The Driver/Enclosure relationship

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jimbob
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The Driver/Enclosure relationship

Unread post by jimbob »

Are there any guidelines for the size of the enclosure required for specific driver sizes, or is it driver specific?

Also, how can I tell if a driver is suitable for a sealed enclosure rather than a ported one? I think it has something to do with the surround compliancy but I could be wrong...
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Re: The Driver/Enclosure relationship

Unread post by Vinyl-ant »

Rod elliots website is a good source of info, he has loads of information and resources on a number of subjects, and is well written
Here's the bit of the site regarding speaker design

https://sound-au.com/articles/enclosures.htm
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savvypaul (Fri May 01, 2020 2:25 pm)
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Re: The Driver/Enclosure relationship

Unread post by valvesRus »

Most loudspeaker drive units have what are called "thiele - small parameters". These are sets of figures that can tell one how a drive unit may work in certain conditions.

Using them won't get you a perfect loudspeaker first time, but you might get 90% of the way there without loads of woodwork.

There are (on other forums) those, who given the thiele - small parameters and an idea of what you want to achieve, could point you in the right direction.

Unfortunately, Richard Dunn had a very poor opinion of such "experts" and regularly lambasted one poor chap, who is a friend of mine, and has helped hundreds of enthusiasts to experience excellent sound in their home hi fi systems.

http://audiojudgement.com/thiele-small- ... explained/

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Re: The Driver/Enclosure relationship

Unread post by jimbob »

Thanks chaps! I will check out both those links.
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Re: The Driver/Enclosure relationship

Unread post by savvypaul »

valvesRus wrote: Fri May 01, 2020 12:10 pm Unfortunately, Richard Dunn had a very poor opinion of such "experts" and regularly lambasted one poor chap, who is a friend of mine, and has helped hundreds of enthusiasts to experience excellent sound in their home hi fi systems.

http://audiojudgement.com/thiele-small- ... explained/
ADMIN - take your anti RD agenda elsewhere (if you still can't get over it). This is your second and final warning. One more transgression and you are out of here.
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Re: The Driver/Enclosure relationship

Unread post by SteveTheShadow »

jimbob wrote: Fri May 01, 2020 11:22 am Are there any guidelines for the size of the enclosure required for specific driver sizes, or is it driver specific?

Also, how can I tell if a driver is suitable for a sealed enclosure rather than a ported one? I think it has something to do with the surround compliancy but I could be wrong...
https://www.diyaudioandvideo.com/Calcul ... Enclosure/

https://www.diyaudioandvideo.com/Calcul ... peakerBox/

This site is superb. There are all sorts of useful tutorials.
Speaker design can be problematic because of the amount of bullshit you have to wade through to get anywhere fast but the above two links are relatively free of nonsense, will short circuit the claptrap and will help you to get great sound. Thiele Small parameters are your friend.
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savvypaul (Fri May 01, 2020 1:51 pm) • Lindsayt (Fri May 01, 2020 2:20 pm) • jimbob (Fri May 01, 2020 3:00 pm)
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Re: The Driver/Enclosure relationship

Unread post by Daniel Quinn »

Use the measurements as a guide But don't forget to listen. If you design loudspeakers via measurement, you may as well buy thin floorstander with a small driver and bass reflex loaded.

Sealed enclosures and large magnets are in my opinion the most important parameters.
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Lindsayt (Fri May 01, 2020 4:50 pm)

valvesRus
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Re: The Driver/Enclosure relationship

Unread post by valvesRus »

Daniel Quinn wrote: Fri May 01, 2020 4:28 pm Use the measurements as a guide But don't forget to listen. If you design loudspeakers via measurement, you may as well buy thin floorstander with a small driver and bass reflex loaded.

Sealed enclosures and large magnets are in my opinion the most important parameters.
There is also the view that the best box for a loudspeaker, is no box at all.

I'm a fan of OB (open back or open baffle) speakers myself ,but they are not to everyone's taste.

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Re: The Driver/Enclosure relationship

Unread post by Docfoster »

valvesRus wrote: Fri May 01, 2020 12:10 pm Most loudspeaker drive units have what are called "thiele - small parameters". These are sets of figures that can tell one how a drive unit may work in certain conditions.

Using them won't get you a perfect loudspeaker first time, but you might get 90% of the way there without loads of woodwork.

There are (on other forums) those, who given the thiele - small parameters and an idea of what you want to achieve, could point you in the right direction.
There are on-line Thiele perameter calculators for both sealed and ported volumes. Here’s one:

http://www.micka.de/en/

Plenty of acoustic variables beyond Thiele numbers (system, room, ears), and obviously ears are the *only* ultimate arbiter. But good luck building a succession of cabinets in increments of single litres so you can do it 100% subjectively.
I think for a from-scratch build you’d be pretty insane to use anything other than the Thiele perameters to calculate at least a starting point, if you have them.
IME Thiele perameters for older drivers are difficult to get hold of, though sometimes it’s possible to find a recommended cabinet volume for an ancient driver in some old manufacturer’s brochure that some kind soul has preserved, scanned and put on the internet.
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savvypaul (Fri May 01, 2020 6:01 pm)
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Re: The Driver/Enclosure relationship

Unread post by Geoff.R.G »

valvesRus wrote: Fri May 01, 2020 12:10 pm Richard Dunn had a very poor opinion of such "experts"
Richard's opinion on "experts" was well known but with, I understand, good reason. Far too many people subscribe to the idea that you can measure everything that matters. This is not the case, many important things cannot be measured. Einstein is reputed to have stated “Not everything that counts can be counted, and not everything that can be counted counts.”

I don't believe that any musical device can be designed without the use of that most of important of instruments, the human ear. That was Richard's mantra and he was right.
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