Crown Monster Amps vs Audiophile Monster Amps

[whoaru99]

I'll post a video of the Macrotech racks as a show next time.....they absolutely can and do run sustained high levels at full power, often in current limiting mode as well....
You'd never do that at home, but occasionally when I have run my system up to extreme levels, the load indicator does light up which indicates you are starting to draw significant current...
Good luck blowing my speakers up!!

Not normally, anyway. I occasionally run mine up to the occasional flicker of clipping indicator, but that's pretty rare.

Crown documents that sort of thing nicely.

Their data for MA5000VZ shows about 12A @ 120 and about 19A @ 120 running 8 ohms and 4 ohms, respectively, at full tilt with 30% duty cycle (which they state is roughly what you see with hard rock music).

No doubt that is quite a lot more than the typical home amp draws, but it is not absurdly high amount to contend with.

 

[kevzep]

Not normally, anyway. I occasionally run mine up to the occasional flicker of clipping indicator, but that's pretty rare.

Crown documents that sort of thing nicely.

Their data for MA5000VZ shows about 12A @ 120 and about 19A @ 120 running 8 ohms and 4 ohms, respectively, at full tilt with 30% duty cycle (which they state is roughly what you see with hard rock music).

No doubt that is quite a lot more than the typical home amp draws, but it is not absurdly high amount to contend with.

I run my entire system off a 16amp service, never tripped the breaker, would be very unlikely I would...

When I do a thermal test on these amplifiers, its not a single sine wave, its a composite waveform which if you listen to it, sounds like a machine gun with a growling and low multiple wave type noise going, its horrific and loads the amplifier nicely, running this into the amp on a 2.7Ω load both channels, it will reach thermal limit in 5-7mins, you can see the waveform truncated at the output, this is the condition it will draw 13.4 amps.
There are not many situations in a real world situation where this happens though.

 

[MannyE]

Just found a Crown K2 on CL that's being sold along with two huge subs for peanuts. I think I like where this is going to end up! Specs on these things are ridiculous.

 

[lico]

The amp I picked up was a PSA-2 the pro version of the SA-2 Distinction Series amp (actually the SA-2 was the home version of the pro amp). I did a couple posts on it showing the filthy radiator fins on the power pack transistor modules and a clean up of whatever that stuff was on the faceplate and all the dust and other debris the fan threw into the unit while it was used without an air filter.



I don't see how Crown redacting nominal diagrams from their manuals proves your point about Crown. You say that they don't have specs in the league of the audiophile amps and this just indicates you may have too much emphasis on specs as my best sounding amplifier has the highest THD of any amp I own, a number that is distinctly not audiophile. But those amps sound great.

I am not saying higher distortion is necessarily audible, my point is the way pro amps are spec'ed allows for higher wattage to be quoted. That is all. You could take a Crown M1200 which is rated 300 at 8 ohms (1 kHz 0.1% THD) and it's probably about the same power as a M91 rated 200 continuous at 8 ohms,. which also claims to have dynamic power up to 300.

Anyway....somebody above admitted pro amps specs can be 10 to 20 pct higher proves my point. I never said you have to have 0.00001% or whatever THD to have a good sounding amp, you are assuming that. I have class D amps with higher distortion numbers that sound great too. Once again... my only point is pro amps juice the specs upward to give the impression they are more powerful amplifiers, which may not always be the case.

 

[Blue Shadow]

I am not saying higher distortion is necessarily audible, my point is the way pro amps are spec'ed allows for higher wattage to be quoted.

Any Crown amp sold into the Home Hi-Fi market was spec'd the same as any other home amp, using the FTC regulations. The pro only amps sure there are differences in the specs and there should be they are used in a different way.

 

[whoaru99]

Anyway....somebody above admitted pro amps specs can be 10 to 20 pct higher proves my point. I never said you have to have 0.00001% or whatever THD to have a good sounding amp, you are assuming that. I have class D amps with higher distortion numbers that sound great too. Once again... my only point is pro amps juice the specs upward to give the impression they are more powerful amplifiers, which may not always be the case.

Actually, you didn't really understand that point at all. There are many ways amps can be rated. Pick a point on the curve, but regardless it's the same amp. The rating represents what the amp does at that operating point, not "juiced".

 

[Samokan]

and it's probably about the same power as a M91 rated 200 continuous at 8 ohms,. which also claims to have dynamic power up to 300.

Do you have a specific crown amp in mind that qualifies your claim and have you made viable measurements to prove your point? According to your words quoted above you are not too sure of your argument, in using the word “probably”

 

[whoaru99]

Any Crown amp sold into the Home Hi-Fi market was spec'd the same as any other home amp, using the FTC regulations. The pro only amps sure there are differences in the specs and there should be they are used in a different way.

The way the spec is listed doesn't change the performance of the amp. It only represents a singular operating point. For pro amps, that's generally the point of maximum usable output, not some sandbagged number to show a pretty, but largely immaterial, distortion spec.

 

[PPstereo]

I run my entire system off a 16amp service, never tripped the breaker, would be very unlikely I would...

