Danny at GR getting bad Talk Back from many of his viewers

[DSJR]

Second hand story but from a trusted source... Back in the 80's and 90's, a certain audio techie consultant 'guru' measured and reviewed a particular very high end US amplifier and found it wanting. So concerned were the designers they flew over and checked his test equipment and found it out of calibration. Never again or at least for many many years, was said high end maker reviewed in that magazine or by that reviewer (unlike its direct competitors which are very well known on these shores).

Whether the above is entirely true or not doesn't really matter here, but I'd politely suggest that ANY gear tester worth their salt and in addition to being meticulous in the accuracy of the physical/material side of the testing, keeps their test gear properly checked and calibrated, just for consistency so the results are repeatable and that they tally with other third party reviewers results.

I repeat, the Concert 8 *when new* was never short of high frequencies and I rather liked them actually...

P.S. Not ALL tweeters with ferro-fluid dry out and one UK maker went to huge lengths to prove it with the tweeters they use (SEAS based I believe). Maybe it's only certain climates which causes issues?

 

[Stingpung]

I have experienced the Concert 8 and 11 and can say they are fantastic speakers, it shouldn't be a surprise with Seas excel drivers that can be found in speakers in the 100.000$ class.
The Concert8/11 are considerd the best speakers jamo ever made. they really tried to enter the "high end" category in the late 90s to mid 2000s, but they failed and got back to make lots of money with best buy budget friendly speakers like they did before, with Great sucsess(they where at one point the largest speaker company in the world pumping out cheap Stuff) The only Jamo series that can trump the concert 8/11 are the Jamo R907/909, but they are waay up there in price. As far as Jamos, i wouldnt touch anything but the 8s 11s and R907/R909 But they really did a legendary job at the pricepoints. The Concert 8s beat the crap out of B&W competator at the time the 805N at Half the pricepoint, thats why they failed n got out of the "high end marked, they where to cheap, and they did some shortcuts to get there.(Great job Danny, bully the people trying to give us quality with some compromise to keep the price down) Whatever.. Anyone that bellive this is a crap speaker with crap components should buy one, you can get it for 500$ and sell for 500$ than you realize what a steal that is, best steal in audioworld if you ask me!!.. But hey, its a nice day

 

[DanielT]

Danny may be an experienced designer but his experience is from decades ago and he has not progressed to keep up with technology. He preaches about taking your sound to the “next level” but seems more like an excuse for not taking his own game to the next level. He continues to use old proprietary drivers with old measuring equipment and processes. As with other old school designs, this can sometimes yield a nice sounding speaker but rather than using science to get to the next level, Danny promotes his magic beans (custom cables, special caps, tube connectors, cable risers and cryo).

While I get the attraction to many of these mystical upgrades, they are much like the latest diet fad. They may look promising initially but most eventually leave people unsatisfied and looking for the next quick fix. When you start to look more objectively at what you eat and how much, the results are much more beneficial. Amir’s (and other more objective) reviews help us to better understand what we are consuming.

The bottom line is not to succumb to audiophile junk food!

I'm not getting much wiser to how Danny sees things. In the video, #56 Danny is careful to point out that there is nothing wrong with his measurements. But then ignore measurements and 13:40 into the video say:

I will not go in and change anything in the crossover. Again, they (Polk) did a great job. ... .But we can put there tube connectrors and make a better internal wiring.

According to Danny, it will lead to:

Much better quality. They will measure exactly the same but it will be better clarity, better resolution, better details. It will open up the soundstage. Better depth, better separation.

Or ok I get that he wants to sell his upgrade kits but still.

Danny does not measure distortion in and of itself, if it would make any audible difference with his tube connectors and better cable quality between the crossover and the drivers in the speaker box? I have an extremely hard time believing that. Besides, it could be something Danny could measure, but of course he doesn't. He probably knows what the result would be.
(zero audible difference)

 

[TimoJ]

 

[DanielT]

It made sense that Danny should test further and think about possible errors. I think that was well reasoned by Danny.

That Danny then comments about ferrofluid tweeters was interesting. He clearly reads this thread.

 

[Deleted member 48726]

A reasonable weighted response video from him. Even though I think he did it to keep the customer happy that sent him the speaker and to keep people from seeding doubt about his other kits.. He is good at navigating in these waters.

 

[RickS]

It made sense that Danny should test further and think about possible errors. I think that was well reasoned by Danny.

That Danny then comments about ferrofluid tweeters was interesting. He clearly reads this thread.

Sounds like backpedaling and spin to me…

Note Danny was not planning anything until the owner questioned his work. We are all human and make mistakes. However, if he suspected defective drivers, then the drivers should have been repaired or replaced. He also ignored published review and driver measurements that contradicted his. Instead we get his usual whining about how bad the vendor‘s choices were and how he is going to fix the poorly designed crossover. The tweeter measurements clearly showed much lower output than an experienced designer would expect, but he chose to ignore all the objective data and redesign the crossover anyway.

