Review and Measurements of Meier Corda Jazz Amp

[agjell]

No surprise here ...
The unit is marked as "Designed by ... Germany" not "Built by ... in Germany" so you guess where it was built ...

Yes, but this amp is required by law to be CE-compliant, or else the company wouldn't be allowed to sell the product from the EU. You can order the amp directly from the manufacturer through their archaic web site, and their company is registered in Germany. This makes me think that they actually meant to put the real CE-mark on there, but simply failed to do so. It's a story about complete lack of detail, everywhere in the product chain

 

[graz_lag]

... It's a story about complete lack of detail, everywhere in the product chain

Indeed, it's exactly like that.

 

[Nango]

Amir noted already in the first sentence where he claims about capitalization of the one word ..... This was going to end in a Desaster.....

 

[Dro]

No 50 mV test for IEM compatibility?

 

[graz_lag]

Corda translates String from English, or alternatively, Rope ...
You guess what the Corda owners would like to roll around Mr. Jan Meier neck after reading this review ...

 

[elira]

I would love to see a response from Jan Meier in this thread. But some of the comments are a little aggressive and that will most likely discourage him from doing so.

 

[Jimster480]

I would love to see a response from Jan Meier in this thread. But some of the comments are a little aggressive and that will most likely discourage him from doing so.

I think that people discussing the poor design and clear flaws is not "aggressive" by any means.

This just seems to be another example of a product that costs way too much with a gigantic profit margin for the seller and under-performing for the buyer.

 

[graz_lag]

I would love to see a response from Jan Meier in this thread. But some of the comments are a little aggressive and that will most likely discourage him from doing so.

Ultimately, he is the designer so he should defend his technical choices, no matter whether some comments may appear as "a little aggressive" ...

 

[Nango]

You won't find in a german forum not a single one thread where someone expresses the smallest doubt about his amps, this is what really makes me think, something is wrong in that business, and I can't remember having read in a magazine not a single criticism after tested and measured (what ever they did!!) His gear, always fine, always close to perfect german quality.

 

[elira]

You won't find in a german forum not a single one thread where someone expresses the smallest doubt about his amps, this is what really makes me think, something is wrong in that business, and I can't remember having read in a magazine not a single criticism after tested and measured (what ever they did!!) His gear, always fine, always close to perfect german quality.

I think it’s just not popular enough. You won’t find measurements for most amps because nobody cares. It’s a small company I don’t think there’s a conspiracy behind the lack of negative reviews.

 

[graz_lag]

His guitar 6th "corda" (string) was not in tune, and so the other five either, when he designed this amp ...

 

[Nango]

But so many positive reviews on the other hand? That's what I don't understand. I don't see conspiracy behind that but I certainly see a huge hype on his stuff, with no evidence for quality, until today, when I realized just the opposite.

And how is it never ever someone noticed or reported the distortion at 12 o"click the pot? It doesn't make sense. Some thing is weird here.

 

[DuxServit]

I would love to see a response from Jan Meier in this thread. But some of the comments are a little aggressive and that will most likely discourage him from doing so.

Oh come on, he’s a big boy

We’ve had John Siau from Benchmark. Also had other designers come defend their babies. Part of the normal evolution of good products.

 

[MRC01]

I suspect that connecting these amps to the AP as unbalanced shorted and fried their ground drive channels. That would explain the low power output, the high distortion, and the poor sound that Amir subjectively observed. The smoking gun is the fact that they measured the same whether balanced or unbalanced, which says the ground channel had no signal.
But that is just conjecture on my part.

 

[amirm]

No 50 mV test for IEM compatibility?

It is in there. I just post the comparison graph instead of showing it stand alone.

 

[amirm]

I suspect that connecting these amps to the AP as unbalanced shorted and fried their ground drive channels. That would explain the low power output, the high distortion, and the poor sound that Amir subjectively observed. The smoking gun is the fact that they measured the same whether balanced or unbalanced, which says the ground channel had no signal.
But that is just conjecture on my part.

Hey, don't scare me this way. No customer unit has been damaged under my watch....

I tested the AP analyzer and the common pin is definitely floating relative to the ground.

I hooked up my Tektronix Scope and using only the center/signal pin of each scope channel, measured the signal and common pins out of one headphone amp channel:

Seems like the out of phase signal (yellow) is riding on the "ground"/center pin.

Is this what you expect from a working unit?

 

[MRC01]

If ground is carrying a signal, that looks right.
If Meier's web page is correct, the ground signal carries 1/4 of L + 1/4 of R, inverted.
Left carries Left + Ground, Right carries Right + Ground.

So here's the mystery: if the ground is carrying this inverted signal, when you measured it as unbalanced, and then as balanced, you should have gotten two different measurements.

 

[Dro]

Assuming both left and right channel play the same signal, this would be expected.

 

[amirm]

So here's the mystery: if the ground is carrying this inverted signal, when you measured it as unbalanced, and then as balanced, you should have gotten two different measurements.

I used a random XLR to RCA adapter for the balanced measurement. So don't put too much value on them being right in that regard. I ran them to show that with that input fully floating it still didn't matter.

 

[NTomokawa]

So much for "German engineering".

Looking at where Benz/BMW/Audi/VW are going, I can't say I'm surprised...