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Are Audio Manufacturers Liable for False Claims, Bloated Spec's?


jjptkd

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6 minutes ago, Travis In Austin said:

Langston @Langston did that testing on same brand and type of analyzer. I will try to find link where he talks about some problems with Amir's testing, nothing major, but interesting the same.. 

 

It's off-topic to the issue of whether the Carver amp puts out the power they claim. But I thought it was interesting, in another context, that even with testing you need to really know what doing certain things on the analyzer do to the results. Even I could understand this and was a little surprised about this:

 

 

Here is what Langston @Langstonwas saying:

 

Interesting. Striking similarities between my scope measurements of the miniDSP amp. The ASR guy has a $35k APx-555 with a 1MHz bandwidth. My APx-515 has a 96kHz bandwidth and measurement of devices with significant ultrasonic output can cause slew induced distortion in the analog input stages. This is a fact for the analog input of ANY analyzer that is exposed to high level signals or noise above its passband. Thus I use an external low-pass filter designed for these kinds of measurements when using the APx-515.

 

No need to bother with this external filter with my 200MHz scope, which is what I used to start this thread. ASR didn't need the external filter because his analyzer can handle the 450kHz slew, BUT he did engage a 40kHz AES-17 filter (internal option for all AP analyzers*) to suppress the ultrasonic garbage in his results as shown here. This is an 8th order filter, thus the ASR measurement of the ultrasonic noise is wildly understated. The use of the AES-17 filter for digital audio type measurement is like grading on a curve - it gives the garbage producers better results with the excuse that "nobody can hear that stuff anyway". Of course we can't hear it directly, but we do hear the flat/hard results that are likely the result of it through aliasing and/or other mechanisms.

 

 

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11 minutes ago, the real Duke Spinner said:

Carver was always a Liar

Come on, really?   Really?  Have you heard and bench tested EVERY SINGLE one of his designs. I know you haven't, I'll answer for you.  Don't make a blanket statement like that without doing so n. Be fair. Come on guy... 

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1 minute ago, Westcoastdrums said:

Come on, really?   Really?  Have you heard and bench tested EVERY SINGLE one of his designs. I know you haven't, I'll answer for you.  Don't make a blanket statement like that without doing so n. Be fair. Come on guy... 

I have had a lot ..a lot of Bob Carvers stuff back in the 1990 era

It just did not perform to what the Specifications would lead you to believe Not that I did not like it, but with challenging Loads ..the amps would fall flat

Think ElectroStatic spkrs

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1 minute ago, Westcoastdrums said:

Come on, really?   Really?  Have you heard and bench tested EVERY SINGLE one of his designs. I know you haven't, I'll answer for you.  Don't make a blanket statement like that without doing so n. Be fair. Come on guy... 

Well Bob doesn't even own his name any more. So technically he isn't lying about this particular amp. 

 

He had a very rough patch in the early 2000s, he filed two patent infringement lawsuits on speakers/subs, and he lost both of them, one to Velodyne, and the other a Canadian Company that was bought by Klipsch several years later. 

 

Sunfire was doing well. Then he started, Bob Carver, LLC, and he was kicked out of that two years later, that went into Chapter 11 and they asked him back to save it, I don't think he did. 

 

What happened to Sunfire? Did Phase Linear test accurately? Or was he the whole reason for the FTC amplifier rule in 1974 to begin with LOL.?

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1 minute ago, the real Duke Spinner said:

I have had a lot ..a lot of Bob Carvers stuff back in the 1990 era

It just did not perform to what the Specifications would lead you to believe Not that I did not like it, but with challenging Loads ..the amps would fall flat

Think ElectroStatic spkrs

Electrostatic speakers kill MANY amps.  Folks buy amps around the speakers that need to play them with volume and tolerate 1.5 ohm dips. That's like saying I'm going to take my focus ST, put 5k into it and I'll race Ferraris.  The lesson remains the same, stay in your lane and know what you are trying to accomplish. 

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2 minutes ago, Travis In Austin said:

Well Bob doesn't even own his name any more. So technically he isn't lying about this particular amp. 

 

He had a very rough patch in the early 2000s, he filed two patent infringement lawsuits on speakers/subs, and he lost both of them, one to Velodyne, and the other a Canadian Company that was bought by Klipsch several years later. 

 

Sunfire was doing well. Then he started, Bob Carver, LLC, and he was kicked out of that two years later, that went into Chapter 11 and they asked him back to save it, I don't think he did. 

