Blackhole 5

PaulDF · 09-18-2003, 12:12 AM

I plan to order my A/V 3 kit in the next few days and have a few more questions I'd like everybody's opinions on... Rather then drudge up the longish thread I started a few weeks ago, I thought I'd start a new thread to keep things simple and quick.

I've decided to definitely get the sonicap upgrade, but am undecided about Blackhole 5. I have read all I can find on this site and others about BH5, and have seen mixed rewiews. Most of the posts I've found are at least 6 months old, so I thought there might be more opinions about it by now.

Since I live in Canada, the final cost, as far as I can figure, for the two required sheets of BH5 will be about $180.00 after shipping. That is a lot of money for something that my untrained ears might not even notice. A lot of people will say to use other products, which may be effective to some degree, but I doubt any will provide as much improvement as BH5. Since I am a beginner at most of this, I don't want to cut any corners or try to improvise. I don't want to have any doubt when all is built and done. I plan to keep these speakers for many years.

I do not doubt Danny or his opinion of the BH5, as he recommends I use it.

The improvement the A/V 3s will be over my current speakers is going to be tremendous. With such a huge upgrade, is it really necessary to take those few extra steps further? I seem to be talking myself into it as I type...

All opinions appreciated! Thanks.

Pete Mazz · 09-18-2003, 07:37 AM

You could substitute BH5 with felt. Make sure the felt has a high wool content and use 1/2" or more.

Pete

Hank Frankenberg · 09-18-2003, 08:06 AM

I called an acoustical engineering company the other day and had an interesting discussion. The company analyzes sound control situations, from speakers to industrial applications. The bottom line of their advice was that BH5, like some other audiophile products, is a very expensive product that has features that don't really help (mainly, the barrier layers. The engineer said a layer of foam is hard to beat. Regarding felt, as Pete notes, I understand that it must be thick and real wool. Personally, I use the vinyl dampening sheet material from P.E.
That's all I know and will shut up now. This subject is dangerously close to interconnect and power conditioner discussions.

Brian Bunge · 09-18-2003, 10:23 AM

Danny recommends using 1" thick foam if you don't go with the BH5. As a matter of fact, on the pair of cabinets that we built for him he told me just to glue in some 1" foam.

I do like the added rigidity the BH5 adds to A/V-1's and A/V-2's, but with all the bracing in the A/V-3's I don't see it as being as much of an issue. The cabinets are already around 50lbs. each without the drivers and XO's installed.

MikeSRC · 09-18-2003, 12:25 PM

I've just started on a pair of A/V-3s (and A/V-3S center channel). Like Paul, I got the Sonicaps but not the Blackhole to save a few bucks. Danny told me that I should use a fiberfil material behind the drivers and foam on the front and back walls of the transmission line. I was planning on going with the PE 1-1/2" convoluted foam.

This forum is an incredible resource and I'd be lost on this project without it (I may still be lost, but at least I've been told the right way to do things

).

Thanks to all.

**HTF Ads**

Chris Tsutsui · 09-18-2003, 01:55 PM

Hank, I'm wondering why you would use the PE Vinyl damping sheets in a speaker cabinet? Isn't that unrelated to the effects that fiberfil, wool, and blackhole5 would have on the internal resonances?

It would be like putting dynamat on the enclosure to prevent actual resonance of the wood itself changing the cabinet resonance if the cabinet isn't braced well.

IMO, adding some sort of foam, polyester, wool, etc really does add to the detail in bass and often the frequency response of the speaker. I just wouldn't go as far as to pay $180 for blackhole 5, but would settle fine for something that costs a fraction of that.

BTW, good luck with your AV3s Mike.

AllanRW · 09-18-2003, 02:22 PM

You want something to try for econ best results.
Go buy a few cheap clearance peal and stick floor tiles.
Cost $1.00 each at the most.
Line the back wall top and bottom of the cabinet with this.
Line the cabinet with 1" foam bed pad purchased for around $10.00 CND at a dollar store.
Glue the pad onto the peel and stick tiles.
The tiles the thicker the better.As you are trying to stop the cabinet vibration with this or the BH5 layer it uses.

Ultra cheap with results that are worth the time.

Good luck.
As well just to let you know Bob at CSS has some BH5

Al

MikeSRC · 09-18-2003, 03:35 PM

Quote:

BTW, good luck with your AV3s Mike.

Thanks Chris. I apologize for not geting back to you, but my father-in-law has offered to help me with the cabinets. He's an amateur woodworker and has the tools I don't. So somehow, we'll muddle through.

BTW Chris, have you ever purchased any veneer from these guys: www.arborveneers.com? They're not that far away so I could actually look at the stuff before I buy it.

PaulDF · 09-18-2003, 11:48 PM

Well I looked for felt today with a high wool content, with no luck. Got some stupid looks from the ladies though. I have been back and forth today on the BH5, but now the foam suggestion is looking pretty good to me. Just ordinary 1" foam?? How dense does the foam need to be?

Brian, did you use the foam behind the drivers too? Or something else? And did you line the sides as well as the front and back walls?

I can see how the peel and stick tiles might work for resonance, but I'd be afraid they'd fall off inside the cabinet! The A/V 3s do look to be quite extensively braced, so maybe all I need is foam...

Brian Bunge · 09-19-2003, 12:18 AM

Paul,

I only installed the foam on the front/back walls below the woofers. Danny handled the rest after we shipped the cabinets to him.

ThomasW · 09-19-2003, 12:23 AM

Paul

You are confusing a couple of things.

Mass damping, adding weight to the cabinet via an adhesive metal foils, elastomeric membranes or other means to increase the weight of the cabinet therefore lowering the cab Fs.

absorbent/friction damping, these are materials such as felt/foam/fiberglass/etc. They are used to control/absorb the rear wave coming off the drivers.

Products like BH5 offer small amounts of mass damping and some absorbent damping. But IMO they are too pricey for the benefit they provide.

The best cabs have adequate mass damping simply from proper construction. They then can be fine tuned with absorbent damping materials.

You can find high wool content felt from custom gasket makers/materials in the yellow pages or it can be ordered from McmasterCarr.com