOH feed via post-eq DI. (the Aggie becomes set-and-forget from stage-to-stage, and the outboard parametric is where you make tweaks for the anomalies of any particular stage). The outboard parametric also gives you an additional gain stage to match relatively low output pres with a wider range of power amps.

That solution might seem more obvious with the DB659 than the DB680 (which after all has the more extensive eq and is a 2-space unit). However, the benefits are the same. The extra eq on the 680 just lets you send a more precisely sculpted DI feed to FOH.
 
#13
I'll echo what was said about the cable. You may need to rewire a speakon speaker cable to get the full power output in bridge mode. If you're just using a standard cable you may only be getting the 1-channel power output. This happened to me when I first went to a pre-power setup.
 
#14
Judging by the comments, it's clear that many here don't know that this amp doesn't have an input sensitivity "switch" and that it has crossover, limiter and other capabilities/needed settings.

My advice to the OP- read the manual and try different settings. If you wanted a simple amp, why did you buy this?
 
#15
Thanks guys for the heart felt replies. Appreciate the time and energy in your responses. Have some free time later today and will check how Im running the Crown. Do believe it is "bridge/bypass". 1/4 to 1/4 for the pre to power connection. Will give the Crown another shot.

To answer '58Bassman.....I bought because I got into it at a good price, the weight was appealing and the Crown name is reputable. Thx for your reply.
 
#17
The Crest CA series is an absolute beast of an amp, in tone, weight, and size. It's a full amp depth, so you'd need a full sized rack to house it. Just something to keep in mind because it will drive the weight up considerably.

I have a CA4 right now, but I never use it outside of the house or practice where it can get parked for extended periods.
 
#18
kenny ames said:
Tonal difference. Had run master volume on the DB680 considerably higher to achieve the same volume as the Trace. The Crown was bridged and both channels were wide open. Best way I could describe it was Crown sounded more digital and the Trace was more analog. Thanks for your input.
Click to expand...

volume knobs aren't calibrated. Some get their maxed output in the first quarter turn. Some actually keep working through the whole range. Crown's input sensitivity is based on FOH industry standards. You db680 and your trace are probably not.

Follow the advise above about boosting the signal a little more to the crown.

Things that are louder sound better. It again is probably that the trace is playing louder, boost the crown, and it will clear up.

Or get a power amp with a DSP and you'll be able to fully adjust the sensitivity. It will be more complex. But it would be more versatile than experimenting with a bunch of amps until you find the right sensitivity for your pre-amp.
 

Latest posts

Top Bottom
Back