Greg Timbers Interview

[Champster]

I just found this interview on Erin's Audio Corner on YouTube.
https://www.youtube.com/watch?v=afeTHLLp-EI

[BMWCCA]

Thanks. I'm enjoying it.

Find it hard to believe the expert/host didn't know what an L250 is. You're supposed to do your homework prior to an interview: http://www.audioheritage.org/html/people/timbers.htm

http://www.audioheritage.org/html/people/timbers.htm

[Champster]

Thanks. I'm enjoying it.

Find it hard to believe the expert/host didn't know what an L250 is. You're supposed to do your homework prior to an interview: http://www.audioheritage.org/html/people/timbers.htm

http://www.audioheritage.org/html/people/timbers.htm
Agreed. Erin seemed unprepared for that interview.

[speakerdave]

Some highlights for me:

I love it, in the context of the old penchant for Bose-bashing in these forums, that GT seemed intrigued by the basic idea of the BOSE 901 and said that if the shortcomings had been addressed, it could have become quite an interesting speaker. That is: 1) use higher quality drivers; 2) provide some decent-sounding electronics in the EQ box; 3) change the front single driver into a two-way with a tweeter because there is no way to get any decent treble by EQ'ing a five-inch full range.

I liked hearing GT confirm one of my own biases, that tube amps are complementary to compression drivers and horns in some way that has not been fully explained (to paraphrase: because of the differences between the way tubes and solid state devices work).

I liked that he allowed as how he "still" didn't know why some electronics seem to have good sound stage depth and others do not.

I found his description of the 4660 horn design fascinating and also that the same ideas are included in the design of JBL's latest horns.

I have long wondered about the risk of doppler distortion in the Tannoy coaxial, but I had never before seen the problem addressed. He also seemed to suggest that the projecting treble coaxial horn is so fraught it is beyond problematic.

In talking about patents in audio and acoustics, he said that many recent patents have been awarded because of inadequate research of prior art and prior writings (Olsen in the 1920's) and that therefore the patents are not actually valid. He said that at JBL they sometimes thought it better to not patent something because then no one would know about it. He also said they did not try to protect some things they did because they were so expensive no one else would dare try to copy them—like close tolerances in compression drivers that led to yield problems, but making the gaps more relaxed caused frequency response anomalies which could not be remedied other ways. This makes me think of past conversations here about apparently unused drivers that people were buying on eBay.

He has worked to get time alignment and linear phase in his music system. Though he does not say this explicitly, I think that for him these are the persuasive possibilities of digital electronics past the front end sources. I liked that he notes differences in digital music products when that does not seem strictly possible in the digital domain; this is an old conversation between my son and me.

[Robh3606]

I found it interesting that he ditched the Everest cabinets, kept the drivers and made his own cabinets because the Everest cabinet was holding him back! Love to get a better look at the horn he is using and wonder if he is using the 045Be in his speakers. They look cool a stubby L250 like arrangement.

Rob :)

[Ian Mackenzie]

Glad you guys found this interview. I posted a link in another thread.

Greg 3 D printed those horns. The idea was to line up the sides horizontally with centre under the screen.

On the occasions when l have met Greg it’s his granular understanding drivers and being able to explain exactly what’s occurring in a system that’s truly impressive. For example Greg is able to interpret the limitations of modelling large drivers such as the 2245 and then adopt specific measurement techniques to find the answers. He tells it how it is too.

Greg is a world class loudspeaker engineer.

What l thought was interesting is that Greg adopted an empirical approach to initial testing of system and networks in a listening room early in the development as apposed to predictive modelling using driver data collected in a test chamber. Greg used his ears early on to determine if a system it was going to gel or not.

[DavidF]

I found it interesting that he ditched the Everest cabinets, kept the drivers and made his own cabinets because the Everest cabinet was holding him back! Love to get a better look at the horn he is using and wonder if he is using the 045Be in his speakers. They look cool a stubby L250 like arrangement.

Rob :)

OK, now, if you watch the camera pan the side wall you will see a woofer looking back at you from within the fireplace. Better use for a fireplace in So. Cal, I suppose.

[Robh3606]

Glad you guys found this interview. I posted a link in another thread.

Greg 3 D printed those horns. The idea was to line up the sides horizontally with centre under the screen.

On the occasions when l have met Greg it’s his granular understanding drivers and being able to explain exactly what’s occurring in a system that’s truly impressive. For example Greg is able to interpret the limitations of modelling large drivers such as the 2245 and then adopt specific measurement techniques to find the answers. He tells it how it is too.

Greg is a world class loudspeaker engineer.

What l thought was interesting is that Greg adopted an empirical approach to initial testing of system and networks in a listening room early in the development as apposed to predictive modelling using driver data collected in a test chamber. Greg used his ears early on to determine if a system it was going to gel or not.

Hello Ian

I have a couple of questions:

Is he using he 045Be or just running the 476Be all the way out. Could he be using a 476Mg??

What is the horn/waveguide based on?? Is it similar to the M2 where there is a constantly changing flare rate to reduce reflections?? Can't tell from the photo but it doesn't look that deep also like the M2/some PT waveguides. Is it symmetrical or asymmetrical vertical diffraction slot??

Any chance of better look at them say a picture??

