If you love big electrostatic panels, but have a small acoustic space-a speaker for you!

There are different versions and materials of the diaphragm for the larger Heil.

The early 1,1a,1b,1c, Monitor, 6 has a brighter sound and more brittle material too. Listening to both versions, yes they do sound different.  The later diaphragm and replacement version performs and sounds a bit softer as well.  With some help from a friend with access to anechoic chamber, testing was performed for my crossovers at 1.2k, 1.5k, and 2k and 1.2k was ideal in my setup. The originals were crossed over at 800hz and 1000hz later on as I recall from old tests.  Some keep spare diaphragms around for that reason. Perfect flat line graphs may not always sound musical, and the heil air motion tweeter is one of those cases for debate for sure. Let your ears be the judge :)     


 

Here are some frequency response curves taken in my listening room 1 meter back from the speakers. We found with extensive testing that the Great Heil does not like to be crossed over < 2 Khz as it sacrifices power handling and thins out the midrange. The original AMT 1's from the 70's that I heard in Germany when stationed there sounded bright and boomy to me so we tested in the 2 Khz range and found that the midrange filled in nicely and it sounded far smoother..

https://www.shinjitsuaudio.com/graphs

Terry, I bought my ulfers after reading your review on those also. I have no idea what space I will use these ones for yet. Maybe a bedroom area 14x12 or so. 

Nice. Great to see it!

40 years building with the Great Heil AMT. I worked at ESS building them on the assembly line. Built several custom versions since.

Prefer crossing over at 1,200hz vs 2k to retain Heil midrange magic.

Listening to my custom DEC-AMT28 speakers right now with QS Mono 120 Tube amps. :) And, former low watt triode and strapped triode tube amps too. May retest other lower-watt MOSFET SS amps again with Great Heil. 

FYI, other custom AMT builds by members on AudioKarma, here:
https://audiokarma.org/forums/index.php?threads/custom-built-ess-amt-heil-based-speaker-thread.57722...

Cool :-) I have a bit of experience with the AMT, it can sound very nice !!! Good on you for creating something new !

Hello!

Thanks for the cool reference. The name means "Truth Audio". I wanted to build a speaker brand that reproduced the transient attack and speed of the original music while keeping costs reasonably affordable.

It may seem a bit odd to marry a 4 inch driver with a Heil AMT but the speed and light weight of the Fostex driver at under 4 Grams matches the diaphragm speed of the Heil. They hand off to each other at 2 K which maximizes dispersion and widens the listening window. Full range drivers in general tend to beam as the frequency advances beyond say 2 Khz.

@shinjitsuaudio congrats!!! What is the origin of the firm name ? My Sensei used a variant of that as firm name as well...

Hey speedbump6,

Congrats! I think you are in for a treat. How big is your acoustic space and what is your upstream gear?

review pair review is no longer avaible, lol. Looking forward to listening to them. 

Hey snapsc,

These speakers were placed in my upstairs system, if you go to Six Moons website and look in the archives for my review on the Perfect Set speakers there is a picture of the space, which is a type of second floor balcony with no back wall or side wall. The system is setup for near field listening. Yet, the Daisho speaker did very well with both the mid bass and excellent taut and extended bass. I would attribute this to the tuning of its back loaded 5.5 ft. horn loading. If you read my review for the details of what this speaker has to offer and you are intrigued, you might want to take the risk of the 30 day trail period. Also these are small speakers, so you don't have to break your back to audition them. I'll still stick to what I said in my review, you need to get them up at least six inches off the ground to get them to 'sing" regarding their ability to sound-stage and image like a big panel speaker. 

Terry... you have a pretty big listening room.  What can you say about how the low end and mid bass sounded from a small (4”) driver?

I have gotten a lot of Emails that are asking very technical questions about the back horn loading. I would suggest you contact Morris who is the designer/builder and will be able to answer these questions much more skillfully then me.

Thank you Teajay for the review. I have listed the review pair for sale at a reduced price.
We are in the final build of a new model: "Shinjitsu Audio Diasho Blade". This two way speaker is driven from 60 Hz to 2 Khz with the exquisite Markaudio Alpair-7P Paper Cone 4" Full Range in a cabinet composed of HDF and Wasp patterned aluminized fiberglass. 2 Khz to 20 Khz is driven by an authentic full size Heil AMT transformer made in the USA by ESS. The pale blue driver complements the silver front and back side beautifully. Side panels are carbon fiber black.