I got into audio my freshman year of collage in 1973. While I hated the "West coast sound",
The JBL L100 looked great, and had a great woofer. It is also higher efficiency than most.
HTGuide did a Thread on redesigning the XO and made a very appealing speaker.
I looked up the woofer and its 88 db efficient. So much for perception of efficiency.

My thought was to design a 3 way speaker that is ultra low distortion, 50Hz F6, and 93db efficiency. Borrowing the L100 concept, Driver compliment 12" woofer, 4" mid-range and OS compression driver.

There are at least 3 drivers in the 4" class with 93db Audax HM100Z0 4" Aerogel Mid-range ,
Fostex FE126En 4" Full Range
I already have and love MP14RCY/P in ob, but they are only 90db sensitivity.

The B&C 3/4" or 1/2" CD look like they might be a perfect match. Sure beats a 2" paper tweeter.
Even a B&C...

Nelson has created a storm of interest with the Zen I/V.

I have a DAC that I can use this with, a K&K RAKK DAC Mk1.

Currently, it has a passive supply and a switchable shunt resistor.

So I am brainstorming on what it would take for an active Zen I/V with a shunt volume control, and both SE and Balanced outputs.

Basics: PCM1794 has differential outputs with 8 ma current output.
https://focus.ti.com/lit/ds/symlink/pcm1794.pdf
So I need 2 Zen I/V per channel.
At present, I am running a DCX2496 Digital crossover, so balanced outputs are a plus.

I am considering using the buffer from this post.
Since bipolar supplies are required for the I/V section, a buffer that does not require additional caps seems prudent.

For the volume control, either https://www.kandkaudio.com/linestage.html Shunt Stepped attenuator or a single LDR replacing the K&K unit.

Finally,...

Here is my brothers response to the first version of the Shunt Regulator wiki. I actually wrote it for him so he could get a clue of what I was babbling about.

Дуг,

Это бумажное средство приблизительно столько же, сколько эта электронная почта будет означать для Вас. Я думаю, что это хорошо написано. Вы будете нуждаться в этой связи, чтобы выяснить то, что пятку я только что написал Вам, поскольку это находится на русском языке.

http: // translation2.paralink.com/

Кит

Here is a translation:
Arcs, This paper means approximately so many, this how much electronic mail will indicate for you. I think that this is well written. You will require in this connection in order to explain that the fact that I recently wrote heel to you, since this is found on the Russian language.

For thoes of you that are curious, the article is here:
https://www.diyaudio.com/wiki/Shunt_Regulation

This is my foray into the dark side.
The only horn speakers I have ever heard was a K horn being driven with a Phase Linear 700.
Could not stay in the room.
Now I am curious if it can be better.

I have a 3 DCX2496 and 6 channels of amplification, so I will start with an active system.

My goal is to get the drivers close to 100db or higher efficiency.
I want to be able to experiment with low power amps.
I am also frugal, so I want to use low cost waveguide components.

Compression tweeter
Direct radiation mid
Woofer/Woofers.

JBL 2123 is my starting point Second hand only.

B&C 6MD38 99db $89
B&C 8PE21 98 db $100
B&C 10MD26 100 db $160
B&C 10HPL64 98 db $130

Here is an example speaker.
https://www.diyaudio.com/forums/multi...ml#post1653499

I will start a thread after...

I have had my RAKK DAC going for a while now. Great DAC. I bought a case and the RAKK DAC passive board to replace the EDCOR transformers I was using and I am using the Shunt volume control to select the shunt resistor.

Goal is to get it done this week.
I will post pictures after its complete.