Thanks Rob :)

[Mr. Widget]

I found it interesting that he ditched the Everest cabinets, kept the drivers and made his own cabinets because the Everest cabinet was holding him back! Love to get a better look at the horn he is using and wonder if he is using the 045Be in his speakers. They look cool a stubby L250 like arrangement.
I am not surprised GT took this path. While I loved my Everests, I struggled to get them to play nicely in several rooms that I put them in. When I upgraded to the DD67000 Everest woofers the bottom end was better, but they still didn't have the clarity of a single 2216ND in the M2. I am sure that Greg's custom speakers are sonically an upgrade.

While I love the aesthetics of the E2 series of Everests, my guess is that the spacing of the woofers and their height from the floor must have been the reason they were so difficult to get their best performance in so many rooms.

I really enjoyed Greg's discussing a number of points:

1. The "shopping mall live piano" demonstration of the importance of dynamics.
2. How power compression in testing will affect measurements.
3. His mention of the difference of opinion between the "Sean and Floyd guys" and his personal take on the importance of dynamics versus directivity.


Widget

[DavidF]

Yes, I would have liked to dive deeper on many points raised but it was also nice to hear from Greg after several years. I was fortunate to speak with him at the get-togethers hosted by Titanium Dome years back. Sounds like he has not lost his engineer's curiosity and willingness to engage new technology since leaving the Firm.

[Robh3606]

I am not surprised GT took this path. While I loved my Everests, I struggled to get them to play nicely in several rooms that I put them in. When I upgraded to the DD67000 Everest woofers the bottom end was better, but they still didn't have the clarity of a single 2216ND in the M2. I am sure that Greg's custom speakers are sonically an upgrade.

While I love the aesthetics of the E2 series of Everests, my guess is that the spacing of the woofers and their height from the floor must have been the reason they were so difficult to get their best performance in so many rooms.

I really enjoyed Greg's discussing a number of points:

1. The "shopping mall live piano" demonstration of the importance of dynamics.
2. How power compression in testing will affect measurements.
3. His mention of the difference of opinion between the "Sean and Floyd guys" and his personal take on the importance of dynamics versus directivity.


Widget


Hello Widget

I didn't realize the Everest's were difficult to integrate into a room. That does make sense though having the woofer's that low. Don't recall anyone complaining with 4435's but I do remember seeing several times they were up on stands.

The elevator music comment from a previous interview always had me wondering it makes more sense now. Interesting about sine sweep vs MLSA.

Yes there is something to be said about how relaxed and effortless dynamic speakers sound. I always liked the dynamics of the larger systems. I was a hold out on the large format drivers until I got a pair at home. Didn't think it would make a difference at the levels I listen at. Was I surprised when I hooked up the 476Mg's and got some listening time with them.

Rob :)

[Mr. Widget]

Was I surprised when I hooked up the 476Mg's and got some listening time with them. That's my take.

While the Revel Salons and the JBL M2's are both superior speakers in terms of directivity and measurements in general, to me they are less "real" than a properly executed system with a large 4" diaphragm compressions driver. The 476Be and 476Mg being pretty much the top of the heap.

Not to say that a cone and dome system can't sound amazing and many do. However when done right the better compression driver systems can sound just a little more "real".


Widget

[Mr. Widget]

Some highlights for me:

I love it, in the context of the old penchant for Bose-bashing in these forums, that GT seemed intrigued by the basic idea of the BOSE 901 and said that if the shortcomings had been addressed, it could have become quite an interesting speaker. That is: 1) use higher quality drivers; 2) provide some decent-sounding electronics in the EQ box; 3) change the front single driver into a two-way with a tweeter because there is no way to get any decent treble by EQ'ing a five-inch full range.

I liked hearing GT confirm one of my own biases, that tube amps are complementary to compression drivers and horns in some way that has not been fully explained (to paraphrase: because of the differences between the way tubes and solid state devices work).

I liked that he allowed as how he "still" didn't know why some electronics seem to have good sound stage depth and others do not.

I found his description of the 4660 horn design fascinating and also that the same ideas are included in the design of JBL's latest horns.

I have long wondered about the risk of doppler distortion in the Tannoy coaxial, but I had never before seen the problem addressed. He also seemed to suggest that the projecting treble coaxial horn is so fraught it is beyond problematic.

In talking about patents in audio and acoustics, he said that many recent patents have been awarded because of inadequate research of prior art and prior writings (Olsen in the 1920's) and that therefore the patents are not actually valid. He said that at JBL they sometimes thought it better to not patent something because then no one would know about it. He also said they did not try to protect some things they did because they were so expensive no one else would dare try to copy them—like close tolerances in compression drivers that led to yield problems, but making the gaps more relaxed caused frequency response anomalies which could not be remedied other ways. This makes me think of past conversations here about apparently unused drivers that people were buying on eBay.

He has worked to get time alignment and linear phase in his music system. Though he does not say this explicitly, I think that for him these are the persuasive possibilities of digital electronics past the front end sources. I liked that he notes differences in digital music products when that does not seem strictly possible in the digital domain; this is an old conversation between my son and me.+1 on all counts.

Specifically on the 901, the original used the same CTS 4.5" full range speaker that were used in the original Auratones. They were inexpensive little speakers that did not suck... and since there was no crossover with all of the phase shift and other issues associated with a multi-way speaker, there was a certain purity there. The 901s took this in an interesting direction. As GT pointed out using better electronics and adding a small tweeter to the front speakers could have been quite interesting.