When I do a thermal test on these amplifiers, its not a single sine wave, its a composite waveform which if you listen to it, sounds like a machine gun with a growling and low multiple wave type noise going, its horrific and loads the amplifier nicely, running this into the amp on a 2.7Ω load both channels, it will reach thermal limit in 5-7mins, you can see the waveform truncated at the output, this is the condition it will draw 13.4 amps.
There are not many situations in a real world situation where this happens though.

Hey kevzep may I ask your opinion of the 5002vz design? Given your intimate knowledge of it... This is the only crown MA amp from back in the day that had different rail voltage correct? I have nothing against class H like amps. Heard great sounding ones from QSC , A&B and the home audio ones too.

Would you guess Crown took this approach with the 5002 to keep the power transformer a more reasonable size for the sake of practicality? Not really a bean counter reason but more a functionality reasoning? Also maybe some power draw benefits with this also. Keep it more friendly for USA 120v use too?

I remembered reading years ago how the VZ designation had something to do with an efficiency benefit. Coundnt recall what. Did the original 5000 also have multi rails?

Thanks for some insight if you dont mind. Great read here.

 

[drumbum]

Hey kevzep may I ask your opinion of the 5002vz design? Given your intimate knowledge of it... This is the only crown MA amp from back in the day that had different rail voltage correct? I have nothing against class H like amps. Heard great sounding ones from QSC , A&B and the home audio ones too.

Would you guess Crown took this approach with the 5002 to keep the power transformer a more reasonable size for the sake of practicality? Not really a bean counter reason but more a functionality reasoning? Also maybe some power draw benefits with this also. Keep it more friendly for USA 120v use too?

I remembered reading years ago how the VZ designation had something to do with an efficiency benefit. Coundnt recall what. Did the original 5000 also have multi rails?

Thanks for some insight if you dont mind. Great read here.

I believe the different rail voltages in G and H classes are about efficiency. Power consumption and heat.

 

[PPstereo]

I believe the different rail voltages in G and H classes are about efficiency. Power consumption and heat.

Yes agreed.

But it's also an approach that is sometimes used to keep manufacturing costs lower also. Not that there's anything wrong with that.

I'm simply wondering if given the capable power output of the 5002vz it had more to do with keeping size and weight lower.

I could be completely wrong about this. Just curious what kevzep says he thinks about it, or anyone for that matter.

On the very idea of cost and weight, love or hate them lol, look at stuff like carver m1.0t . For it's power output it's quite light weight and cost effective for its time especially. I just rebuilt 2 I ended up with simply to get the included jbl 240ti speakers. Fellow had them in mono driving each speaker.

My poor understanding of that 1.0t amp has me thinking the "power transformer" (I know it's far from a traditional one) internally creates the switching then possibly sends that off to a stepping winding within also to generate the various rail voltages. Again. I could be completely wrong in this idea. Neat amp no less. Loved the ps cap kit I bought to rebuild it.

All the best

 

[drumbum]

Yes agreed.

But it's also an approach that is sometimes used to keep manufacturing costs lower also. Not that there's anything wrong with that.

I'm simply wondering if given the capable power output of the 5002vz it had more to do with keeping size and weight lower.

I could be completely wrong about this. Just curious what kevzep says he thinks about it, or anyone for that matter.
Not be contradictory, but multiple rail switching adds complexity, hence more expensive to build.

I have no experience with a 5002vz.
On the very idea of cost and weight, love or hate them lol, look at stuff like carver m1.0t . For it's power output it's quite light weight and cost effective for its time especially. I just rebuilt 2 I ended up with simply to get the included jbl 240ti speakers. Fellow had them in mono driving each speaker.

My poor understanding of that 1.0t amp has me thinking the "power transformer" (I know it's far from a traditional one) internally creates the switching then possibly sends that off to a stepping winding within also to generate the various rail voltages. Again. I could be completely wrong in this idea. Neat amp no less. Loved the ps cap kit I bought to rebuild it.

All the best

 

[drumbum]

Yes agreed.

But it's also an approach that is sometimes used to keep manufacturing costs lower also. Not that there's anything wrong with that.

I'm simply wondering if given the capable power output of the 5002vz it had more to do with keeping size and weight lower.

I could be completely wrong about this. Just curious what kevzep says he thinks about it, or anyone for that matter.

On the very idea of cost and weight, love or hate them lol, look at stuff like carver m1.0t . For it's power output it's quite light weight and cost effective for its time especially. I just rebuilt 2 I ended up with simply to get the included jbl 240ti speakers. Fellow had them in mono driving each speaker.

My poor understanding of that 1.0t amp has me thinking the "power transformer" (I know it's far from a traditional one) internally creates the switching then possibly sends that off to a stepping winding within also to generate the various rail voltages. Again. I could be completely wrong in this idea. Neat amp no less. Loved the ps cap kit I bought to rebuild it.

All the best

Damn, let me try that again.

Not to be contradictory, but multiple rail switching adds complexity, hence more expensive to build.