 

What happened to Sunfire? Did Phase Linear test accurately? Or was he the whole reason for the FTC amplifier rule in 1974 to begin with LOL.?

Well OK, frankly, I don't know the history and haven't heard plenty of his designs im sure, but this likely ISN'T the thread for what his amps are or aren't.  Have you tested his amps to the limit of your 82 dB sensitive speakers?  That's where shit will come into play.  Not for us horn guys, not for us., 

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From the Bob Carver Forum:

 

QUESTION: Bob,  A guy is claiming a 275 makes 17 watts with strange distortion numbers any thoughts?

 

ANSWER: Thats ridiculous, a 75 watt amp.. Isn’t it obvious? It is being test wrong or its damaged.. My amps can be difficult to test, difficult to get the grounding correct. I’ve been dealing with people testing my designs wrong and getting grounding errors effecting measurements, most of my life.

 

QUESTION: Bob is it fair to say that you design amplifiers for reproducing music into dynamic loudspeaker loads, more so than focusing on reproducing sine waves into load resistors?

 

ANSWER: There is some truth to that. My amps can perform way above there power rating for a time, a time being several seconds.

 

That first answer (the bold is mine) just doesn't make sense. If that's the case, footnote your specification sheet and provide the matter in which you tested it so that it can be replicated, like every other honest company does.

 

I can't remember what they got out to the ASR review/testing. But it was more than 17 I believe????? The fuse failed when he tried to max it out, I think twice. He was all worried there were only 3 fuses in the box. I was a little surprised that a testing guru didn't have a supply of 3A fuses on hand. 

 

I guess there is one other possibility in all of this. The guy Frank Malitz bought the naming rights for Bob Carver, Bob supposedly designed the amp (which he acknowledges in the Q and A (example above), and they are being made in California by the guy who does Wyred 4 Sound, maybe they cheapened it without Bob's knowledge?

 

An 3 prong AEC plug socket that isn't even grounded on the inside? That was the most mind blowing to me. That's a major, major problem that could get whoever owns this company is to real hot water. 

 

As others have said, it appears that Bob had a chance to be paid something, maybe X per amp sold, no capital at risk, company owned by somebody else, looking to cash in on a name. 

 

I'm glad it sounded good to West Coast, and hope the same for FJD, it's going to put out the power with high sensitivity speakers, but I feel bad for those who may have gotten it with lower efficiency and didn't realize until too late. 

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33 minutes ago, Travis In Austin said:

Well Bob doesn't even own his name any more. So technically he isn't lying about this particular amp. 

 

He had a very rough patch in the early 2000s, he filed two patent infringement lawsuits on speakers/subs, and he lost both of them, one to Velodyne, and the other a Canadian Company that was bought by Klipsch several years later. 

 

Sunfire was doing well. Then he started, Bob Carver, LLC, and he was kicked out of that two years later, that went into Chapter 11 and they asked him back to save it, I don't think he did. 

 

What happened to Sunfire? Did Phase Linear test accurately? Or was he the whole reason for the FTC amplifier rule in 1974 to begin with LOL.?

You know ...

I really do not know the Sunfire debacle

Sunfire just faded

 

I like my Phase Linear 400, but have never tested it ..it's pleasing, musical ..that's enough for me

My father had an electronic's  R& D Company, I had the Equipment, but never bothered to test ...My experience with my PL amps has been they fall flat when pushed to rated power

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28 minutes ago, Westcoastdrums said:

Have you heard it? If not, Travis you are PURELY speculating.  There's 3 of us I know that have owned it, @Shakeydeal, @jjptkd and I. Who else here has OWNED IT and tested it in their own system...? 

You are not getting what I'm saying. I don't dispute that it sounds good, or better than any other amp somebody has heard before. 

 

But the Bob Carver Corporation (which is defunct in Washington State) isn't Bob Carver, it's a guy from the sales side of audio, and they guy who builds stuff in California, using a Bob Carver design, and they have put out specs that it is a 75+ watt amp. 

 

My serious question is, according to ASR, how did it measure up? It looks like it hit the specs I see, but I don't know enough about this testing stuff to say, well it looks like the guys who said this was a 15W amp are all wet. 

 

Like you said, and I also said, for that money, you can't find a better sounding amp for less, and it drives my speakers perfectly, then they are golden. 

 

But if for that price you could have gotten as good, and at spec, and you are blowing fuses constantly, here's your chance.

 

But going back and looking at the numbers, from those specs that ASR did, it looks like it got close (60W) in one type of test, and above 74W in short bursts.

