[fcostantini]

Newbie here, just getting back into the hobby now that my basement is finished and I have a man-cave!

I saw Danny's videos for XLS builds, and he uses a few screws to mount the crossover inside the cabinet.  Would it be worthwhile to use some silicone adhesive dabs under the crossover board as well as the screws to help minimize potential vibrations?

Thanks,
Frank 

[mlundy57]

I super glue hard rubber washers from the plumbing repair section of a hardware store to the underside of the boards where the screw holes are. then the screws go through the board and washers.

[eichlerera1]

Washers or silicone will do little to damp box vibrations.
If you're serious, use external crossovers.....

[g3rain1]

Washers or silicone will do little to damp box vibrations.
If you're serious, use external crossovers.....

Is there any evidence to suggest caps inductors or resistors are microphonic? These aren't tubes were talking about.

[ric]

A few years back I replaced a few caps with some coke can sized caps (Jupiter). Needless to say the XOver did not fit back in the small space that it came from so an outboard Xover was necessary. At one point I was talking to the Herbie's Audio guy and he was saying sonically if you use a caulking type of adhesive to use blue RTV silicone which I did, to attach one cap to another. Eventually I tried using IsoAcoustics oreas under the glued together coke can sized Xover instead of it sitting on the ground (wood over concrete) and I DID hear a difference in sound quality. Not huge but enough so that if you can hear, say changes in speaker cables, you should be able to hear a difference.
   IMO all Xover's should be outboard and modular, which would allow changing out of Xover parts or the whole unit, as well as vibration isolation. YMMV!

[Peter J]

I've used a variety of things, but I don't look at it from a sonic standpoint so much as a mechanical one. If one uses thru-board tie wraps they tend to belly down on backside of crossover board and make for an uneven surface.

Recently I used this because I had some on hand after doing some deadening on truck. The butyl should damp the panel some, the foam should accommodate the tie wraps and lend more even support when screwed down. I like it enough to add it to my arsenal.

https://www.parts-express.com/Sonic-Barrier-MX-4-Max-Aluminum-Foil-Butyl-Foam-Rubber-Sound-Damping-Sheets-31.5-x-18.12-4-268-046

I doubt there's need for concern from vibration or microphonics standpoint.

[eichlerera1]

I use the Hales Signature System Two Speaker featuring external crossovers.

From Robert Harley's review:
Mounting the crossover externally is an unusual design. The only other speaker with an external crossover that comes to mind is the Avalon Ascent. The rationale behind this expensive feature is isolating the crossover components from the mechanical vibration present inside the loudspeaker enclosure. According to Paul Hales, such vibration can induce voltages, albeit tiny ones, in crossover components and thus introduce distortion in the input signal. Filling the crossover with sand and mounting it on spikes further isolates crossover electronics from vibration

[Vince in TX]

I didn't bother with screws on my A/V-1RS speakers because there was no room to get a screwdriver in there.   This industrial Velcro works great!

[Neo]

I've used a variety of things, but I don't look at it from a sonic standpoint so much as a mechanical one. If one uses thru-board tie wraps they tend to belly down on backside of crossover board and make for an uneven surface.

Recently I used this because I had some on hand after doing some deadening on truck. The butyl should damp the panel some, the foam should accommodate the tie wraps and lend more even support when screwed down. I like it enough to add it to my arsenal.

https://www.parts-express.com/Sonic-Barrier-MX-4-Max-Aluminum-Foil-Butyl-Foam-Rubber-Sound-Damping-Sheets-31.5-x-18.12-4-268-046

I doubt there's need for concern from vibration or microphonics standpoint.

Does the aluminum layer in this or other Automotive sound dampening materials have any adverse effects on sound, reflecting sound or vibration?
I have used this material before (not in speaker) and had thought about it for my speaker build but had these concerns.

[Peter J]

Does the aluminum layer in this or other Automotive sound dampening materials have any adverse effects on sound, reflecting sound or vibration?
I have used this material before (not in speaker) and had thought about it for my speaker build but had these concerns.

No effect that I can imagine. If I were to guess, I'd say you're thinking along the lines of the thermal properties of thin reflective films. While it might seem like a parallel analogy, it's simply not. Imagine covering the inside of a speaker box with aluminum foil. Nothing going on inside that box knows or is affected by the reflective properties of the foil, although I can hear the potential marketing hyperbole as I type 

In the case of this product specifically, I'd guess the foil is there to aid in conformability and lending strength to the butyl.  I'd have no concern of deleterious effects used in the way described. I should note that it won't replace the box stuffing effect of the much thicker foam on NoRez.

[iteachsteam]

If you are going for convenience and less clutter, mount them inside.  I use what other's have mentioned about rubber washers and silicone dabs here and there, but those are mostly just more to make you feel better about it... the parts are going to vibrate no matter what.  I prefer external amps/crossovers if possible.

[Hobbsmeerkat]

I recently upgraded a pair of Spica TC-60s for a customer (video from Danny coming soon, tho the actual upgrade was done after the recording)

I used a combination of good quality 3M adhesive strips on the bottom of the crossover board, and a single wood screw in the middle to secure the new crossover into place. Get some isolation from the foam strips, and a strong achoring from the screw.

I would have used a couple more screws holes, but the space inside was too tight to add much else. There was no flex/wobble from the board however.

Tbh any combination of screws, glue, adhesive strips etc, should hold up just fine, but fhe more secure the attachment, the better.