It was interesting to hear Greg's openness to unusual designs like the 901s and his discussion regarding the Carver open backed design.


Widget

[hjames]

I just found this interview on Erin's Audio Corner on YouTube.
https://www.youtube.com/watch?v=afeTHLLp-EI
Very nice! The redesigned Everest speakers were interesting.
I'd like to know what the ceiling drivers were that he refers to with the dual 5" drivers and "toy horns" (mylar-like but not mylar diaphragms) ...

[Mr. Widget]

Very nice! The redesigned Everest speakers were interesting.
I'd like to know what the ceiling drivers were that he refers to with the dual 5" drivers and "toy horns" (mylar-like but not mylar diaphragms) ...Here ya go... take a look at the wave guide. It is a mini original Everest/S3100 type wave guide.

https://www.jblsynthesis.com/products/loudspeakers/SCL-7.html?dwvar_SCL-7_color=Black-AM-Current&cgid=loudspeakers


Widget
.

[Ian Mackenzie]

Hello Ian

I have a couple of questions:

Is he using he 045Be or just running the 476Be all the way out. Could he be using a 476Mg??

What is the horn/waveguide based on?? Is it similar to the M2 where there is a constantly changing flare rate to reduce reflections?? Can't tell from the photo but it doesn't look that deep also like the M2/some PT waveguides. Is it symmetrical or asymmetrical vertical diffraction slot??

Any chance of better look at them say a picture??

Thanks Rob :)

I have passed on your request

[rusty jefferson]

...I really enjoyed Greg's discussing a number of points:

1. The "shopping mall live piano" demonstration of the importance of dynamics.
2. How power compression in testing will affect measurements.
3. His mention of the difference of opinion between the "Sean and Floyd guys" and his personal take on the importance of dynamics versus directivity.
Widget
4. Linear Phase digital crossover filters and time alignment.

Let's not bury the lead. Greg built (essentially) a diy Everest system with components he personally designed and chose to use DEQX crossovers not just for the Everest but also the K2 in his system. That seems like high praise indeed.

I remember reading this thread (http://www.audioheritage.org/vbulletin/showthread.php?29281-Some-thoughts-on-Deqx-and-their-products&highlight=Deqx) started by Ken Pachkowsky about his experience with the DEQX and at the time thinking "this is unlikely". But recently I met this fellow Ken mentions and got to watch him tune a custom 3 way. My friend who built the system is an experienced audio engineer who designs and builds good equipment, is very competent in all things audio, and regularly writes for an audio magazine. He worked a long time with the DEQX software and barely got the system to the point of being listenable. In just a few hours, this DEQX tech had that system sounding amazing. It was something to see/hear. Perhaps Greg is as good using the software or maybe even uses the fellow to help tune the system? I'd be curious to know.




...I and others on this forum have invested countless hours into tweaking a Deqx setup. I would bet most Deqx owners have never heard their system with the Deqx properly tuned? It's only in the last year that I met someone who has an intimate working knowledge of the Deqx Architecture and Software well enough to set it up properly. We setup an internet client so he could take over my pc remotely. I simply setup the microphone where I was told. In a few hours he had it sounding better than it ever had. I wish you could all be here to hear the difference.

I was so impressed with what he had done I arranged an audition of the HD3 system at Westlake Audio. Both of us met in LA and spent 2 days at Westlake Audio. To say the techs at Westlake were impressed is an understatement. For the demo a miss-matched pair of LC8.1’s combined with a Westlake custom subwoofer system were placed in the sound room. A series of measurements were taken and custom correction filters were created with the Deqx software. The correction filters had illiminated the miss-match problem. We then created a set of three room correction filters, each using slightly different crossover points. These were merged with the correction filters and stored in three different profiles. During the listening tests we could switch between the profiles by selecting each one with one click of the remote. The Westlake techs were astonished, stating the system was sounding as good as or better than anyone heard before. This is no small feat. Tuning a Westlake system normally takes several weeks with constant hardware tweaks being done to the passive internal networks. Dozens of man hours go into this process.

The fellow who did the setup understands the nuances of the Deqx software and interprets the resulting data “differently” than anyone else I have seen. The subsequent filters he builds are truly amazing and certainly show what this tool is capable of when used properly.
For those of you that have owned and already have disposed of a Deqx (I know there are many) it’s unfortunate.

For those that have not tried one....go for it....but only if you’re prepared to spend a few hundred bucks setting it up right. I promise you will not regret it.:D

I would be happy to share the gentleman's contact info on a person to person basis. I don't think I should be posting his name here. ...

[Mr. Widget]

4. Linear Phase digital crossover filters and time alignment.

Let's not bury the lead. Greg built (essentially) a diy Everest system with components he personally designed and chose to use DEQX crossovers not just for the Everest but also the K2 in his system. That seems like high praise indeed.