Also note the upgrade is still posted to the GR website while he reconsiders his “fix”. Until he pulls all his snake oil products and videos from the net, not sure why he should be given the benefit of the doubt that anything he is peddling is worth buying.

p.s. Upgrade kit was removed from website slightly after I made this post.

 

[amirm]

Whether the above is entirely true or not doesn't really matter here, but I'd politely suggest that ANY gear tester worth their salt and in addition to being meticulous in the accuracy of the physical/material side of the testing, keeps their test gear properly checked and calibrated, just for consistency so the results are repeatable and that they tally with other third party reviewers results.

I doubt that story is true (how would that vendor prove calibration was wrong???). But it certainly is not valid these days. There is not much that goes out of calibration in todays audio measurement tools. If it did, then your DAC would be subject to same! I asked Audio Precision directly about this and they said they only recommend calibration when you have contractual obligations, government contracts, etc. where you want to show some traceability.

When I sold my 20 year old Audio Precision analyzer a few years ago, it was still completely accurate. The new unit measured just the same.

 

[thecheapseats]

...When I sold my 20 year old Audio Precision analyzer a few years ago, it was still completely accurate. The new unit measured just the same...

same with the Fluke high-end 4 1/2, 5 1/2 and 6 1/2 digit dmms... I would send mine out for cal every two years or so - and talk to the the techs occasionally (when they would let that happen) - who would tell me I should save my money unless I found a diff between measurements...

 

[Doodski]

same with the Fluke high-end 4 1/2, 5 1/2 and 6 1/2 digit dmms... I would send mine out for cal every two years or so - and talk to the the techs occasionally (when they would let that happen) - who would tell me I should save my money unless I found a diff between measurements...

I bought a used and simple Fluke 8010A bench multimeter that had a calibration sticker and the instrumentation shop that I bought it from said the same thing. They stay in calibration most of the time. Calibration is important for legal reasons and such but other than buying gear with a cal certificate and sticker I never bothered getting a re-cal on any of my gear at my expense.

 

[thecheapseats]

I bought a used and simple Fluke 8010A bench multimeter that had a calibration sticker and the instrumentation shop that I bought it from said the same thing. They stay in calibration most of the time. Calibration is important for legal reasons and such but other than buying gear with a cal certificate and sticker I never bothered getting a re-cal on any of my gear at my expense.

yep -cal was damn important when aligning (and printing tones) on analog 2'' and 1/2 and 1/4 inch two-track machines back in the day - with a lot of downside career-ending liability if I got it wrong...

oddly, the engineer who did the original design of my first fluke dmm - the 8060A - was up on eevblog a few years back and was gracious enough to talk me thru my self-rebuild/refurb of that 8060a with a few dozen public as well as direct messages... he knew all the tricks...

 

[Deleted member 48726]

Sounds like backpedaling and spin to me…

Note Danny was not planning anything until the owner questioned his work. We are all human and make mistakes. However, if he suspected defective drivers, then the drivers should have been repaired or replaced. He also ignored published review and driver measurements that contradicted his. Instead we get his usual whining about how bad the vendor‘s choices were and how he is going to fix the poorly designed crossover. The tweeter measurements clearly showed much lower output than an experienced designer would expect, but he chose to ignore all the objective data and redesign the crossover anyway.

Also note the upgrade is still posted to the GR website while he reconsiders his “fix”. Until he pulls all his snake oil products and videos from the net, not sure why he should be given the benefit of the doubt that anything he is peddling is worth buying.

p.s. Upgrade kit was remove from website slightly after I made this post.

Of course it's spin. But I still think that behaviour like this follow up video should be encouraged regardless.

 

[JSmith]

He does imagine the audience numbers if he presented in just a pair of speedos.
Keith

Budgie smugglers... I'll just get that out of my minds eye thanks.


JSmith

 

[amirm]

BTW, reading his return policy, it seems little can be returned now. For example, a cable is considered a "custom" product and once received, you own it and can't even return it! Good thing I got one of those and tested it already. He says the same thing about his finished speakers. Even his kits may not be returnable as he says they have to be like new condition. As soon as you screw those parts into a cabinet, it won't be like new so again, you are stuck with them. This is some of the most restrictive terms I have seen for an online business. Without the ability to hear his bits in advance, people need better terms than this.

And of course all of his claims about buying his cables and if not liking them, return them, is now false:

"Custom Orders (Finished cables, cabinets, and speakers)​

(Applies to all orders placed on or after August 11)

All fully completed cables, finished cabinets, and speakers are all custom built to order.

• Full-refunds are only possible if cancelled within 24- hours. (standard 3% cancellation fee still applies)
• Partial Refund: Once assembly has begun on your order, only a partial refund is possible up, to the remaining cost of labor and materials at time of cancellation.
• No refunds OR cancellations at, or after, the time of completion/delivery."

