How to make a loudspeaker

[Eric The Viking]

Natural wood is acoustically inferior to many man made boards, and it's also inconsistent.

The speakers I'd like to refurb are mostly birch ply, with deadening panels inside. I have others made from MDF and chipboard, albeit with veneer, and I think the venerable pair of 3/5As that I have are also ply.

 

[Racers]

There are two schools of thought light with low mass so lower resonances or heavy and stiff so lower resonances.

Early LS3/5a where 12mm ply.

Most of the Shahinians are birch ply apart from the old model Arcs.

Pete

 

[NazNomad]

I wonder how many people (without the use of very sensitive instrumentation) could tell the audible difference between a plywood, MDF, Padauk, Walnut, etc.. speaker cabinet.

I'll stick my neck out and say, absolutely none.

 

[Harbo]

I made some Lowther Acoustas (folded horns) some time ago from ply but never finished them - they sounded superb but are rather too large.

Rod

 

[xy mosian]

Time was when some speakers had hollow cabinet pieces which were filled with sand!
xy

 

[nev]

I wonder how many people (without the use of very sensitive instrumentation) could tell the audible difference between a plywood, MDF, Padauk, Walnut, etc.. speaker cabinet.

I'll stick my neck out and say, absolutely none.

If your saying how many people could identify what its made of I'd agree. If you're saying theres no audible difference between the same driver in the same size box each of a different material, wood, mdf, plywood etc then i think theres still room for you on the flat earth bus that Jacobs driving and you've been working with loud machinery too long.

Just to clarify - different, not better!

 

[Eric The Viking]

I've some old Monitor Audio MA7s. I had to change the bass drivers recently. Whilst I was doing that, I put a small roundover on the rim of the port, which changed the tuning slightly (probably no more than 5mm radius, max.). It transformed the sound, from having a nasty honk to being a smooth transition in the crossover region. You'd have to look hard to see the physical difference though. It's often surprising what you can hear (with normal hearing - mine is going off now). LS35A/s have a felt rim round the tweeter, in order to stop a resonance at quite high frequency, because it can be heard. Some of this stuff is snake oil, but not all of it by a long chalk.

Pete mentions two schools of design above - rigid enclosure and allowing the cab itself to radiate. My understanding is that the latter only became possible when there was cheap enough computing power to allow good analysis, and it goes with using moulded plastics (mainly) as cabinet material and active crossovers to equalise out what was hard to design-out physically.

JBL probably started the emitting-enclosure trend with their Control 5 series, along with EV with their S200 PA speakers, both remarkably good for what they were (for the time). IIRC, equalizers were available for both S200s and Control 5s.

But please nobody mention Bose: I'm eating my lunch... ;-)

E.

 

[bugbear]

Pete mentions two schools of design above - rigid enclosure and allowing the cab itself to radiate. My understanding is that the latter only became possible when there was cheap enough computing power to allow good analysis

Yeah - I'm normally a fan of "good old" stuff, which I can normally pick up cheap (if I wait long enough).

But a few fields have been so transformed by cheap computer power, that the old stuff is rubbish by comparison. Optics (camera lenses, telescopes, binoculars) have been transformed. To the extent, of course, that some people use the old stuff for "artistic" reasons. c.f. Lomo.

BugBear

 

[Racers]

I recovered the grills on my Shahinian Arcs and put a chamfer on all the internal edges of about 3mm, it did sound better afterwards.

Pete

 

[Beau]

I wonder how many people (without the use of very sensitive instrumentation) could tell the audible difference between a plywood, MDF, Padauk, Walnut, etc.. speaker cabinet.

I'll stick my neck out and say, absolutely none.

It's amazing the subtleties you can hear. Not done comparisons on cabinets but speaker cable can make a world of difference and they are all basically just copper. Got loaned three sets of speaker cable to try in exchange for some woodwork I had done for Peter Comeau (he was a hifi reviewer at this stage). Was poo pooing the idea that I would notice any difference but gave them a ago. I played the same three tracks with each cable and did not notice any difference between the first two and wondered off into the next room when I had plugged the third set in. Sitting in the room with some family and we all noticed the difference from a room away. The difference was like chalk and cheese. Turned out they were the most expensive unsurprisingly but still got them for the woodwork I had done. £95 a meter and I got 2 x 7.5m runs! that was one of my better barters.

 

[novocaine]

I wonder how many people (without the use of very sensitive instrumentation) could tell the audible difference between a plywood, MDF, Padauk, Walnut, etc.. speaker cabinet.

I'll stick my neck out and say, absolutely none.

It's amazing the subtleties you can hear. Not done comparisons on cabinets but speaker cable can make a world of difference and they are all basically just copper. Got loaned three sets of speaker cable to try in exchange for some woodwork I had done for Peter Comeau (he was a hifi reviewer at this stage). Was poo pooing the idea that I would notice any difference but gave them a ago. I played the same three tracks with each cable and did not notice any difference between the first two and wondered off into the next room when I had plugged the third set in. Sitting in the room with some family and we all noticed the difference from a room away. The difference was like chalk and cheese. Turned out they were the most expensive unsurprisingly but still got them for the woodwork I had done. £95 a meter and I got 2 x 7.5m runs! that was one of my better barters.

then it turns out the best you can use is twin and earth.

