Double Stack ESS AMT-1 with Wings--Possible Kit for Heritage

[hallcon83]

Thanks  Chris for the explanations , I had asked the Speaker designer some question about a some of the different designs I was thinking of building, including the stacked AMT's , And all of his replies back about the different designs were that  --- Basically none of it would ever work ,

 

then I had said that I was planning to buy some measurement equipment, and find a decent active crossover like a miniDSP,  or Behringer ,  dbx, etc. , to try different crossover designs to narrow things down before committing to maybe then buying some final passive crossover parts.

 

 but he said  ---  No that doesn't work Active filters use text book slopes. I have never seen a speaker yet that will work with a text book slope crossover.

 

----  his answers depressed me for 2 days.... LOL - LOL 

 

[Rudy81]

14 minutes ago, hallcon83 said:

Thanks  Chris for the explanations , I had asked the Speaker designer some question about a some of the different designs I was thinking of building, including the stacked AMT's , And all of his replies back about the different designs were that  --- Basically none of it would ever work ,

 

then I had said that I was planning to buy some measurement equipment, and find a decent active crossover like a miniDSP,  or Behringer ,  dbx, etc. , to try different crossover designs to narrow things down before committing to maybe then buying some final passive crossover parts.

 

 but he said  ---  No that doesn't work Active filters use text book slopes. I have never seen a speaker yet that will work with a text book slope crossover.

 

----  his answers depressed me for 2 days.... LOL - LOL 

 

 

In my long journey to find a set of speakers I truly loved, I have tried many, many things.  I too heard all sorts of 'you can't do that' and 'that won't work'. What I have found is that there is no harm in trying various configurations and setups.  They may not work, but you will learn a lot about audio along the way. 

 

The staked AMTs with wings DO WORK.  They still sit in my listening room and I have had no desire to tinker with anything else.  I also use dual 18" OB for woofers, and many say they won't work either for good bass.  I disagree. 

 

Enjoy the journey!

[Chris A]

1 hour ago, hallcon83 said:

...No that doesn't work Active filters use text book slopes. I have never seen a speaker yet that will work with a text book slope crossover...

I don't use the crossover filters in the DSP crossovers, BTW.  I use PEQs around the crossover region to create the crossover slopes without adding phase growth across the crossover filter regions.  It turns out, this is very audible.

 

The other portion of his response implies something that I find odd:  if he is talking about perfect summing of the upper and lower crossover filters without requiring any input PEQs to smooth and flatten the crossover interference band, then he's got other issues (speaking bluntly).  I find that anyone that says that sort of thing really needs to take another engineering course or two (or maybe a fistful more) because he has misunderstood what it is that he needs to achieve.  That's what the input channel PEQs are meant to correct in DSP crossovers.

 

He's certainly not talking about using FIR filters.

 

Chris

[geoff.]

32 minutes ago, Chris A said:

I don't use the crossover filters in the DSP crossovers, BTW.  I use PEQs around the crossover region to create the crossover slopes without adding phase growth across the crossover filter regions.  It turns out, this is very audible.

 

 

So no 12db/octave (or whatever) slope?

 

You “just” EQ out the before/after and fine tune it?

[Chris A]

Yes.  Here is the result:

 

https://community.klipsch.com/index.php?/topic/182419-subconscious-auditory-effects-of-quasi-linear-phase-loudspeakers/page/3/&tab=comments#comment-2379562

 

and here is the process described:

 

https://community.klipsch.com/index.php?/topic/182419-subconscious-auditory-effects-of-quasi-linear-phase-loudspeakers/page/4/&tab=comments#comment-2388972

 

Chris

[geoff.]

brilliant, simply brilliant

 

and thanks, as always, for your selfless devotion to the truth!

 

 

[Rudy81]

50 minutes ago, Chris A said:

Yes.  Here is the result:

 

https://community.klipsch.com/index.php?/topic/182419-subconscious-auditory-effects-of-quasi-linear-phase-loudspeakers/page/3/&tab=comments#comment-2379562

 

and here is the process described:

 

https://community.klipsch.com/index.php?/topic/182419-subconscious-auditory-effects-of-quasi-linear-phase-loudspeakers/page/4/&tab=comments#comment-2388972

 

Chris

 

Took me a little bit to get Chris' technique down, but it works very well indeed. 

[Thaddeus Smith]

So I moved my equipment to a new rack a few weeks ago and I misconnected a couple drivers - the left bass bin was wired right side and I think the right tweeter was on the left. Music played, but I could tell it was off.

 

So my hearing isn't shot and I can discern anomalies.

 

In spite of my poor room design and acoustics, and after dialing in the active xo, these sound really good. I've also heard the setup in an entirely different room and configuration and they sounded great there.

 

So whatever combing effects exist, they certainly aren't discernable to the point of distraction.

 

This kind of stuff can certainly turn into a battle royal of "who's opinion do I trust?", but I'm fairly certain that no one who's gone through the effort here has hated the end result. To be fair, the current sampling of people also has varying degrees of tinkering and implementation of non-oem equipment up to and including esoteric levels.