I remember reading this thread (http://www.audioheritage.org/vbulletin/showthread.php?29281-Some-thoughts-on-Deqx-and-their-products&highlight=Deqx) started by Ken Pachkowsky about his experience with the DEQX and at the time thinking "this is unlikely". But recently I met this fellow Ken mentions and got to watch him tune a custom 3 way. My friend who built the system is an experienced audio engineer who designs and builds good equipment, is very competent in all things audio, and regularly writes for an audio magazine. He worked a long time with the DEQX software and barely got the system to the point of being listenable. In just a few hours, this DEQX tech had that system sounding amazing. It was something to see/hear. Perhaps Greg is as good using the software or maybe even uses the fellow to help tune the system? I'd be curious to know.I also loved his referring to the "rock on the end of a stick" :D

I have no doubt that his custom E3 Everests are outstanding. There is no getting around it, the man has years of experience, great ears (or at least ears that hear in a way the I tend to agree with), access to drivers, test, and playback equipment that not everyone of us does... what is not to love!

Regarding DEQX, his mentioning the next generation DEQX which is apparently just now becoming available definitely has me interested it giving them another try.


Widget

[Ian Mackenzie]

Good point.

Greg has been using DEQX a long time and has considerable depth of expertise in crossover network design.

It wasn’t straight forward though. None of this is about clicking your fingers no matter what anyone says.

Greg originally used two Pass Labs XVR1’s. Then modified them to improve the transparency bypassing circuit coupling capacitors and hard wiring some of the switches. That’s a long and at times frustrating problem working with Nelson Pass. Pass is purely focused on experimenting with power amp active devices.

Greg then started using DEQX and found the DA converters and output op amp buffers the weak link and installed high end Meitner outboard DA converters. I understand DEQX has upgraded the software which Greg says is an improvement. Greg’s system is really complicated now. When we tested a prototype analogue active crossover we were developing it was a long procedure changing the cabling. It took half an hour. Luckily it worked really well.

For someone like Greg with his expertise DEQX is a great loudspeaker developer tool.

The next Gen DEQX is looking upward of AUD $7500.00. With a lot of hand holding it would be okay and l think DEQX did that at one stage. But what you don’t know you don’t know and it’s a hard lessen finding that out.

[rusty jefferson]

...For someone like Greg with his expertise DEQX is a great loudspeaker developer tool...

I think the point Ken was making, and I witnessed is you don't need to know Jack about the software. The DEQX comes with one of these "tuning" sessions included in the cost. A user, except maybe someone like Greg, isn't going to get it sounding any better than this fellow who sets it up. Just leave it alone and listen to music. :)

[Ian Mackenzie]

I think the point Ken was making, and I witnessed is you don't need to know Jack about the software. The DEQX comes with one of these "tuning" sessions included in the cost. A user, except maybe someone like Greg, isn't going to get it sounding any better than this fellow who sets it up. Just leave it alone and listen to music. :)

I do remember those fun times. Ken was very, very passionate about his Westlake system and his 4345's before that. Like many of us that passionate leads to excessive exadgeration which is all part of this hobby.....Lol. That's the other thing. What's better to you may or may not be liked by the next guy or the next guy after that. That's what makes audio sound reproduction so unique.

"What comes out of any loudspeaker is never going to match a live performance". Greg makes that point. But it can become a life long obsession.

There’s are no absolutes in this business. Some stuff focuses on one element of sound reproduction at the expensive of all else and people still pay a lot of money for it. The Klipschorn is an example of that and they are still being made. Klipsch is a big company these days. Vandersteen is at the other end of the spectrum.

You get used to what you have!

[sebackman]

Interesting interview and I like the form that Erin provide the time to actually explore different topics. In a world where everything is 2-minute sound bites this is refreshing.

He has also done interviews with Sean Olive and Floyd Toole that I find very interesting. Well worth a listening.

It would be very interesting to find out what settings Mr. Timbers uses in the DSP for both the home brewed Everests and his S9900. I understand that he uses FIR filters but XO points and corrections would be very interesting to see.

[hjames]

Here ya go... take a look at the wave guide. It is a mini original Everest/S3100 type wave guide.

https://www.jblsynthesis.com/products/loudspeakers/SCL-7.html?dwvar_SCL-7_color=Black-AM-Current&cgid=loudspeakers

Widget

Thank you!
Looks like it may be related to the JBL HDI-1600, which is available in a walnut finish
https://www.jbl.com/bookshelf/HDI-1600.html

and also uses that 2410H-2 1" compression driver. (Greg said it had mylar-like but not mylar diaphragms)
At $990 a pop, price is approaching the $1,100 InWall Synthesis SCL-7s ...

[BMWCCA]

Looks like it may be related to the JBL HDI-1600, which is available in a walnut finish
https://www.jbl.com/bookshelf/HDI-1600.htmlWow! Those little suckers are nearly a thousand-dollars each.

[rusty jefferson]

...I love it, in the context of the old penchant for Bose-bashing in these forums, that GT seemed intrigued by the basic idea of the BOSE 901 and said that if the shortcomings had been addressed, it could have become quite an interesting speaker. That is: 1) use higher quality drivers; 2) provide some decent-sounding electronics in the EQ box; 3) change the front single driver into a two-way with a tweeter because there is no way to get any decent treble by EQ'ing a five-inch full range....

So, since there's interest in this I'll share an article written by a fellow I met last winter who said he'd been inspired by the Bose 901 many years ago and has been on the path to improve the concept ever since. He'd had many conversations with Dr Bose about it over the years as well as other audio engineering friends.

