Soundhound (or anyone who knows or works with professional gear)

Since you work with professional gear, what do you think of this amp?
http://www.proaudioreview.com/par/july03/carver_zr1600.shtml
It sells for around $830 and offers more power than any Outlaw amp. There seems to be a buzz about this product. Is this just a hype or a good deal? The reason I ask is that my new speakers (vmps rm40) want more power than 770 can deliver. I have one Adcom 555mkII and considering getting another one and use each bridged. The other solution is use this Carver at 700 X 2 (from a 30 lb chasis!)

In my opinion, digital amplifiers are not ready for prime time, and if absolute sonic quality is the goal, a good conventional power amplifier will sound better. Digital amplifiers are certainly going to be the technology of choice in the future, but this is not because they have the potential to sound better, but becasue they are cheaper to make. This can result in a "better sounding" ampilfier for the dollar, but not better sounding in the absolute sense when compared to a good conventional solid state or especially a tube amplifier.

The amp is using digital output stage to achieve this power to weight ratio and there is still controversy as to if digital is good enough quality to match analog. I looked at digital amps when considering what to get and found the reviews less than promising. When the 770 came out, I opted to use the 30day trial to test it and after seeing what it could do, I kept it and have been pleased ever since. I have used Carver, Crown, AB, Peavey and other high end amps in the past, all analog and they were all great amps. But for the professional market with a professional price to boot. I would suggest you purchase a model 200 and test it for the 30-day period. If your running ~400W into 4ohms and your set up in in a normal room environment, I cannot imagine you would need more power unless your room is extra large or your speakers efficiency is below 85. In any event, testing with one or two of the model 200's or even testing with the 770 for the trial period will help you understand if they meet your need. Lastly, with this Carver being a digital amp, I would recommend you hear it before you commit to buy. And I would not recommend long term 2ohm operation. We used 2 ohm configs for concerts, but it puts a lot of stress on the amps and they get much hotter than running 4ohm loads. We even tried 1ohm loads on the crowns and they worked (at they time crown was touting this could be done), but that amp was hot enough to fry an egg on. Heat shortens the life of electronics, especially semiconductor junctions which wear out faster with heat and caps that dry out sooner.

Ah, I see as I am writing this post that soundhound has comments about digital amps too which echo some of what I said earlier.

Thank you gentlemen for your replies. I suspected as much. I guess there is a point where "value for the money" crosses the low threshold of "absolute sound" and is no longer a bargain. I will stick with the conventional amps. So far I have tried using 2 channels of 770 and Adcom 555mk2, both of which are rated 300 into 4 ohms, on separate ocasions. I am just running the bass woofers (2 10" & a radiator) with these. ARC 100 (tube)for the mids/treble. Just like their passive subs, VMPS seems to want more power. It may just be a matter of tweaks and room arrangement, but the "concensus" on VMPS forum is that more power then 300 is required.

If it were the case, would M200 be more "powerful" than a channel of 770? Can you "bridge 2 M200's? I can bridge Adcom to get 600 into 4 ohms (I would need another one for the other speaker). The designer of these speakers is using Amzilla 2000 which is also rated the same 300 into 4 ohms but apparently with more current. I can't afford $5000 anyway. Would higher amparage offset less current and deliever "crisper" bass?

A model 200 would also have more power by virtue of it's independent power supply verses the shared power supply in the 770. The 200 cannot be easily used in bridged mode, however it can be done (almost any two identical amplifiers can be bridged) - just not by the consumer.

As far as current delivery - you only need enough current capability to deliver rated power output into the lowest impedance presented by the speaker. Amplifiers with more output transistors and larger power supplies will be able to deliver more current than other amplifiers.

[This message has been edited by soundhound (edited January 28, 2004).]

Thanks again, I have one more question.

One amp has 12 output devices per monobloc and is rated 400 amps into 4 ohms ( something like 10k microfarad filtering through each monobloc). It is driving the speakers with excellent result.

Another amp has say 6 output devices for stereo and is also rated 400 amps into 4 ohms. It is not, howerver doing the job.

If you bridge the second amp, you still only have 6 output devices but you now have ~800 amps into 4 ohms. Would this make a difference?

400 amps?? That's some healthy current - maybe you mean 40 amps?

Anyway, the amplifier with more output devices will with all other things being equal be able to pass more current than one with fewer output devices. Now the power supply may not be able to supply that current, but that is another issue! There are too many variables in an amplifier's design to make any specific judgements about the current capacity of any particular amplifier.

By the way, 10,000 microfarads is NOT very impressive - for a really stiff power supply, the capacitance shoud be at least three times that amount per supply rail.

Don't get too hung up on amplifier current specs. Manufactures rate their products using different testing methods, and unless you know specifically in what manner that current capacity is needed, there is no way to usefully compare between amps, or your need for "X" amount of current in the first place.

Soundhound,

I am not trying to get hung up on the numbers. What I am trying to find out is if a stereo amp (adcom 555mkII) that doesn't seem to have enough power for a particular pair of speakers can be bridged and work as a monoblock for 1 speaker (a second additional amp has to acquired for the other speaker)

I am trying to determine if I need a better and more expensive 2-channel amp (not affordable as of right now) or get a second identical, used, midfi amp (affordable) and bridge it for 600 watts into 4 ohms each.

By the way, in the previous post it should have been watts, not amps; and 100k, not 10k, microfarad per block.
Sorry about the mistake.

For what you want, true high current amps into a 4ohm load, I would steer you to some of the entry level pro-series amps, they will give you the power you want without paying the audiophile price for many of the other brands. Check out an amp like the QSC PLX1602 or PLX2402, partsexpress.com has the 2402 for $800 and it is rated 700W stereo into 4ohm. Balanced and 1/4" inputs, but you can get 1/4" to RCA adaptors really cheap if all you have is RCA. Or even the QSC RMX models which offer the same power but are a little cheaper. Or the Crown amps like the CE2000. Look on the pro-sound link on the right side of this page: http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=219

Yes, generally pro amps will have more current capability than any consumer amplifier. These amps must deal with difficult and heavy loads for prolonged periods without failing. This means they need lots of output devices, lots of heatsinking (and / or fan cooling) and a stiff power supply.

One potential downside of some pro amplifiers is their noise level (electronic and because of the fan), and that they are not necessairly designed to sound the best - their focus is more on reliability. There are good sounding pro amps out there, but I can't name them off the top of my head.