Visit to Audiophile Bill to hear his horns project

[Walnut Horns]

Which ones are yours?

The horns on the metal stands.

 

[Zeotrope]

Wow

The horns on the metal stands.

those are stunning.

His pricing is funny, because he quoted me a “special price” using my own drivers for $150K, and his System Large was well over $300K a few years ago.

 

[Walnut Horns]

Wow

those are stunning.

His pricing is funny, because he quoted me a “special price” using my own drivers for $150K, and his System Large was well over $300K a few years ago.

Thank you.

I do not know Jeffrey's current pricing, but I was his first customer for the horns, which I've had for some time.

 

[Zeotrope]

That’s great! I bought the RCA 1443 from him.

 

[Zeotrope]

Crossover 101, you don't want the fields interacting of inductors. In order to avoid this you don't have their fields congruent with each other. I'd rotate the small so it's standing up so the field will be perpendicular, and not counter or additive to the same motion.

Your comment reminded me that I need to redo the crossovers, thank you. I finally found a local expert to voice the speakers in my room, measure the response, and go through the tedious trial and error to design an optimal passive crossover.

The difference is staggering! The 3 drivers are now within 5dB from 40Hz to 13,000Hz. Of course, the Fostex tweeters go a lot higher, but they drop off further about 13k. And keep in mind this is in my far less than optimal very small room.

For anyone interested, the RCA1443 with the conical midrange has zero hint of the “typical” horn sound.

Funny story: the crossover engineer hasn‘t worked with a lot of horns in his 4-decade career. At first, I could tell he thought the speakers would not be great, just by looking at them. After 2 days, and still not with the optimal crossover, he didn’t want to leave! He exclaimed: “These sound better than $100k Wilsons!”.
Yup, that’s the idea

 

[Zeotrope]

Bill, or anyone, any suggestions for 2 subs that will mate well with the horns?
The transmission line sub with a 500W 10” driver is not cutting it, according to my crossover engineer.
Keep in mind that my room is only about 150 sq ft, and open on one side… so I don’t need a ton of power.
I’d rather have fast, tight, clean lows between 30-80Hz vs the ultimate extension for movies.

 

[cal3713]

Bill, or anyone, any suggestions for 2 subs that will mate well with the horns?
The transmission line sub with a 500W 10” driver is not cutting it, according to my crossover engineer.
Keep in mind that my room is only about 150 sq ft, and open on one side… so I don’t need a ton of power.
I’d rather have fast, tight, clean lows between 30-80Hz vs the ultimate extension for movies.

I'm a believer in Duke's Audio Kenesis Swarm... you'll end up with 4 subs, but they're not huge room dominating things. I haven't personally tried mating them with horns, but Duke sure has.

 

[Audiophile Bill]

Bill, or anyone, any suggestions for 2 subs that will mate well with the horns?
The transmission line sub with a 500W 10” driver is not cutting it, according to my crossover engineer.
Keep in mind that my room is only about 150 sq ft, and open on one side… so I don’t need a ton of power.
I’d rather have fast, tight, clean lows between 30-80Hz vs the ultimate extension for movies.

Hi Surge,

Have you tried to build any of the tapped horn subs at all? Might be worth exploring with say a lab 12 or one of the various 15” pro woofers. Quite a few plans available online.

Another more tuneful option would be a Bill Fitzmaurice sub (such as Tuba) depending on space.

Something like Leif’s front loaded horn towers would obviously be too big.

 

[christensenleif@msn.com]

my son has a TUBA HT with 15 Dayton and it really kicks ass from 25-250........my first contender after the Skramstad sub towers

 

[Folsom]

I might ask Duke about making a set with some slightly different drivers if low end extension isn’t the goal.

 

[Zeotrope]

I might ask Duke about making a set with some slightly different drivers if low end extension isn’t the goal.

I’m looking at Duke’s now. Very interesting! And the form factor and price point is quite good…
I will ask him. Thank you!

 

[Solypsa]

Bill, or anyone, any suggestions for 2 subs that will mate well with the horns?
The transmission line sub with a 500W 10” driver is not cutting it, according to my crossover engineer.

Can you elaborate more on 'not cutting it'?

 

[dcathro]

And the field coil monsters have landed. Beautifully engineered and built. I can’t believe the density of each of the motors. I will be building and internal shelf within the horn chamber in order to prevent any possible shearing forces against the frame!

View attachment 80078

View attachment 80079

View attachment 80080

I have ordered 2 variable linear power supplies to get me up and running. Should arrive tomorrow with any luck.

Hey Bill,

Just curious as to your progress with these.

Cheers

David

 

[Audiophile Bill]

Hey Bill,

Just curious as to your progress with these.

Cheers

David

Hi David,

Hope you are well. I have been super busy at work so not had the chance still to implement the necessary internal rear chamber support work to install the beautiful field coil motors. Hoping to achieve this over the holidays - all being well.
I have been building a 2nd pair - the bass units are in Iroko. This was quite tricky since it is a very hard wood indeed.
My only other ventures in recent months have been modifying my Studer 812 to MTSL status, collecting more tapes, and working on the horn finish.

Here is a shot taken this week. The finish is 100% natural oil / wax.

 

[the sound of Tao]

Hi David,

Hope you are well. I have been super busy at work so not had the chance still to implement the necessary internal rear chamber support work to install the beautiful field coil motors. Hoping to achieve this over the holidays - all being well.
I have been building a 2nd pair - the bass units are in Iroko. This was quite tricky since it is a very hard wood indeed.
My only other ventures in recent months have been modifying my Studer 812 to MTSL status, collecting more tapes, and working on the horn finish.

Here is a shot taken this week. The finish is 100% natural oil / wax.
View attachment 84996

Beautiful work Bill… very inspiring. Thanks for sharing.

 

[spiritofmusic]

That's one handsome spkr.

 

[adyc]

Any impression on field coil with your speake?

 

[Audiophile Bill]

Any impression on field coil with your speake?

Hi,

Not tested it yet unfortunately. Hoping to achieve this in December. The reason it isn’t plug and play is the following:

> The field coil motors are so massive and heavy, it isn’t recommended or safe to free hang them against the speaker frame lest you bend it through the shearing forces. Thus to operationalise this I need to build a dedicated internal “platform” within the rear chamber that takes the weight of the motor whilst directly coupling the frame to the horn throat. It is very doable but will take me some time to plan and construct it.

 

[cal3713]

Hi David,

Hope you are well. I have been super busy at work so not had the chance still to implement the necessary internal rear chamber support work to install the beautiful field coil motors. Hoping to achieve this over the holidays - all being well.
I have been building a 2nd pair - the bass units are in Iroko. This was quite tricky since it is a very hard wood indeed.
My only other ventures in recent months have been modifying my Studer 812 to MTSL status, collecting more tapes, and working on the horn finish.

Here is a shot taken this week. The finish is 100% natural oil / wax.
View attachment 84996

Time well spent, they look amazing.

 

[Zeotrope]

Great job!
You are using Supravox field coil woofers as well, correct?
I can’t believe the sound now that I have a proper crossover!