After reading the article and discussing it with my audio gurus, I thought his system would be just as smeared (or worse) as the 901s but would probably have better dynamics. Our biases poison us. His system fixed exactly the problems discussed about the 901s and created the most natural full range 3 dimensional soundstage accurately placing the musicians across the stage I've ever heard, barring one other system. Any recording of a live acoustic event spanned the entire width of the room (24 feet) and has as much depth and most important, as much imagine specificity as the microphones captured. And the dynamics were through the roof. Like a cinema experience. High sound pressure, low distortion, and absolutely transparent sound. You cannot tell there's even speakers in the room. I was stunned. No smear. Clean and clear, with excellent transients. Not a perfect system, but shockingly good. Most interesting, is that there is no change to the image or soundstage when the center speaker is turned off/on. Just more dynamic headroom when on.

I reached out to him this morning to see if it's okay to share the article. For anyone seriously interested, he's always happy to discuss the design. Let me know and I'll put you in touch. If you're in the area (Tampa) he'll probably invite you to listen to it.

https://drive.google.com/file/d/1YXxwphabbgOkZQfNISj_Fmd2T_sZRYNc/view?usp=sharing

[Mr. Widget]

Thanks Rusty!

I quickly read through bits of the article and then downloaded it.
I'd like to spend more time with it when I am not on the clock... solving and creating other audio problems. :D


Widget

[DS-21]

Here ya go... take a look at the wave guide. It is a mini original Everest/S3100 type wave guide.

https://www.jblsynthesis.com/products/loudspeakers/SCL-7.html?dwvar_SCL-7_color=Black-AM-Current&cgid=loudspeakers


Widget
.


Are you sure? He said they were from Pro and used the same compression driver as his 5-series.

[Mr. Widget]

Are you sure? He said they were from Pro and used the same compression driver as his 5-series.Nope, not sure… but I am fairly certain it is the correct model.


Widget

[Ian Mackenzie]

From the spec sheet

High Frequency Driver
1" (25 mm) 2410H-2 Teonex annular ring-diaphragm compression driver- mini compression driver

Not Mylar but used for the same reasons

[DS-21]

Nope, not sure… but I am fairly certain it is the correct model.


Widget

I'm pretty sure that's not the model.

Going back to the video the speakers are under square grilles, not rectangular grilles. See at 4:58 in Erin's video.

90599

Maybe they're SCL-3's, and he's simply mistaken about the horn pattern.

[srm51555]

Thanks Champster for posting this and thanks Ian for posting it in the other thread as well. I thought it was super cool he took the time to meet and answer all of those questions off the cuff. It seems like he is a humble person even though he has designed all of these great systems.



1. The "shopping mall live piano" demonstration of the importance of dynamics.
2. How power compression in testing will affect measurements.
3. His mention of the difference of opinion between the "Sean and Floyd guys" and his personal take on the importance of dynamics versus directivity.


Also agree. His take on dynamics versus directivity makes total sense. I also didn't know constant directivity and how lively a room sounds played together. I assumed the opposite was true.

One of the neat parts about LHF is that you can lurk undetected, but still see all of the content. I did this for years while in college until finally signing up, so if you happen to take a look at this thread Greg, thanks for taking the time to do the interview and many other years of answering questions through other members. Glad to see you still have the passion of building and I hope all is well.

Thanks,
Scott

[Ian Mackenzie]

I have a follow up on Greg’s system below for you guys. Greg now spends most of his time on his house boat enjoying his retirement. So snippets about his system are few and far between.

Hi Ian,

“For your amusement, I have attached pictures of my system below. I have 2 15”s and a 4” compression driver per channel. My Sub is a DCD 18” mounted in my fireplace (blocked off). Everything is sealed, neither 15 is rolled off on the low end. The 18, and both 15’s all extent from the room cutoff at 13 Hz up to their respective roll of points of 80 Hz, 150 Hz and 750 Hz. The system uses linear phase crossovers and has no group delay. The Impulse response shows the alignment. The only reason there is a lift before the main spike is that the Sub has a much wider impulse: and that is what you see preceding the main spike.”

The thing is Greg’s system is a constant work in progress. On each occasion l’ve heard it the system has become progressively more complex.

I don’t know the reason for the new enclosures or details of the horn. It was made in Greg’s impressive workshop using a 3D printer. Last l heard Greg was Beta Testing the latest DEQX software which Greg said was a big improvement. No idea where DEQX is with that.

If l can glean any more on Greg’s system l will.

Ian

PS. I would be surprised if there isn’t a neat active solution for the 4367. I have asked the question.

[grumpy]

Thanks Ian,

Always nice to see what's cooking in the kitchen :)

[Ian Mackenzie]

Greg suggested the following for the 4367.

I’ve relayed it to the 4367 owner in Italy with some pointers on obtaining the woofer voltage drive using a Focusrite Scarlet USB interface. It’s up to him now.

https://www.audioheritage.org/vbulletin/showthread.php?37497-Jbl-4367&p=384175&viewfull=1#post384175

On paper the schematic above is a 3rd order low pass filter but the tech sheet voltage drive is closer 4th order LR -6 db 550 hertz and -24 db 1100 hertz. Measurements at the driver terminals are the most accurate way of measuring the voltage drive. That’s my educated guess.


From GT:

Ian,

I did not spend any time active on the 4367. However, his suggestion of direct driving the woofer and using the passive HF network is good. He could also drive both drivers directly with the crown. I would suggest a 10 db resistor pad on the HF. It will be too noisy to drive directly and a bit dangerous. Should be pretty easy to do.
Sent from my iPad.

