SLOB project

Dedicated to those large boxes at one end of the room
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Ray P
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#16 Re: SLOB project

Post by Ray P »

I found the datasheet for the units I'm buying;

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Ray P
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#17 Re: SLOB project

Post by Ray P »

Except that I've now realised that some of the parameters are different! I'm buying the Fast-10S, the datasheet is for the Fast-10.
Last edited by Ray P on Tue Dec 17, 2019 8:54 pm, edited 1 time in total.
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#18 Re: SLOB project

Post by simon »

I think the website you linked to suggested there was no material difference between 10 and 10S?
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Ray P
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#19 Re: SLOB project

Post by Ray P »

simon wrote: Tue Dec 17, 2019 8:43 pm I think the website you linked to suggested there was no material difference between 10 and 10S?
Yes, but I've also seen reference to the Fast-10S being an upgrade and some of the numbers do appear to be different. Not that I can change any of it of course.
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#20 Re: SLOB project

Post by IslandPink »

Ray P wrote: Mon Dec 16, 2019 9:55 pm
Before I get to thinking about acrylic though it'll have to be some MDF or cheap ply for the baffle to get some level of confidence in the outcome before spening out that sort of money.
Good that you're going for the big baffle as shown in Nelson's article - respect !
I would not use MDF for a baffle holding a midrange driver - even for testing. It has nasty resonances in the upper vocal areas . Use cheap ply or chipboard. I used chipboard for an earlier version of the Quasars I built.
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#21 Re: SLOB project

Post by IslandPink »

The numbers on the variants of the 10" unit look fairly similar. Not much to make any design different. Just a slight difference in the crossover position/slope when you get to that.
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#22 Re: SLOB project

Post by simon »

Second what Mark says about mdf and open baffles - nasty in my limited experience. Only used it because the yard didn't have any chipboard, but for the little additional I should have gone for a cheaper ply.
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#23 Re: SLOB project

Post by Ant »

Another one for chipboard, my fanes are a mix of chipboard and ply. Ime Mdf is fine for small panels and oddly shaped panels, but crap for big panels.
Those drivers look quite good for sealed boxes too by the looks of the numbers
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Ray P
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#24 Re: SLOB project

Post by Ray P »

IslandPink wrote: Tue Dec 17, 2019 10:15 pm Good that you're going for the big baffle as shown in Nelson's article - respect !
Mark, we may be at cross-purposes but I'm not building the OB shown in Nelson's article, not if you're thinking of this one;

http://www.enjoythemusic.com/diy/0911/s ... peaker.htm

That would be just to large even for my reasonably sized (for the UK - about 16ft x 14ft) living room. This is the Nelson-designed SLOB I'm working towards;
Pass SLOB.jpg
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Last edited by Ray P on Wed Dec 18, 2019 6:41 am, edited 1 time in total.
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Ray P
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#25 Re: SLOB project

Post by Ray P »

and here are the drawings;
Pass SLOB Part 1.gif
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Ray P
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#26 Re: SLOB project

Post by Ray P »

I'll make up some initial baffles to those dimensions, sans bass units, from some cheap ply when the drive units arrive. Thanks for the tips about avoiding MDF.
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#27 Re: SLOB project

Post by IslandPink »

Also good !
About the same area as a Quasar actually.
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#28 Re: SLOB project

Post by steve s »

Looks a good design to me Ray I would guess they will give good results
I would damp the rear / internal panels as in my experience they will sound cleaner, but that's up to you of course.
Your Lowthers may work well in them,
better than the 10's you are looking at although those 10s look amazingly flat.
I have a few vintage full range 10" drivers, they are better than 8s from a full range perspective, but from 250 Hz up I stick with 8s.
I would fit an 18" driver in for bass duties.. but again that's just my experience.
Looking forwards to your build..
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#29 Re: SLOB project

Post by ed »

Hi Ray

I've thought that design looked interesting for a while but my distain for OBs in my small room always put me off.
However I have some 12" sovereigns and 8" Betsys left over from my previous OB attempts which I might try with some carcass ply. They are just gathering dust so I may as well put them in something as I know I'd struggle to sell them....

thanks for reminding me about this.
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#30 Re: SLOB project

Post by Ali Tait »

Having used both 15” and 18” in OB’s, I’d agree 18” is much better.
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