Looking at the spec sheets which can be found here my guess is SP1054, am I right? Does it make a big difference??
Ah ok - I should have said, sorry. This would be for a 2 ft3 bass reflex (similar to a BBC LS3/6 or a Spendor BC1)
That snapshot looks to be from my site: Those data sheets were scanned from the KEF blue binder i got from KEF. That predates the 3 screw B200, which isn’t really much the same.
As Galu suggests it depends on your application.
I do question SP1014 in small oxes (i have heard some and they sound good (Tangent TM-3), but i have 16 of them and modeling suggests a MUCH larger box required.
Note that other than the SP1014, none of the others were available to diyers so are much harder to find.
dave
As Galu suggests it depends on your application.
I do question SP1014 in small oxes (i have heard some and they sound good (Tangent TM-3), but i have 16 of them and modeling suggests a MUCH larger box required.
Note that other than the SP1014, none of the others were available to diyers so are much harder to find.
dave
Thanks a lot Dave and Galu, I appreciate it!
So Dave, are you saying SP1014 might work well in a 2 cu ft reflex enclosure? Could you also explain why SP1022 and SP1054 both say 50L but have different cu ft values please? I'm inclined towards SP1054 for the lower Q (low is better, right? Or is that an oversimplification? Which would you choose? Sorry for the noob questions..
P.S. Thank you so much for uploading the spec sheets in the first place and sorry I didn't credit you in my initial post.
So Dave, are you saying SP1014 might work well in a 2 cu ft reflex enclosure? Could you also explain why SP1022 and SP1054 both say 50L but have different cu ft values please? I'm inclined towards SP1054 for the lower Q (low is better, right? Or is that an oversimplification? Which would you choose? Sorry for the noob questions..
P.S. Thank you so much for uploading the spec sheets in the first place and sorry I didn't credit you in my initial post.
Thanks a lot Dave.
It's a bit of a change of subject but I'm guessing you're into Transmission Line speakers? I recently got a pair of IMF ALS30s - they are Active Line rather than Transmission Lines but I thought you might be interested.
It's a bit of a change of subject but I'm guessing you're into Transmission Line speakers? I recently got a pair of IMF ALS30s - they are Active Line rather than Transmission Lines but I thought you might be interested.
Strange, there seems to be a mistake in conversion regarding the SP1054.
Assuming the litre values to be correct, its reflex cubic foot values are incorrectly calculated and should be 1.4 (40 L) and 1.8 (50L).
EDIT: And the SP1022 delights in stretching 1.8 cu ft (50 L) to 2.0 cu ft!
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As a general guideline, Qts of 0.4 or below indicates suitability for a reflex enclosure. Qts between 0.4 and 0.7 indicates suitability for a sealed enclosure.
So the SP1054 qualifies for reflex at 0.23, while the SP1022 can also be said to qualify at 0.41.
56 litres sealed has Q=0.933. Based on numbers supplied by KEF.
So sealed and stuff it a lot.
dave
So sealed and stuff it a lot.
dave
Thanks Dave - I was specifically setting out to build a BC1-style 8” driver in a 2 cubic foot vented box.
I saw a Graham Audio LS8 in a shop and loved it but can’t afford it, so I went home and started reading about the history of the BBC Research Department and thin wall cabinets, bextrene cones, Spendor, Rogers, Harbeth etc. and decided to learn how to build my own. I’m clearly not quite there yet and I appreciate all the help you’re giving me, but it’s got to be a 24”x12” reflex enclosure, nothing else will do.
I saw a Graham Audio LS8 in a shop and loved it but can’t afford it, so I went home and started reading about the history of the BBC Research Department and thin wall cabinets, bextrene cones, Spendor, Rogers, Harbeth etc. and decided to learn how to build my own. I’m clearly not quite there yet and I appreciate all the help you’re giving me, but it’s got to be a 24”x12” reflex enclosure, nothing else will do.
Given that B200 sounded good in Tangent TM1 and TM3 that is a strange and unexpected value.
And definitly larger than KEF suggests.
Can someone double check… i used the numbers from here:
dave
Given th enumbers above there is no BR that works.
BTW sealed, F10 is ib the low 20s, F6 30.
The sims do not match what was done in the field in the 70s.
It might explain why SP1014 worked so welll in IMF TLS50.
dave
That’s a shame, I thought I was getting somewhere! How would I go about finding a suitable 8” mid-bass for a ~2 cu for reflex enclosure then? I’m not asking you to do the work for me - is there a good resource that you know to help a beginner like me understand all this stuff? Thanks again.
Why? The B200 sealed goes lower and has a lower order roll-off. But if you find that the bass lift at the bottom is too much you can add an aperiodic vent to work towards flattening it out.
If you have B200 already, try it.
If you have to have a reflex, I know of no other way than picking all the 8” you find interesting, that are within your budget and plug them into a simulator and se if you can come up with a decent alignment.
dave