 

[Mart68]

possibly had a lot of stuff coming back. Those terms would not be legal in EU or UK.

 

[JSmith]

Those terms would not be legal in EU or UK.

Nor here either.

Has Danny become the non-refundable snake oil king?


JSmith

 

[MAB]

Really hard to believe this is a properly working Seas tweeter. It rolls off an octave lower than a typical Seas tweeter. It does look like a TC25CF-001, as mentioned earlier.
Danny's measurement with a trace I made superimposed on top of the measurements from Seas.

We can debate how accurately I traced Danny's measurement. But it really looks like a degraded tweeter.

A brief description of the speaker from 1987 Stereo Review:

https://www.worldradiohistory.com/hd2/IDX-Audio/Archive-Stereo-Review-IDX/IDX/90s/Stereo-Review-1997-02-OCR-Page-0042.pdf

The tweeter is silver voice-coil, and is ferrofluid cooled according to Hirsch. Probably a variant of the Excel or Prestige soft-dome but missing the last octave and some sensitivity.

I ran the car stereo install bay at a very nice store for years. We worked on fantastic cars, and some real junkers. We always confirmed proper operation before service, de-install, or modification. New drivers too since we had plenty of coil-rubs and other electrical defects on new stock. We had an unfortunate but surprisingly effective policy of handing a set of defective Jensen Triaxials to any new installer, having them do the install and seeing how far they got (typically full install), then making them replace the speakers outside in the hot Central Valley sun. It isn't worth it to work on a custom Cadillac without knowing the exact state of the equipment. A measurement like this is just screaming that something is wrong with the tweeter, and it is mystifying why you wouldn't suspect the tweeter if you saw the measurement.

 

[beagleman]

Despite all the criticism of Danny, he is an experienced loudspeaker designer. I can't imagine him making any major mistakes with LS measurements.

But there are also permitted tolerances for calibrated measurement microphones and if the DUT is not identical, there are also deviations due to the model tolerances of the speaker manufacturers.
These tolerances can cause a good +-1-2dB or more deviation in the FR measurements.

In a round robin test of 13 DIY loudspeaker designers, the frequency response measurements with calibrated mics of an identical DUT were compared with the measurement in an anechoic chamber. Ignore the deviations below 300Hz, which are caused by the gated measurement:
View attachment 324430
In most cases the deviation is +-1dB, but it can also rise to +-2dB in places.

In my case, the deviation was around +-1dB compared to the measurement of the identical DUT in the anechoic chamber:
View attachment 324434

When comparing frequency response measurements, it must therefore always be borne in mind that deviations can occur due to:
- Tolerances of the calibrated measurement microphones
- Deviations due to the measurement method. Gated measurements lead to additional smoothing, but anechoic chambers also have tolerances, especially in the low frequency range.
- Manufacturer tolerances for loudspeakers of the same series. This could easily be +-1.5dB.
- Differences in the choice of reference point during measurement. Center tweeter, between tweeter and midrange driver,...
- Different environmental conditions during measurement - temperature, humidity, measurement distance,...

Taken together, +-1dB is already very good for gated measurements. With Klippel NFS and anechoic chamber I would expect +-0.5dB, depending on the smoothing of the FR - more than +-0.5dB deviation in the low frequency range.

Wharfedale Linton Upgrade Kit (Pair) | GR-Research

gr-research.com

Wharfedale Linton 85th Anniversary Speaker Review

Wharfedale Linton 85th Anniversary Review

www.erinsaudiocorner.com

This is the ONE of a few I found to not match up well at all. The Wharfedale Linton.

I put links only to the plots, too lazy to capture the images, but we are talking a good bit more than a slight variance here. Enough that Erin's looks close to perfect, and Danny's looks like it NEEDS fixed........a bit extreme.

 

[fpitas]

it is mystifying why you wouldn't suspect the tweeter if you saw the measurement.

In Danny's case I suspect it fed into a narrative. Replacing the tweeter would not serve his purposes.

 

[RickS]

Wharfedale Linton Upgrade Kit (Pair) | GR-Research

gr-research.com

Wharfedale Linton 85th Anniversary Speaker Review

Wharfedale Linton 85th Anniversary Review

www.erinsaudiocorner.com

This is the ONE of a few I found to not match up well at all. The Wharfedale Linton.

I put links only to the plots, too lazy to capture the images, but we are talking a good bit more than a slight variance here. Enough that Erin's looks close to perfect, and Danny's looks like it NEEDS fixed........a bit extreme.

Danny’s SPL range is only 25 dB vs (more typical) 50 dB from Erin’s measure…

The correct way to compare these is to get Erin’s Klippel data and then change its smoothing to 1/3 octave and scaling to 25 dB.