Small oak loudspeakers

[Helvetica]

Solid wood isn't really the right thing to use for a speaker enclosure, as it'll move (and therefore affect the box seal). However, for such a small item I decided I could wing it.

I wonder would a thick (10mm) veneer glued to MDF bring stability to the solid wood? I don't like bought glued veneer they never look real to me.

 

[sploo]

Solid wood isn't really the right thing to use for a speaker enclosure, as it'll move (and therefore affect the box seal). However, for such a small item I decided I could wing it.

I wonder would a thick (10mm) veneer glued to MDF bring stability to the solid wood? I don't like bought glued veneer they never look real to me.

Unless you had a specific need for 10mm thickness then I wouldn't advise that (i.e. buy 1-1.5mm thick real wood veneer or cut your own [likely a bit thicker] on a bandsaw).

With 10mm of real wood on (assuming no more than 12mm) MDF I wonder if movement in the wood might cause the panel to bend. A 1-3mm wood veneer should be pretty stable though.

The only problem with veneering is edges - i.e. getting curved edges on the front of a speaker. Hence it's common to have a veneered box with a front baffle that's painted black (the front edges of the baffle being rounded over).

 

[Helvetica]

I'm thinking of recreating something like these boenicke speakers, I'm sure it's veneer but beautifully finished and such an unusual design

 

[sploo]

I'm thinking of recreating something like these boenicke speakers, I'm sure it's veneer but beautifully finished and such an unusual design

I would suspect so, yes.

My concern would be the sharp edges on the front baffle - a significant cause of diffraction; though you do need unrealistically large roundovers to really push diffraction away from important frequencies. That said, the evidence for diffraction being an audible problem is sketchy, so maybe it's not such a big deal.

 

[Beau]

Interestingly chipboard is the best for acoustics. I made speakers years back and cut some constructional veneer and laid it on 25mm mdf (couldn't bring myself to use chipboard)

Lovely looking speakers Sploo. Are they Jordan Watts cones? Probably not but they were well regarded back in the day.

 

[sploo]

Interestingly chipboard is the best for acoustics. I made speakers years back and cut some constructional veneer and laid it on 25mm mdf (couldn't bring myself to use chipboard)

Lovely looking speakers Sploo. Are they Jordan Watts cones? Probably not but they were well regarded back in the day.

I'd be very wary of chipboard for speakers - way too much risk of crumbling and bits rattling around. There's argument over MDF (and HDF) vs plywood, but I'd generally go for MDF as it's homogeneous, dense, and relatively cheap.

The drivers are from HiVi - see the link to the Zaph Audio site in the opening post. Very good for the money.

 

[Beau]

Interestingly chipboard is the best for acoustics. I made speakers years back and cut some constructional veneer and laid it on 25mm mdf (couldn't bring myself to use chipboard)

Lovely looking speakers Sploo. Are they Jordan Watts cones? Probably not but they were well regarded back in the day.

I'd be very wary of chipboard for speakers - way too much risk of crumbling and bits rattling around. There's argument over MDF (and HDF) vs plywood, but I'd generally go for MDF as it's homogeneous, dense, and relatively cheap.

The drivers are from HiVi - see the link to the Zaph Audio site in the opening post. Very good for the money.

I know the chipboard thing sounds strange but that came from a Peter Comeau who is now director of acoustic design at International Audio Group. He used to live nearby and enthused about how chipboard was perfect for speaker cabs but sure they were fussy about the quality. This was when he designing Heybrook speakers.

 

[sploo]

I know the chipboard thing sounds strange but that came from a Peter Comeau who is now director of acoustic design at International Audio Group. He used to live nearby and enthused about how chipboard was perfect for speaker cabs but sure they were fussy about the quality. This was when he designing Heybrook speakers.

I suppose it's dense, and should be reasonably homogeneous. It's just that any I've encountered has been prone to crumble; it's also not known as the hotdog of the wood world for nothing. I can't think why it'd be preferred over MDF. Really all you need is something that isn't going to vibrate and add colouring to what the drivers are producing. Heck, concrete would be ideal, though not very practical (but it has been done)!

 

[Beau]

He demonstrated in a very low tech way by taping on a panel. MDF had a bit of a ring but the chipboard they used was very dead. He did explain but it was many years ago and I don't have the best memory but I think it was along the lines of different densities you get in chipboard with the core being less dense to the outer face. I also think it partly due to it being lighter as a lighter cabinet has less momentum (apparently) I must add I am talking about things way above my pay grade . In later years think they ended up using MDF as from the visual design point of view it was far superior in that they could stain up moulding and edges to match veneers. Peter was very grumpy about this as for him sound was everything and did not like compromise in this department. Thing is everything vibrates. I think the perfect speaker should be very light yet have no resonance obviously unachievable so compromise has to be made. MDF definitely has some resonance. I used it for a Peerles kit and a Dynadio one and neither was immune to singing along.

 

[sploo]

He demonstrated in a very low tech way by taping on a panel. MDF had a bit of a ring but the chipboard they used was very dead. He did explain but it was many years ago and I don't have the best memory but I think it was along the lines of different densities you get in chipboard with the core being less dense to the outer face. I also think it partly due to it being lighter as a lighter cabinet has less momentum (apparently) I must add I am talking about things way above my pay grade . In later years think they ended up using MDF as from the visual design point of view it was far superior in that they could stain up moulding and edges to match veneers. Peter was very grumpy about this as for him sound was everything and did not like compromise in this department. Thing is everything vibrates. I think the perfect speaker should be very light yet have no resonance obviously unachievable so compromise has to be made. MDF definitely has some resonance. I used it for a Peerles kit and a Dynadio one and neither was immune to singing along.

Yea, the different densities thing can be useful - but generally it's preferable to do it in a controlled way (i.e. limp mass membrane), rather than relying on the... err... "vagaries" of hotdog wood

Though to be honest I'll usually just brace a larger box; such that you push the resonant frequencies up into ranges where there's less energy (i.e. less energy to make the panels vibrate).

 

[Racers]

I painted the insides of my KEF coda 3's car body underseal, they sounded much better afterwards, but smelt for a long time, I solved that by selling them!

Pete

 

[Harbo]

I use a pair of Heybrooks - really nice speakers.

Rod

 

[sploo]

I painted the insides of my KEF coda 3's car body underseal, they sounded much better afterwards, but smelt for a long time, I solved that by selling them!

Pete

Yea, I understand that's partly a limp mass type solution (as well as controlling internal reflections). The use of cheap carpet tile (dense limp mass membrane plus fluffy fibres to control vibrations, and a fairly wide band internal frequency absorption) helps too.

A driver consists (intentionally) of thin material, through which internal box reflections can radiate; thus when you get an impulse from a driver, the rear wave bounces off the back of the cabinet, then re-radiates through the driver cone (at some point in the near future). Controlling internal reflections through absorption (or angling the rear wall so it's not parallel to the driver) can be beneficial.

 

[Racers]

I did put the foam back in as well, I replaced them with Quad ESL57's which got replaced with Shahinian Arcs!

Pete