Too good to be true? Chinese CVR D-Series Amplifier Measurement Request

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Billy Jukes

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Joined 2017
#1
Hello Everyone

This discussion is in reference to the Chinese CVR D-Series Amplifiers.

LINK: GUANGZHOU CVR PRO-AUDIO CO.,LTD--Professional speaker, Kara OK speaker

The stated output power of these amplifiers is unreal. Even if the output is half that of the stated output, these would still be excellent value for money.

There are lots of these Chinese amplifiers floating about thanks to Alibaba and I'm aware loads have been discussed on this forum already. What makes these ones different are;
1. They're 1U
2. They're not trying to copy another manufacturer aesthetically

This makes them more appealing to own opinion.

Considering this, has anyone had any experience with these amplifiers?

If so, I'm sure we would all benefit for your experience and if anyone has any measurements, these would be very useful!

I'm starting this post knowing the potential lack of reliability of some products manufactured in china, therefore please do not comment about the reliability and performance if you have not had any experience with these amplifiers.
 
#2
2X3000 watts into 8 ohms is possible from 220V mains, but you'd need a 30 amp circuit. In real use, 20 amps could do. You won't get that kind of power from 120V mains, but you wouldn't expect to. In North America you'd have to run the amps at 208V for full power, and that's not unusual on shows.

As to how well the amps can get rid of the heat and not shut down, well - that would be just a guess. 🙂
 
#3
To me it looks like a copy of Powersoft Digam series, which are quite eligible for that as the technology is old, the parts used are old stock and somewhat outdated, and mainboard is or was all thru-hole parts. Also the power specs are only met temporarily, and there is overshoot in the limiting, there is a video on youtube showing these amplifiers (K20 I think) cut down to almost no signal (and highly clipped) after a few second bursts at full power.
 
#4
Apparent internals pic posted at speakerplans Amp Forum.

TO GOOD TO BE TRUE?? Chinese CVR D-Series Amplifie - Speakerplans.com Forums - Page 1



21151720_10213565092536962_7818699567387146601_n.jpg
 
#6
Some of us run power hungry subs 🙂 The output is most likely rated in milliseconds or fractions of - real world power most likely much less than claimed. 6kW might be 200 wpc continuous. Hence, the OP request for measurement.
 
#7
Wow!! Cost-reduced Powersoft clones hahaha

The Italians like illusive fat-sexy-looking stuff, like the X series (ironically: it is said to only produce 1/10th rated power continuously, in speakerplans forums). But what happens when it can be done better with less? Like the Chinese clones being at some fields an improvement over K series and competing favorably with latest X series. Furthermore, the Chinese clones have an interesting-looking front panel look too, it reminds to ornaments evoking wheat as in Ancient Rome.
 
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#8
As in the case of the powersofts, there is no way it can do close to rated power for long time with such small power supply components.

Of course, this stuff using FETs rated 300V, 400V, 500V and 600V, and bypassing body diodes with faster diodes, is going to become outdated when SiC FETs become affordable, but these SiC FETs are in direct competition with existing silicon technology, often from same component manufacturers, so it is going to take some time.
 
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#10
Diogenes said:
I've no trouble clipping the 2600W amp powering my sub when I get a little carried away and not at ear-bleeding concert levels either. 3kW wouldn't be noticeably different. Different tastes in music have different power demands.
Click to expand...

Somehow true...
...just go for inefficient speakers, designed for small cabinets, but allowing huge Xmax. ...Put them in small closed cabinet(s) and Linkwitz transform it to be linear down to 15Hz...
Listen to music which contains a lot of low frequencies and even subsonics - there you are. Sound impression with some kW will be a massive one and shake the walls, but at the same time won't ring in your ears with the perception of excessive loudness ( ...nevertheless stressing your ear drums with huge excursions...).
 
#15
ltdf said:
Apparent internals pic posted at speakerplans Amp Forum.

TO GOOD TO BE TRUE?? Chinese CVR D-Series Amplifie - Speakerplans.com Forums - Page 1



21151720_10213565092536962_7818699567387146601_n.jpg
Click to expand...

The power supply gets airflow from the right fan, the one channel in the mid gets airflow from the middle of the picture, the amp on the left does NOT get any direct airflow. At such power a hotspot is guaranteed, capacitors directly adjectant to the hot heatsink/hotspot, the channel failure is almost guaranteed on high power use (well, what for would you buy such an amp anyway?), you can literally wait for it to happen.

That's a major design fault, visible at the first glance. That only happens with very inexperienced developers.
 
#16
ChocoHolic said:
Somehow true...
...just go for inefficient speakers, designed for small cabinets, but allowing huge Xmax. ...Put them in small closed cabinet(s) and Linkwitz transform it to be linear down to 15Hz...
Listen to music which contains a lot of low frequencies and even subsonics - there you are. Sound impression with some kW will be a massive one and shake the walls, but at the same time won't ring in your ears with the perception of excessive loudness ( ...nevertheless stressing your ear drums with huge excursions...).
Click to expand...

I'm mostly in agreement, but my situation involves a 91dB driver, so average efficiency, in a 14ft³ enclosure with the only EQ being a couple of cuts to address room issues as room gain pulls the low end up at about the same rate as the sub rolls off. (I got lucky there.)

It doesn't take a lot of subsonics or the sort, just albums that haven't been mastered according to old vinyl era habits with a brickwall highpass at 35Hz and heavy compression. Drums, for instance, that haven't been compressed into mush call on the power like mad. A kick drum isn't all that low digging, but it'll get the red lights flashing fine with a good, clean rock recording and, of course, no clipping sounds better than clipping.

Pano said:
What music contains a lot of low frequencies and even subsonics?

BTW, this just a commercial PA amp. Shouldn't it be over in the live sound section?
And is there anything DIY about it?
Click to expand...

Classical and anything acoustic that's not been filtered, for instance. Rare as that is, unfortunately. Pianos and upright bass just don't sound right on a lot of recordings for that reason, they've lost the resonance of their body that makes them load a room so strongly. It's like listening to speakers without tweeters. Sure, the fundamentals don't exist in that range, but the sonic illusion is lost without the other sounds created by the instrument during play and the interplay of harmonics.

But, yes, electronic genres outside of manufactured pop pabulum. I've no clue about EDM, but it shows up elsewhere. I've attached a spectrum I took of an Industrial Ambient "song" I ran across. It's seven minutes of that. Though it seems a bit bland at first, it's become a favorite demonstration track of mine for the power of subsonics not for some insipid idea of rumble and rattle, but of what it does to the listener. On a system capable of reproducing it, I've yet to encounter someone who didn't quickly feel heart-poundingly anxious or outright nauseous for it in short order. It wakes up the reptilian brain with deep genetic memories of predators' calls from ancient times when we were the hunted, I suppose.

Well, PA amps offer cheap power for DIYers on a budget seeking more channels of amplification for active or demanding designs. Sure, I'd love old, big iron Krell-clone monoblocks powering everything in a fully active system and a separate sub-panel to give each their own breaker, but I have to be a tad more realistic. The one pro amp I use currently I use on my sub where the power counts the most and I can't afford an audiosnob approved amp, bought or DIYed, of sufficient oomph to do a comparable job. DIY is also about being resourceful, afterall. Knowing of good commercial options for situations or times where a DIYed amp isn't a reasonable use of resources is useful knowledge.
 

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