The HOMster! (or How I Learned How to Fix a Horn)

[naru177]

Hello Mr. Bateman,

First off, I must Thank You for the very interesting and educational threads on HOM of horns! Through these threads I was introduced and intrigued by Dr. Geddes work--amazing stuff! One day I hope I will be fortunate enough to sample his system and have one in my home

In the meantime, I would like to build my home theater system using USD A-700 horns from my previous car--car was broken into and all my components besides the horns were stolen. Currently I have a Marantz sr6005 receiver on route and the horns and nothing else. My knowledge in audio is elementary at best and I am pretty much stuck. I was wondering if you could recommend a budget setup for this type of system (I plan to go stereo rather than surround sound). Here are some specific questions that I had:

1)Should I use a passive or active crossover?
2)Should the crossover be at the manufacturer's recommendation of 800zHz?
3)Midrange frequency coverage: Do you recommend pairing with some midrange drivers (I can't seem to find any one way midrange bookshelf speakers straight out of the box) or do you think pairing with a sub (or three per Dr. Geddes) would suffice?

I know your time is precious and so any help would be much appreciated!

Thank you in advance,

Fred

[Patrick Bateman]

I've received a few emails asking about where to buy the reticulated foam that I used in this project. I bought it from McMaster Carr. They stock a gazillion products, so I thought I'd post the part numbers on this thread, in case you guys could use that.

I am using 1/2" reticulated foam. It's part #2195K53 and it's $107 for a lifetime supply. (OK, that's forty square feet, but it's more than I'll ever need.)

I first used 1/4" foam, which is part #2195K52, but I wouldn't recommend that. It's a p.i.t.a. to work with due to requiring twice as many layers.

Geddes has noted that ideally you should use a solid block of the stuff. Pretty sure that would cost hundreds of dollars though.

If I'm not mistaken, plain ol' polyester fiberfill will function in a similar manner as the reticulated foam. The foam has a number of advantages though:

• The density is consistent, so you won't run into a situation where the stuffing on one side isn't consistent with the stuffing on the other
• the foam doesn't 'settle' due to gravity. I've had my Summas for four years now and the foam plug hasn't shrunk or settled or deformed whatsoever. The foam plug looks exactly the same as it did when i bought them.
• If you use fiberfill, you would have to weigh it on a scale to be sure that the amount is the same on both sides, and again, you can't get the density to match as well as you can with the foam.

The advantage of polyfill is that you can get it at Wal Mart, any craft store, it's 1/10th the cost, etc

[weltersys]

Originally Posted by Patrick Bateman

I've received a few emails asking about where to buy the reticulated foam that I used in this project. I bought it from McMaster Carr. They stock a gazillion products, so I thought I'd post the part numbers on this thread, in case you guys could use that.

I am using 1/2" reticulated foam. It's part #2195K53 and it's $107 for a lifetime supply. (OK, that's forty square feet, but it's more than I'll ever need.)

Geddes has noted that ideally you should use a solid block of the stuff. Pretty sure that would cost hundreds of dollars though.

If I'm not mistaken, plain ol' polyester fiberfill will function in a similar manner as the reticulated foam.

The advantage of polyfill is that you can get it at Wal Mart, any craft store, it's 1/10th the cost, etc

Polyfill absorbs high frequencies, the reticulated foam has much less HF attenuation.