[turnitdown]

https://www.youtube.com/watch?v=zDc25x0Zo_o

[BMWCCA]

https://www.youtube.com/watch?v=zDc25x0Zo_o

Thanks.
They need to chip in and buy Greg a better computer/camera!

[Robh3606]

Thanks.
They need to chip in and buy Greg a better computer/camera!

And the drop outs!

Rob :)

[turnitdown]

I found many interesting points in the second one, including, but not limited to - the synergy of tubes and CDs, invest in a great woofer, his preference for wider dispersion. There was more...and yes, the dropouts were a bit annoying. His endorsement of DSP (to a degree) may nudge me toward a Mini DSP.

[DerekTheGreat]

Finished the first, making my way through the second one. "Shiver me Timbers". I appreciate that he's got a sense of humor, struck me as one of those guys who is always down to business or doing something. I too, am leaning more toward a Mini DSP. It's nice to know he's on the time-alignment board and that there was a discussion of coax drivers. Shame those KEF speakers came up. Then again, so did Blose. Funny how they discussed "hot-rodding" a set of 901's, right down to changing the terrible components in both the crossover and the cabinets. Well, that's what makes a Bose a Blose. :lol_fit: ...if you put all that work into a set of 901's, they'd no longer be Blose..

[Robh3606]

I found many interesting points in the second one, including, but not limited to - the synergy of tubes and CDs, invest in a great woofer, his preference for wider dispersion. There was more...and yes, the dropouts were a bit annoying. His endorsement of DSP (to a degree) may nudge me toward a Mini DSP.


I was surprised about the horns as well. First the 120 degree dispersion and how the Array was basically a "stock" horn and he would have preferred a wider pattern over the 80 x 80. Also about how the horizontal slot was "wrong" and how he has incorporated vanes in his diffraction slot to help even out the vertical pattern so it is as smooth as the horizontal.

Also with comparison's to the M2 and 4367 about how "harsh" the stock M2 electronics are compared to what could be used with the 4367.

A lot of good info in there.

Rob :)

[Earl K]

Hi,

I'm glad that you all mentioned the 120deg horizontal dispersion of GT's custom printed horn ( after seeing the pic of his current system I was left wondering "where-had-I-seen-that-horn-profile-before??"

Here it is ( in brochure form )

It's gratifying to see GT revisiting some of these past ideas ( and not shying away from the diffraction slot simply because of the current "koolaid".

:)

[Robh3606]

Hello Earl

Go to the first interview. 1:06 and keep going to 1:12. He has symmetrical 120 X 120! He shoots for 90-120 patterns. Plus the printing and vane description start at 1:04 in the second.

Rob :)

[Earl K]

Thanks for those times Rob ( I hadn't yet gotten to those points ).

:)

[Mr. Widget]

Thanks for those times Rob ( I hadn't yet gotten to those points ).

:)+1

I actually lost interest and stopped watching. I'll give it another go.


Widget

[BMWCCA]

+1

I actually lost interest and stopped watching. I'll give it another go.I am only able to take just so much of the interviewer!

In the first interview I laughed because he didn't know any asymmetrical JBL models and had never heard of a 250.
You may have noticed that Greg staged himself in front of his black 250ti for the second interview but said nothing about them. :D

[Robh3606]

I am only able to take just so much of the interviewer!

In the first interview I laughed because he didn't know any asymmetrical JBL models and had never heard of a 250.
You may have noticed that Greg staged himself in front of his black 250ti for the second interview but said nothing about them. :D

Yeah and he didn't asked about them? Go figure? They are even the same shape as his current speakers? They did come up when they were discussing the effectiveness of radius's vs diffraction with 2" being the minimum vs the 1 inch on the 250's but that's it.

Rob :)

[turnitdown]

I did notice (and was a bit chagrined by) Erin's lack of knowledge, or preparation for the interview, but I have followed all things JBL for longer than he's been alive, well, maybe not that long. Can't blame him though. Although the interviews provoked many questions on my part.

[BMWCCA]

I did notice (and was a bit chagrined by) Erin's lack of knowledge, or preparation for the interview, but I have followed all things JBL for longer than he's been alive, well, maybe not that long. Can't blame him though. Although the interviews provoked many questions on my part.Yeah, in the first interview, Greg showed him his current speakers and that's where the interviewer asked how he came up with the asymmetrical design and Greg mentioned the 250.

Second interview the 250s are sitting right there the whole time. :banghead:

[Robh3606]

Yeah, in the first interview, Greg showed him his current speakers and that's where the interviewer asked how he came up with the asymmetrical design and Greg mentioned the 250.

Second interview the 250s are sitting right there the whole time. :banghead:

You know thinking about it. We are probably the worst to judge on JBL knowledge. How many years have we been here talkin about JBL lore?

Is there anything we haven't discussed to death?

Rob :)

[DerekTheGreat]

+1

I actually lost interest and stopped watching. I'll give it another go.


Widget

Have it playing in the background while you're doing something else, what I did. No way I could've just sat & listened to them both. Much of the material covered in the interviews went right over my laymen head, but I'd perk up when they got to talking about "this speaker vs that one" type of stuff.


I am only able to take just so much of the interviewer!

