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Whatcha think about "pro" amps from Crown, QSC, etc?

Scrappy

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It depends. Most pro amps nowadays are churned out in quantity from plants in Asia, and that is the major reason they can be so cheap. A byproduct of this is that parts quality is not necessarily top notch. These pro amps are not the same quality or as rugged as the pro amps of yore like the Crown DC150 which were made in the U.S., or ahem, ours.

There's nothing magic about these inexpensive pro amps - you still ultimately get what you pay for.
>Most pro amps nowadays are churned out in quantity from plants in Asia

Lab.Gruppen now assembles amps in Thailand instead of Sweden. Have only seen two amps with assembly mistakes yet (out of ~400)...
 

kipman725

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We own >10 QSC CX series amps which we use for PA they have only failed when VGA cables which short the dataport connectors where used on the dataports this apparently caused PSU failure. Looking at the dataport pinout there is a +15V aux supply out so probably that was shorted. The afflicted amps are all fixed and continue to work.
 

Mnyb

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So what about attenuation/gain control or clipping meters? Not good for consumers? Somewhat, but not particularly, significant differences in distortiion levels are an issue? Or is that more in relation to their power spectrum? I know you've mentioned you even prefer at home amps you guys don't design/make at work, too and just trying to get some expansion here on how specific aspects may affect even simple consumer use....
+1 as their is no real standard about levels .

But many hypex and purifi implementers does bring gain control/input sensitive adjustment with their offerings nowadays :) so at least this home market segment is implementing some of this . Clipping indicators ? I think some class-D modules supports that ? not sure who has them. But these commercial modules has all kind of protection.
(maybe the ruggedness and reliability is not up to pro use , hence why we don't see hypex all over the pro market ? )

benchmark have clipping indicator in their AHB2 .

I agree these are needed features all but absent in the old style hifi power amp of the past , with some exceptions . I once had an old GamuT amp with gain selections.
 

Sokel

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+1 as their is no real standard about levels .

But many hypex and purifi implementers does bring gain control/input sensitive adjustment with their offerings nowadays :) so at least this home market segment is implementing some of this . Clipping indicators ? I think some class-D modules supports that ?
Ice power Edge has everything you can imagine to show it's status,clipping is the last.And it's not the only ones I think,Hypex and Purifi has as well.


Check out the PDF.
 

rdenney

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With Purifi, the input gain is controlled by the "buffer"--really the first-stage amplifier. They come in various gain values, and some provide several choices. I think Buckeye, for example, is using an input buffer with several input gain choices for the Purifi amp.

Hypex is the same except for their all-in-one MP (mains-powered) models, which is what Buckeye sells. Those provide a single fixed gain of 25.5 dB. But the modules support clipping indicators whether or not the implementer makes use of the feature. Buckeye, for example, now uses a custom interface board that provides clipping indicators. Rick Sykora installed clipping indicators in my Buckeye NC502MP before it was shipped to me, and they are really nice to have.

Commercial amps also often have an input signal indicator, which I like. I've never seen that on a home amp. In the one commercial sound system I manage, the amp is not close at all to the control desk, and I sometimes use binoculars to check the indicators on the front of the amp, which is visible to me from about 50 feet away. If I'm trying to troubleshoot something during a church service, that is pretty useful information. But that is for a sound reinforcement system that works at a very subtle level, and even I can't always be sure the system is working. My goal was for people not to sense a PA system at all, but to be able to hear clearly. I'm not sure that feature is useful in the home environment where if the amp isn't working, silence ensues.

In a commercial amp, analog power meters seem to me to have precisely zero value, especially if the amp is supplied with signal and clipping indicators. But they sure do look nice in a home amp (even though they don't provide much useful information there, either).

Rick "all of whose commercial amps have input-gain controls on the front panel" Denney
 
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Commercial amps also often have an input signal indicator, which I like. I've never seen that on a home amp. In the one commercial sound system I manage, the amp is not close at all to the control desk, and I sometimes use binoculars to check the indicators on the front of the amp, which is visible to me from about 50 feet away.
Sounds like it might be time to move to some networked amps. ;)

It is quite nice to be able to see how your amps are doing on a FOH computer real-time (gain, headroom, limiting etc).

The newer amps from the "big three" tend to tell you if your boxes and individual drivers are happy as well, granted one of the big three only builds powered/active boxes, so that gives them an edge, and probably doesn't qualify for this discussion. :rolleyes:
 

rdenney

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Sounds like it might be time to move to some networked amps. ;)

It is quite nice to be able to see how your amps are doing on a FOH computer real-time (gain, headroom, limiting etc).

The newer amps from the "big three" tend to tell you if your boxes and individual drivers are happy as well, granted one of the big three only builds powered/active boxes, so that gives them an edge, and probably doesn't qualify for this discussion. :rolleyes:
I would at least like to network in the DSP EQ—a dbx PA2—which does support it. But this is an ultra low-cost system and it’s not my money I’m spending.

Rick “and no low-voltage wiring in the building” Denney
 

Scrappy

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Sounds like it might be time to move to some networked amps. ;)

It is quite nice to be able to see how your amps are doing on a FOH computer real-time (gain, headroom, limiting etc).

The newer amps from the "big three" tend to tell you if your boxes and individual drivers are happy as well, granted one of the big three only builds powered/active boxes, so that gives them an edge, and probably doesn't qualify for this discussion. :rolleyes:
I test a lot of PA amp systems. A newly-annoited System Engineer was hanging out when I was noising the rig. He mildly freaked out when he saw “load fault” flash everywhere. Well yea, all output connectors are open ha, load fault is a “good” indicator in that circumstance. Amps from Sweden, still with banana plugs
 

Holdt

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I like my old pro Yamaha P3200. It sounds better than Yamaha MX-630 / Yamaha RX-V3800. A comparison (not blind A/B) between the P3200 and Yamaha A-S1000 is undeterminable until the volume gets high, then the pro amp is keeping the sound much more clean. Some distortion must be present at higher SPL on the A-S1000.
My speakers have 7 drivers each, though small in diameter. The sensitivity is 90 [email protected] m. but I have a suspicion that it's a great deal lower than that. They can take a lot of power.

I think the Yamaha P3200 is quite classy to look at. This picture is an old one where I had the top cover lifted a bit with washers and deactivated the always-on fans. Now it's completely surface mounted again and the fans wired in series to lower the noise to near-silent level.

To get comparable power, quality and dampening factor, I would have to invest some serious money.
5.JPG
 
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