Switch to full style
A place to discuss member's DIY audio projects & post pictures/schematics. NOTE: There is a limit of 2MB per attachment, and a maximum of 3 attachments per message. If you need to post more than 3 attachments, just add another message.
Post a reply

Joseph Crowe - Sabourin Horn Speaker

November 3rd, 2022, 2:24 pm

Pursuant to Jim's suggestion, I figured I share a horn speaker I built for my brother at the end of last year (but just finalized crossover work a month or so back). The final crossovers have yet to be built.

The horn was designed by Joseph Crowe. The planner driver used is the GRS PT6825-8

I decided to go with my own woofer choice (Dayton Audio - DSA-315-8) and my own crossover.

The final picture shows them on the inside of the other speakers in the room. After Jim came and auditioned the speakers, he suggested I move them further apart (now they are on the outside). This resulted in a HUGE improvement in soundstage/presentation. Almost night and day.

For those interested, some pictures below:

Image

Image

Image

Image

Image

Image

Image

Image

Image

Image

Image

Image

Image
Last edited by dkalsi on November 3rd, 2022, 3:40 pm, edited 1 time in total.

Re: Horn Speaker Build

November 3rd, 2022, 2:50 pm

Someone really likes Baltic Birch plywood. What is the horn driver?

Re: Horn Speaker Build

November 3rd, 2022, 3:25 pm

FINALLY! Someone is using acoustic fill other than that damn reactive polydacron. :thumbup:

Re: Horn Speaker Build

November 3rd, 2022, 3:41 pm

brombo wrote:Someone really likes Baltic Birch plywood. What is the horn driver?


Hahah - my woodshop is in my basement, so no MDF is allowed in the house.

The horn driver is the GRS PT6825-8

Re: Joseph Crowe - Sabourin Horn Speaker

November 3rd, 2022, 4:10 pm

Are you putting a back volume on the horn driver to balance the horn impedance? What is the crossover frequency?

Re: Joseph Crowe - Sabourin Horn Speaker

November 3rd, 2022, 5:34 pm

I believe the rear chamber is approximately 7 liters and fully stuffed. The crossover frequency is about 500hz.

Re: Joseph Crowe - Sabourin Horn Speaker

November 3rd, 2022, 5:42 pm

Very nice! Did you think about laying up the horn with fiberglass cloth on a form for a smooth curve?

Re: Joseph Crowe - Sabourin Horn Speaker

November 4th, 2022, 9:50 am

Regardless of how this sounds, you clearly have incredible wood working skills. Impressive!

Re: Joseph Crowe - Sabourin Horn Speaker

November 4th, 2022, 10:09 am

Super impressive mitering. I assume you use CAD to figure out all the angles and resultant layout. What is not apparent (and equally important) are the jigs needed to both cut the wood accurately AND hold the pieces in alignment and clamped during glue-up. Everything can fit together dry just fine, but once you put glue on the joint, and start applying clamping pressure, it moves all over the place. This takes as much planning as the cuts. This is masterful work!!!

David

Re: Joseph Crowe - Sabourin Horn Speaker

November 4th, 2022, 10:52 am

Thanks Dave/David,

One can purchase the plans directly from Crowe's website - and it has all the details one would need to cut the individual pieces. What's awesome is now he has plans available for 18mm plywood. He previously only had plans for 24mm, and I had to recalculate dimensions myself to figure out how I would build with 18mm.

All pieces were cut on the miter-saw. Believe it or not, the woodworking part wasn't difficult, but understanding how each piece needs to be positioned on the miter saw was certainly a challenge.

Gluing the three petals of the horn flare also wasn't difficult (just used tape + wood glue), but gluing all four completed petals together was very challenging (jigs needed to be made, and I also used construction adhesive + brad nails). The construction adhesive allowed for a longer set time and has gap-filling properties.
Post a reply