 

Klipsch does a lot of things right, but I've grown to understand that they're not the end-all be-all solution either. My system mixes some of the better parts from klipsch, danley, and ess. If you've got the time, funds, and desire to tinker just go for it and let your ears tell you if it works or not.

[Tarheel TJ]

Deleted 

Edited February 13 by Tarheel TJ
Question had already been answered.

[hyde maintenance]

Have read through this thread with interest (although a lot of the technical info is beyond me).  I’ve always been curious about the Heils and their ability to go low(ish).

I’d like to know if anyone has had any experience with the Beyma TPL-150/H, and if so, how a ‘winged’ Heil compares?

For my application I’d be looking to cross around 1100-1200hz, hopefully starting with a single winged unit per side.

[Chris A]

I'm not sure that you're going to find someone with experience with both AMT drivers, especially with winged/stacked AMT-1s. 

 

I can say that the winged/stacked AMT-1s have a dipole airiness about them that is due to their "two-sided horn" construction.  If you are comparing to a Beyma TPL-150/H, you get a very nice sounding dipole effect out of the AMT-1s due to their controlled directivity in both front and rear directions relative to the Beyma AMT. 

 

The trough-type horn of the stock single-high AMT-1 is good down to ~1800 Hz, at which point it begins to lose horizontal directivity control.  Therefore its on-axis SPL begins to degrade and its harmonic distortion begins to show up at higher SPL (i.e., above 95-100 dB at 1 m).  Below 670 Hz, the stock AMT-1 loses both directivity control and the 1/4 wavelength starts to exceed the ribbon length, at which point the SPL takes a nosedive. 

 

If you provide the double stack AMT-1 and increase the length of the trough-type wings from the plastic case steel laminations, the low frequency cutoff depresses to about 570 Hz--or slightly lower.  The effective sensitivity of the double-stack AMT-1s also increases to about 98-100 dB at 1m on-axis.  This is low enough to use the AMT-1s on top of Belle and La Scala bass bins (i.e., horn loaded). 

 

So you've in effect got a fully horn-loaded loudspeaker without the attendant problems of a separate horn-loaded tweeter and K-55 midrange--including the time misalignment and non-flat acoustic phase and electrical impedance curves. If you bi-amp the AMT-1 with a Belle or La Scala bass bin and use a DSP crossover to provide EQ, you've got a killer deal.  This configuration is what I use for my current surround loudspeakers: Belle bass bins with AMT-1s on top.  They sound really good...good enough to be front loudspeakers in a conventional stereo setup.

 

I'll stop there...Does any of this begin to answer your questions?

 

Chris

[hyde maintenance]

Thank you for the response Chris. While it doesn't directly answer my questions, it does consolidate some good info.

 

A lot of people are pulling the rear cover off of their Beymas to make it a dipole, so a comparison with the a winged AMT-1 would be interesting. They seem to meet somewhere in the middle after their respective mods.

 

At any rate, I've decided to dip my toe in with a pair of AMT-1s and I'll see where it takes me.

 

Cheers

 

 

[Thaddeus Smith]

I received this email from ESS this afternoon and likely so did @Chris A, @Rudy81, @Pete H, and others. Hopefully this becomes a long term viable option for enthusiasts..

 

Quote

First off, we hope you're having a great Monday! 

 

You are our loyal clients, partners, vendors, and more, and we are so grateful for your relationship and support over the years. We have an important announcement for you, in that Rick Caudillo, CEO for over the last decade, is no longer with ESS. We wish Rick the best, and over here at our headquarters, will continue driving strong.

 

Right now, we're placing our main focus on creating transparency within our professional relationships, clients, and future clients. If you are waiting on backordered items, know that we are actively resolving that issue and are working hard to deliver it to you as soon as possible. If you are waiting for a response for a question, I ask you to please send it to us at (info@esslabsusa.com) and we'll get you assistance ASAP. We apologize for any delay, and greatly appreciate your patience. 

 

In the very near future, you can expect consistency, quicker communication, and even some new products! Speaking of quicker communication, our phone number will remain the same. However, for the quickest response, feel free to send us a message on Facebook, Instagram, by email or text at 206-747-6180. 

 

Thank you again, and we look forward to speaking to you soon. 

 

Take care, 

Shay De Castro 

 

ESS Laboratories LLC

(323) 496 8058

Toll-Free: 888.ESS.8720
Office: 626.443.8324
www.linktr.ee/esslabs

 

[Chris A]

Thanks Michael. 

 

I didn't receive the email that you did, above, so I was unaware of this communication. 

 

I just sent a new email to the company to remind them of my failed AMT-1 driver diaphragm from 29 January 2020, one driver out of the four AMT-1 drivers that I had bought for this purpose--that remains inoperable after its first few minutes of initial operation at 100 dBSPL (1 m on-axis). I was assured via telephone conversation with Rick Caudillo at that time that ESS would replace the failed diaphragm at their cost.

 

I haven't been able to complete my double-stack AMT (stereo) setup to report my own findings here because of this situation, and this project is currently unfinished, awaiting action from ESS to replace the diaphragm. 

 

"Hope springs eternal."

 

Chris

[Rudy81]

I did receive the email and I guess Rick has moved on.  It will be interesting to see what they  do with the company in the future.