 

[Beau]

I wonder how many people (without the use of very sensitive instrumentation) could tell the audible difference between a plywood, MDF, Padauk, Walnut, etc.. speaker cabinet.

I'll stick my neck out and say, absolutely none.

It's amazing the subtleties you can hear. Not done comparisons on cabinets but speaker cable can make a world of difference and they are all basically just copper. Got loaned three sets of speaker cable to try in exchange for some woodwork I had done for Peter Comeau (he was a hifi reviewer at this stage). Was poo pooing the idea that I would notice any difference but gave them a ago. I played the same three tracks with each cable and did not notice any difference between the first two and wondered off into the next room when I had plugged the third set in. Sitting in the room with some family and we all noticed the difference from a room away. The difference was like chalk and cheese. Turned out they were the most expensive unsurprisingly but still got them for the woodwork I had done. £95 a meter and I got 2 x 7.5m runs! that was one of my better barters.

then it turns out the best you can use is twin and earth.

Not even close to these Audiquest ones

 

[Eric The Viking]

Pete mentions two schools of design above - rigid enclosure and allowing the cab itself to radiate. My understanding is that the latter only became possible when there was cheap enough computing power to allow good analysis

Yeah - I'm normally a fan of "good old" stuff, which I can normally pick up cheap (if I wait long enough).

But a few fields have been so transformed by cheap computer power, that the old stuff is rubbish by comparison. Optics (camera lenses, telescopes, binoculars) have been transformed. To the extent, of course, that some people use the old stuff for "artistic" reasons. c.f. Lomo.

BugBear

I'm hoping to get a new 12mm lens (for panoramas) in the new year, a Laowa. The optical performance is amazing for the price, considering the image circle (for full-frame). It has several aspherical elements. Laowa explain that it's in part down to computing power.

 

[Eric The Viking]

... I'll stick my neck out and say, absolutely none.

... It's amazing the subtleties you can hear. Not done comparisons on cabinets but speaker cable can make a world of difference and they are all basically just copper.

then it turns out the best you can use is twin and earth.

Apologies if I have attributions muddled above.

Loudspeaker cables making an improvement is down to simple physics/electronics. The lower the cable impedance, the better that low-impedance speaker systems work. Fit thicker cable and it will really work better, because the cable resistance (impedance) is lower. You can use any heavy cable and hear an improvement over bellwire.

As to whether 95 quid/m is value for money, however...

OTOH mains leads for HiFi, almost by definition, make no difference whatsoever, neither does microphony in speaker cables.

As far as esoterica goes, I'd really like a pair of Ionofane tweeters, just to try them out. But now we have a grandchild there are safety implications, sadly.

 

[novocaine]

then it turns out the best you can use is twin and earth.

Not even close to these Audiquest ones[/quote]

was meant as a joke Beau.

will say though that it is surprising how go T+E is at being a speaker cable, think it was what hifi who did a test on it and it came out on the upper end of the spectrum for quality of sound.

 

[bugbear]

Long ago, I used cooker cable as speaker cables. Sounded great. Far too rigid to be convenient though. Decent cost/benefit ratio.

Added; System was: Roxan Xerxes, Armstrong PCU25, Armstrong A20, Spendor Prelude

BugBear

 

[Beau]

then it turns out the best you can use is twin and earth.

Not even close to these Audiquest ones

was meant as a joke Beau.

will say though that it is surprising how go T+E is at being a speaker cable, think it was what hifi who did a test on it and it came out on the upper end of the spectrum for quality of sound.[/quote]


Sorry I am not the best at picking up written subtleties. Yes I use T+E for my workshop system and perfectly acceptable. I would never spend a fortune on cables but when they fall in your lap what can you do.

 

[Racers]

My present speaker cable (actually 4 wires) came out of the skip at work a part used reel of 16mm CSA try rated wire.
It needed a blow torch to solder the ends, I use spades at the speaker and 50A Anderson connectors on my power amps.

Pair of Hackernaps by Racers, on Flickr

16mm CSA is rated at 90A continuous, so they don;t even get warm!

T+E dosn't have enough strands to sound good, it will give you lots of midrange but not much else, it can make systems with problems sound good.

Pete

 

[DTR]

T+E dosn't have enough strands to sound good, it will give you lots of midrange but not much else, it can make systems with problems sound good.

Pete

Ok, I'll bite. Why does the number of strands make a difference?

(electrically speaking, that is. Obviously it would be more flexible)

 

[NazNomad]

It's perceived snobbery. if you spend £500 on a piece of wire, your brain will definitely hear the difference.

The same when you spend a Million squids on a car, it'll be so much better than a £500k one (in the mind of the purchaser).

Take a big swig of James Randi's Snake Oil and call me in the morning if you still feel the same.

Q: How can you tell if someone has £7,000 speakers?
A: Don't worry, they'll tell you.