 

So it looks like they got the power spec so there is no room to complain there. Is that correct?

 

People can yak all they want about the distortion, like you say, who cares what the distortion rating was if it sounds good in your system. 

 

So my next question would be, if it's hitting 60W at the rated 70 ohm spec, and can peak above 70, does that mean it does not have the 15w Edcor transformers in it like originally suspected?

 

They are continuing to say in ASR that it's fraud, etc., but I'm not sure anymore, because I don't know enough what these numbers mean as compared to what the FTC requires on power specs. 

 

 

 

 

 

 

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1 minute ago, Travis In Austin said:

You are not getting what I'm saying. I don't dispute that it sounds good, or better than any other amp somebody has heard before. 

 

But the Bob Carver Corporation (which is defunct in Washington State) isn't Bob Carver, it's a guy from the sales side of audio, and they guy who builds stuff in California, using a Bob Carver design, and they have put out specs that it is a 75+ watt amp. 

 

My serious question is, according to ASR, how did it measure up? It looks like it hit the specs I see, but I don't know enough about this testing stuff to say, well it looks like the guys who said this was a 15W amp are all wet. 

 

Like you said, and I also said, for that money, you can't find a better sounding amp for less, and it drives my speakers perfectly, then they are golden. 

 

But if for that price you could have gotten as good, and at spec, and you are blowing fuses constantly, here's your chance.

 

But going back and looking at the numbers, from those specs that ASR did, it looks like it got close (60W) in one type of test, and above 74W in short bursts.

 

So it looks like they got the power spec so there is no room to complain there. Is that correct?

 

People can yak all they want about the distortion, like you say, who cares what the distortion rating was if it sounds good in your system. 

 

So my next question would be, if it's hitting 60W at the rated 70 ohm spec, and can peak above 70, does that mean it does not have the 15w Edcor transformers in it like originally suspected?

 

They are continuing to say in ASR that it's fraud, etc., but I'm not sure anymore, because I don't know enough what these numbers mean as compared to what the FTC requires on power specs. 

 

 

 

 

 

 

Yes, I hear you and I have read considerably through the ASR threads.  I don't own this amp any longer and didn't but it new (my amp arrived damaged and not even close to rating..)   knowing what I see now, I would NOT buy one new.   There is a filly revamped dynanco here in the garage sale if I was so inclined.... 

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50 minutes ago, the real Duke Spinner said:

You know ...

I really do not know the Sunfire debacle

Sunfire just faded

 

I like my Phase Linear 400, but have never tested it ..it's pleasing, musical ..that's enough for me

My father had an electronic's  R& D Company, I had the Equipment, but never bothered to test ...My experience with my PL amps has been they fall flat when pushed to rated power

I had PL amps, I could never get them anywhere near the top. 

 

I was curious, so I looked it up, Sunfire in 2011 was doing about 15 million a year, Bob and his wife owned 100 percent of the company, they sold it a conglomerate I'm guessing for a pretty could chunk of change. My guess is that he is in a retirement/hobby mode now, the right people approached him about selling his designs, but he had none of the headaches. The Frank guy who bought the rights, worked at either Carver or Sunfire with Bob so there was that, and Frank got the guy in California to build them.

 

Personally, I would take the 700W Coffee can amp. 

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3 minutes ago, the real Duke Spinner said:

Who cares about specifications anyways. ..??

It's not what I listen to. 🙂

 

Half the time I am using an anemic Crown D45 for an amp

It's not really the point. It started out with who is responsible for specs. And then it was, this guy tested one and it less than a 1/4 of spec, and has 15W Edcors in it. Now, it is look more like 60W, and 75 watt peaks before blowing a fuse. 

 

It would matter if you bought the amp new and were running typical lower efficiency speakers on it expecting you were getting what you were used to from your Mac 275, which does put out a real 75 watts at .1 percent THD. 

 

So I'm gathering it's a much closer question now. But, there are going to be some that see the 60W vs 75W (if I'm even saying that right, or the testing that ASR is correct) and will say "it's close enough for me", and some, "yeah it sounds good, but I could have got a good sounding amp for same, or less that is a real deal 75W, or a 60W amp for less." I don't know.

 

But it doesn't look like I bought and paid for a 75w amp and got a 15W amp anymore. 