In the first interview I laughed because he didn't know any asymmetrical JBL models and had never heard of a 250.
You may have noticed that Greg staged himself in front of his black 250ti for the second interview but said nothing about them. :D

It's not just me then. I had a bit of a hard time with that dude too.


Yeah, in the first interview, Greg showed him his current speakers and that's where the interviewer asked how he came up with the asymmetrical design and Greg mentioned the 250.

Second interview the 250s are sitting right there the whole time. :banghead:

Yep, isn't that something? Although in the first interview, I thought Greg said he no longer had 250ti's?


You know thinking about it. We are probably the worst to judge on JBL knowledge. How many years have we been here talkin about JBL lore?

Is there anything we haven't discussed to death?

Rob :)

Well, I know the 250's and even some of the 43xx models and I've only been lurking around here for a few years. Come to think of it, before I came on here, I knew the 250's, L150A's and L220's. I want to say I knew a whiff of the 250's, not entirely sure. So to put it in perspective, that dude is older than me and is running his own YouTube channel dedicated to audio. No excuse not to know better or as others have said, do his homework before interviewing a legend.

On a side note, it's too bad no one asked him about the 250ti vs the XPL200. Would've been cool if the UREI monitors were brought up in their coax discussion. I suppose one could argue that Greg did touch on them by saying he didn't really pay attention to products he wasn't involved with. They did touch on issues present with coax drivers, and perhaps that's why Greg hasn't bothered with them. Or did he?

[Robh3606]

Well, I know the 250's and even some of the 43xx models and I've only been lurking around here for a few years. Come to think of it, before I came on here, I knew the 250's, L150A's and L220's. I want to say I knew a whiff of the 250's, not entirely sure. So to put it in perspective, that dude is older than me and is running his own YouTube channel dedicated to audio. No excuse not to know better or as others have said, do his homework before interviewing a legend.

On a side note, it's too bad no one asked him about the 250ti vs the XPL200. Would've been cool if the UREI monitors were brought up in their coax discussion. I suppose one could argue that Greg did touch on them by saying he didn't really pay attention to products he wasn't involved with. They did touch on issues present with coax drivers, and perhaps that's why Greg hasn't bothered with them. Or did he?

I can see your point. We are primarily a vintage site and most the questions except for preference of 4343, 4345, 4355 were more focused on what's available now.

WRT prep work I did a search for Greg Timbers Interviews and there are plenty so yes he could have pulled them up and went trough them but he didn't.

Still good stuff though

Greg had a pair of prototype XPL 250's don't know if he still does.

There is a comparison between the 4315 and XPL-200 on the site https://www.audioheritage.org/vbulletin/showthread.php?10615-4315B-Includes-Designer-s-Post

He has one with Geedes I want to watch.

Rob :)

[DerekTheGreat]

Thanks Rob!

I didn't realize there are more interviews with Greg out there, that's rad. I forgot all about Greg's thoughts on the 4315 vs XPL200! I do recall reading that at some point. As a former XPL200 owner, I concur about his assessment of the "fluffy" midbass, lack of kick from the 2214, needing to biamp and the killer midrange. The midrange presentation was my favorite part of those speakers.

[Ian Mackenzie]

Interesting interview and I like the form that Erin provide the time to actually explore different topics. In a world where everything is 2-minute sound bites this is refreshing.

He has also done interviews with Sean Olive and Floyd Toole that I find very interesting. Well worth a listening.

It would be very interesting to find out what settings Mr. Timbers uses in the DSP for both the home brewed Everests and his S9900. I understand that he uses FIR filters but XO points and corrections would be very interesting to see.

I will see what l can find out.
I’m pleased you could see the positives and l agree completely. It was an informal chat.


Greg doesn’t mince words and gets straight to the point. I think that’s what came across in that discussion. There’s no magic. It’s about well designed drivers (the woofers) and making the right decisions about a system at different price points. Some systems are a surprise as it turns out.

The key point about the new horn is the vertical diffraction slot.

I also agree it’s fun watching the content like ants eating a scrap of food on the floor. They come from everywhere fighting over a scrap trying to get a word in.

On the crossover Greg is a beta tester of the new advanced 8 output model. I received an email from DEQX this week announcing the final release of beta product at US$6,995.00. The GUI is no where near ready according to Greg and it will be at least 6 months before any further updates. Wait for it. The MRRP will be a wallet burning US$15,000.00 for the model with X active and 8 outputs. The market for this thing is hi end exclusive loudspeakers using the DEQX platform.

Btw I’ve often had drop outs with Teams. I depends on a number of factors including the load on the network and the available bandwidth.

[DS-21]

I did notice (and was a bit chagrined by) Erin's lack of knowledge, or preparation for the interview, but I have followed all things JBL for longer than he's been alive, well, maybe not that long. Can't blame him though. Although the interviews provoked many questions on my part.Kinda odd to knock Erin for not knowing about something that might have been new when he was three, but complete silence about Timbers’ mistakes about the dispersion pattern of the speakers he uses for heights. He originally claimed they were angled like the current Synthesis ceiling speakers, but later called them out as SCL-3, which is not.

[BMWCCA]

Kinda odd to knock Erin for not knowing about something that might have been new when he was three, but complete silence about Timbers’ mistakes about the dispersion pattern of the speakers he uses for heights. He originally claimed they were angled like the current Synthesis ceiling speakers, but later called them out as SCL-3, which is not.

