Can pro amps possibly sound good? Crown, QSC, etc


I have been looking into pro amps for a to-be-built HT/music room. Recently I came across an old review in The Stereo Times: The Complete Audiophile Magazine, which reviewed 2 discontinued Crown amps, the K2 and the Studio Reference I. The K2 the reviewer thought "not distinguished or especially musically refined", but the Studio Ref he thought an EXCELLENT full-range amp. It does have some amazing specs:

Signal-to-Noise (A-weighted) below rated full bandwidth power: 120 dB.
Damping Factor: >20,000 from 10 Hz to 400Hz.
780WPC into 8 ohms, 1160WPC into 4 ohms.

The review is here.

From what I've found so far, there are possbile downsides to using pro gear in an otherwise consumer setup, but in my case I think these are non-issues:

-fan noise: not an issue for me since I will have an equipment closet. Won't have to do a "fan mod".

-ugly: again, not an issue for me with an equipment closet

-hum: I believe not an issue as long as I use balanced interconnects from the prepro. Someone correct me if I'm wrong.

-expects pro-level input levels: I think not an issue if the amp has dip switches or gain controls?

And yet, over on a couple of AVS forum threads, I actually got asked to leave when I started suggesting pro amps. It seems as though some of the audiophiles there (and the same guys might be over here) don't even want to hear about a class of gear which imo just MIGHT sound good. It just isn't worth "polluting" an audiophile thread. Am I missing some other downside to pro amps, other than the above pints? Were these guys attitudes based on something substantive and audibly detectable, or just a form of audio bigotry?

I'm not saying all pro amps are going to be great (for instance I know the Behringer A500 is lousy), but might there be some good stuff too, like QSC DCA, or Crown Macro Reference (other suggestions would be welcome)?
syswei
Crown have been used to power main monitors in custom built studios for many years. If you are looking for dynamics then the power and headroom may come in handy in an HT setup. (Movies are not nearly as compressed as most music so dynamics/headroom is relatively more important. In studios where sound is live and uncompressed - the extra headroom can be critical)

What you will probably find is that at lower volumes the Crown will not be as refined as an audiophile amp - but at higher SPL it will seriously outperform an audiophile amp (in similar price range of course) For example, my power amp to the main speakers run in Class A until 2/3 power or up to around 150 watts, which is more typical of an audiophile design (performs better at low volumes).

The key consideration for any amp is to give it an EASY load. All to often difficult and complex speaker loads are the cause of major problems. Some speaker manufacurers seem to be competing today to actually give amplifiers difficult loads - due to the specifications game of bass extension and frequency response brochures (buyers often don't consider the load and speaker manufactuers like to just assume that you can find a perfect amplifier (and perfect amps do not exist)!
I have heard the Master series should be the most "Audiophile" sounding of the Crowns.. However I have heard some Standard QSC amps that are pretty good for way less money.. The K2 is a great amp for certain applications and is Fanless.. That’s the main Stigma of most PRo amps that they are Noisey from internal Fan cooling so watch out.. Also most do not have anything but 1/4 " and XLR pro connections on the back, so adapting them to run with your standard equipment can have its faults.. Beyond that many Pro amps take 4 volts to drive to Full power from a Preamp or source and many consumer or hi end players only put out 1 volt to 2 volts… Then you need a device between that’s made by companies like Rolls that can actually up your output signal by taking in a RCA and spitting out an XLR connection to the amp putting out the 4 volt conversion.

And Like the Crown K series I know that if you run them Single ended not Balanced they are only a 10 k impedance at the inputs, but if you can run balanced XLR without cheater plugs you will get a 20 k input impeadance which is much more universal, 10 k is pretty low for many Preamps to drive, especially if you use a Tube front end, so this can cause a limited bandwith and output as well in some cases..

In the end, if you can get a deal on a nice consumer grade amp go for it over all the extras sometimes needed to attempt the pro amp route, again the application and your situation will need to dictate whether its worth a try or not.. Some speakers might work well with pro sound and some not. That’s my opinion.
Not mentioned in your post is quite possibly the biggest reason pro amps are not desirable for a high performance home set-up. Pro amps are designed to be super reliable since they are often used by on-the-road musicians and thrown around from gig to gig. They are often overdriven, run in hot environments and operated less than ideal AC power. Therefore, the manufacturers design their products to be bomb proof and unfortunately, sound quality suffers because the parts they use are more reliability oriented and not necessarily chosen to be the best in terms of sonics - it's a trade off.
Pro amps are like everything else- some are good and some are bad. There are no issues with using them at home most of the time and often they can be had for far less than comporable audiophile jewelry.

I would not intentionally avoid pro stuff. I would just investigate residential use on a piece by piece basis.

-Rob
I use a Crown XLS-802D ($599.00 retail) to drive my living room and patio systems at home, and it sounds excellent, even though this series is often derided since it is made in China. It pumps out 800 wpc into 4 ohms, 500 wpc into 8 ohms. I run it off my Supratek Chenin tube preamp with no problems - the output of the Chenin is split so that half goes to the Crown and half to my main rig. In the living room it drives Magnepan MGMC1 speakers with a powered Monitor Audio R720 sub, and on the patio it drives KLH outdoor speakers and a passive subwoofer. It is driving all this through about 200 feet of CL3R in-wall cable and two Niles impedance-matching volume controls (set to 2X setting) and doesn't even break a sweat. Not quite the sound quality of my audiophile rig in the family room, but pretty darned close for the money.

It is built very solidly, with large heat sinks and a huge toroid. I think Crown has made several improvements to this series between the 802A and the 802D, and I am impressed by what I got for $599.00