I have no experience with a 5002vz.

 

[N8Nagel]

This discussion is suddenly relevant to my interests, as a Luxman TP-117 has just dropped into my lap.

Am thinking maybe one/a pair of Crown amps might be more suitable than using my HK775s or finding an old Luxman power amp.

Unfortunately I know next to nothing about pro sound. Could you recommend ideas to keep an eye out for that wouldn't break the bank but would be a step up from a pair of HK775s?

 

[Samokan]

Currently I have crown xls 2000 I’m using for my jbl l112. QSC plx2402 for my full range and crown xti4000 for my 15” woofers for lows. All purchased at reasonable price and sounds very good to my ears.

 

[PPstereo]

Damn, let me try that again.

Not to be contradictory, but multiple rail switching adds complexity, hence more expensive to build.

I have no experience with a 5002vz.

I can see that could be true in certain cases. However my crude understanding is that "certain" rail switching designs were often used as a means of keeping cost down. Carver and NAD would be good examples of this. Again these are generalities.

The size and weight of a power transformer that had to be wound to one rather high rail voltage would be large, costly and heavy. Hence why the afore mentioned brands did things their own unique way. But this also imposed limits on their amps in terms of long term high powered demands. And why they are often not appropriate amps for certain scenarios. Totally not trying to slam Carver or NAD. Very cool and good sounding amps. I own a few.

Also it allows different PS caps of different voltages and capacities VS a set of high capacity / high voltage only caps. Again cost measure. Having just rebuilt my 2 Carver M1.0T amps with their new PS cap board installed I just saw this notion in action.

Again these are VERY generalized examples. And I am no EE so dont think Im trying to be high and mighty in this.

Lastly a simplistic example of complexity vs cost. Look at a modern class D say 150 watt amp. You know those 8 lb wonders. Which do you think would be more expensive to build. A 150w class D 8 lb amp or a linear and or rail switching amp like were talking about. And OMG is the circuitry in one of those class D amps WAY more complex vs an old school approach to amp building.

Just trying to point out complexity and cost are not always directly equatable.

All good man. Who knows....

 

[Samokan]

Just trying to point out complexity and cost are not always directly equatable.

All good man. Who knows....

You’ve raised a good question PPstereo and I too am interested on an answer. Speaking of the class D amps they are amazing of what they can do in terms of functionality in having built in DSP functions. And yes light in weight but not in power.

 

[FONSguy]

Well, I really love my PSA-2. It has been rebuilt and recapped by a local Crown tech who does overflow work for Crown. Last year I had the power supply rebuilt with 4 identical (really!) caps, which, after Corey tweaked the amp sounds wonderful. I use a no frills DB System preamp and 4 KEF 104aB's recapped last year. I listen to lots of vinyl from a Grace F9e cart on an SME 3009 II Improved arm with fluid damper. My back-up amp when listening to just ONE PAIR of KEF's is a DB Systems DB-6 (40 watts /channel). I do not crank the system but the Crown is there for the headroom, especially when playing M&K pipe organ LP's. The amp is transparent, always clear and with lots of depth. So if you want it to sound good and play loud Get a Crown. I wanted to explain what else was in my system so to give you an idea of everything in the audio path. BTW - I usually keep my PSA-2 on all the time.

 

[Blue Shadow]

Well, I really love my PSA-2...I use a no frills DB System preamp

No wonder it sounds good those DB Systems preamps are very nice. One memorable system I hear was a single Quad ESL 57 driven by DB Systems. Depth and imaging, very memorable. Too bad the other Quad was out for repair.

 

[kevzep]

Hey kevzep may I ask your opinion of the 5002vz design? Given your intimate knowledge of it... This is the only crown MA amp from back in the day that had different rail voltage correct? I have nothing against class H like amps. Heard great sounding ones from QSC , A&B and the home audio ones too.

Would you guess Crown took this approach with the 5002 to keep the power transformer a more reasonable size for the sake of practicality? Not really a bean counter reason but more a functionality reasoning? Also maybe some power draw benefits with this also. Keep it more friendly for USA 120v use too?

I remembered reading years ago how the VZ designation had something to do with an efficiency benefit. Coundnt recall what. Did the original 5000 also have multi rails?

Thanks for some insight if you dont mind. Great read here.

The 5000/5002VZ essentially has one rail VCC+ and VCC-, its not a class H design like the Carvers and some Crests are with three separate rails.
The 3600VZ is also a variable impedance rail as well.

They do not switch from one rail to another like a class H does.

Basically there are two secondary windings for two DC supplies, these supplies are fully floating, there are two bridge rectifiers, two main caps, the normal state is that these two supplies run in parallel, when the demand is required, the VZ circuit will switch the parallel supplies to series for increased voltage, its done by three IRF540 FETS, there is a complicated VZ control circuit with current sensing etc to monitor the amplifiers performance.

I have attached the VZ circuit theory from the service manual, it is actually quite involved..

Yes efficiency and performance was a big part of the reason they came up with this design, it is patented by Crown, they are the only manufacture to use this topology.