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On 12/30/2021 at 1:55 PM, jjptkd said:

As I've said before I love this amplifier it does everything I need it to do for me whatever power it actually delivers is enough for my speakers in my space and it's a solid performer in bass clarity and has a nice 3D depth of sound to it, honestly I have no complaints about this amplifier but still if these numbers come back well below spec like everyone seems to think they will I can't help but feel cheated a little, am I wrong in feeling this way?

I'm glad it didn't come out way below the way some people were speculating 17 vs. 75.  I didn't realize at first it was a kit amp they were testing, I thought a member of ASR also tested a production amp. From Langston's testing of a Hypex vs. ASR's tests, I still dont know if they are testing distortion the way it is supposed to be with that Analyzer, so I wouldn't worry about that. 

 

The power ratings I saw were it was pulling 60W (easily) and could do 75W peaks. Does it blow fuses for you at all?

 

If it still sounds good and you like it, I'm glad it worked out. 

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Great discussions!

 

To return to the OP original questions (and to add a little humor) "Are Audio Manufacturers Liable for False Claims, Bloated Spec's?"  Well, apparently not otherwise "quality" companies like these would be in trouble...

image.thumb.png.be2d654c408ead59be675e16e0f2013d.png

 

I have always been from the school of thought where I let my ears judge weather I like something and then I let my wallet decide if I can afford that something!  However, I don't like it when companies are misleading in order to get a sale.  If I feel cheated, I just simply won't support that company again. I vote with my $$$.  It usually boils down to the marketing department trying to tell us why their widget is better than someone else's widget.  I would love an honest spec sheet so I can start my searches there and ultimately let my ears do the deciding before a final purchase.  For example, if I'm looking for a random 8 channel amp that's at least and honest 100 watts RMS at less than .1%thd from 20h-20khz, then I'm probably going to stay away from brands like this claiming 1000 watts per channel max and then in the next line state that it's 100 watts per channel RMS. Sure , it may have made 1000watts for a nano-second right before it started the lab on fire sending employees scrambling for fire extinguishers!

 

image.thumb.png.26d1fb7f7a2ceb183c07d4e996263106.png

 

I hope this at least provided you with a little comic relief!  

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10 hours ago, Travis In Austin said:

I'm glad it didn't come out way below the way some people were speculating 17 vs. 75.  I didn't realize at first it was a kit amp they were testing, I thought a member of ASR also tested a production amp. From Langston's testing of a Hypex vs. ASR's tests, I still dont know if they are testing distortion the way it is supposed to be with that Analyzer, so I wouldn't worry about that. 

 

The power ratings I saw were it was pulling 60W (easily) and could do 75W peaks. Does it blow fuses for you at all?

 

If it still sounds good and you like it, I'm glad it worked out. 

 

I can clear a few of your questions up.

 

As for Amir worried about fuses his house was basically under water at the moment which is why it took him so long to do the review, it's not like he doesn't have 3A fuses more that he didn't want to go looking for them as stuff may be boxed up and all over the place. I myself keep spare fuses but 3A is the most common and I have run out of them often.

 

All of the amps tested could make 75 watts of power, but only at 1kHz and with higher than 1% THD. The major problem with this amp is the fact they used an output transformer rated for 15 watts. That doesn't mean the transformer can't pass higher amplitudes at certain frequencies, like the standard 1kHz used for testing, what it does mean is that for the audio band it is rated for 15 watts, low frequency performance is directly related to the size of the transformer. That's the problem with the Crimson 275, it isn't anywhere near the specified bandwidth to power and distortion.

 

An honest company goes by industry standard specifications. which is your rated output power should be for full bandwidth stated, at maximum distortion stated, and for RMS power into rated load for extended periods of time. So for 75 watts into 8 ohms you should be able to see on a scope a 34.3 volt peak waveform (sine wave) for all interested frequencies and this should not blow fuses. I can purposely clip amplifiers and not even blow fuses for honest amplifiers. You should be able to run a decent amplifier at rated maximum output for long periods. After I do major repairs I run the amplifier at it's full rated output into a dummy load for extended periods of time (hours) to make sure all is well. The Crimson 275 shouldn't be blowing fuses anywhere under 34.3v peak signals, it shouldn't even blow them when clipping either.

 

Amir's testing is completely adequate to deduce this amplifier is a complete fraud. It's limited by the output transformer to being a high quality 15 watt amplifier regardless if it can produce 70 watts at 1kHz, that's not how you rate an amplifiers output power. This is where the confusion sets in, people not in the know see the amp can produce the power for short periods before blowing fuses but that is not how it should function, it should pass that waveform constantly into load at all interested frequencies (20Hz-20kHz).

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