Don't make excuses for the unprofessional behavior of the interviewer.
If you know anything about the subject of your interview, you owe it to yourself and your chosen role to know as much as you can. It would seriously be hard to even Google Greg and not find his affinity and responsibility for the L250—if not his own current and personal asymmetric design—had one been doing even a reasonable amount of homework. Then to the comment that you've never seen an asymmetrical speaker system would never have stuck out as such an ignorant statement.

Even when given a second chance in Part Two with the 250ti right next to Greg, it didn't come up at all. And I'm not just shocked as a 250ti owner, but rather stunned as someone interested in Greg Timbers by the apparent shallowness of the interviewer and his obvious lack of scholarship on his chosen subject. That's really a minimal expectation.

This is likely to have little effect on the situation in Gaza or Ukraine, but it is still irritating within our little microcosm here.

[1audiohack]

You could ask Erin for your money back. ?

Barry.

[Mr. Widget]

You could ask Erin for your money back. ?

Barry.:applaud: :rotfl: :applaud:


Widget

[BMWCCA]

You could ask Erin for your money back. ?

Barry.Certainly a good point. I did get what I paid for.

I don't suffer know-it-alls with little knowledge very well! Possibly because I am one, too?

[Robh3606]

Certainly a good point. I did get what I paid for.

I don't suffer know-it-alls with little knowledge very well! Possibly because I am one, too?

And how many years have you been here and didn't your farther leave you some JBL''s you still have and appreciate? It's all about perspective and like me your are vintage oriented.

You have someone who has measured many of the current systems and that is what he is focused on.

There was a lot of good info in both interviews. If he didn't take the time we wouldn't have it.

So what's the harm?

Rob ?

[Ian Mackenzie]

It’s amusing that while both Erin and Greg decided to keep it informal and see where the discussion went you guys have nothing more important than to pointlessly dissect it.

They both correspond privately. Erin is not a JBL groupie and that’s why Greg agrees to do live Vids with Erin even on a casual basis.

It’s almost as bizarre as what this interview reveals.


https://youtube.com/watch?v=JxQ97AlgHMk&si=sDCHokc99YxjYNYI

[DerekTheGreat]

You could ask Erin for your money back. ?

Barry.

:rotfl:

Great way to put it back into perspective. Alternatively, we could have zero interviews out there. It's nice to know Greg is still willing to talk about former products/projects. Would be cool if he came back on here, even just to post and never comment or reply. I heard something happened years ago and so now he avoids this place.

[srm51555]

I also appreciate both for taking the time for the interview. I learned a couple things and it gave me a couple of things to think about.

[BMWCCA]

And how many years have you been here and didn't your farther leave you some JBL''s you still have and appreciate? It's all about perspective and like me your are vintage oriented.

You have someone who has measured many of the current systems and that is what he is focused on.

There was a lot of good info in both interviews. If he didn't take the time we wouldn't have it.

So what's the harm?I won't say I didn't enjoy seeing Greg get the exposure he deserves. Apologies for focusing on the negative. I should have realized the backlash being a discontent among all the discontents here would engender. ;)

My (brief) ten-year career as an automotive journalist between my 20- then 14-year stints in BMW sales started with my constantly bringing attention to errors-of-fact in my beloved magazine. So I was hired first as a proof-reader ending that vocation as Managing Editor and feature writer. The errors-of-fact that now plague that mag I attribute to them just not caring or hiring someone without knowledge of the subject matter. So I guess I come by the critic role somewhat as second nature.

Can't say I don't get a giggle when I'm reading an article about vehicle mods to the few remaining manual-transmission models out there and see the coverage talking about "short-shitters".

But when even Ian starts complaining about complainers and resorts to political news-clips for emphasis—I know we've carried this too far!
I also know sometimes the truth hurts!
:cheers:

[grumpy]

Glad Mr. Timbers has the demeanor to take the questions and opportunities such as this in stride, and folks get to glean from it whatever's useful at their interest/skill level. :)

[Ian Mackenzie]

I won't say I didn't enjoy seeing Greg get the exposure he deserves. Apologies for focusing on the negative. I should have realized the backlash being a discontent among all the discontents here would engender. ;)

My (brief) ten-year career as an automotive journalist between my 20- then 14-year stints in BMW sales started with my constantly bringing attention to errors-of-fact in my beloved magazine. So I was hired first as a proof-reader ending that vocation as Managing Editor and feature writer. The errors-of-fact that now plague that mag I attribute to them just not caring or hiring someone without knowledge of the subject matter. So I guess I come by the critic role somewhat as second nature.

Can't say I don't get a giggle when I'm reading an article about vehicle mods to the few remaining manual-transmission models out there and see the coverage talking about "short-shitters".

But when even Ian starts complaining about complainers and resorts to political news-clips for emphasis—I know we've carried this too far!
I also know sometimes the truth hurts!
:cheers:

Hi Phil,

Hey l acknowledge your thought & I appreciate your sensitivity.

No offence taken or meant. I now get your lens.

The problem with this medium is the lack of sentiment.

When something is dropped and Greg agreed to it being passed on my recommendation is that Rob keeps the thread focused on that information and nothing else.

PS. How is that new house of yours going music wise?

Cheers

Ian