| Author |
Message |
|
Chompy191
Joined: Sat Apr 21, 2012 9:17 pm Posts: 45 Location: SA, Aus
|
 SLA BMR drivers
Hey all, Planing to build a sla centre and possibly tlah mains sometime soon. Found a new possible driver on parts express. Hiwave 3.5" balanced mode radiator full range speakers which weigh 0.3lbs each for reasonable shipping to Aus. Not really sure about BMR drivers and wondering what people think about feasibility in a SLA or TLAH. http://www.parts-express.com/pe/showdet ... r=297-2156http://www.hi-wave.com/downloads/datash ... C20F-8.pdf
_________________ TTLS 17" THT 24.5" SLA LCR
Last edited by Chompy191 on Fri Dec 07, 2012 8:25 pm, edited 2 times in total.
|
| Sat Oct 20, 2012 12:25 am |
|
 |
|
Bill Fitzmaurice
Site Admin
Joined: Tue May 02, 2006 5:59 pm Posts: 21644
|
 Re: SLA / TLAH BMR drivers?
Looks fine except for the midrange dip. It should be able to run full range.
|
| Sat Oct 20, 2012 7:41 am |
|
 |
|
gzc_stageTech
Joined: Thu Oct 05, 2006 7:31 pm Posts: 288 Location: Wichita, KS
|
 Re: SLA / TLAH BMR drivers?
What the heck is, "bending wave technology and pistonic operation"? Somebody in sales must be using a thesaurus. Or the tech staff just got tired of going unnoticed.
|
| Sat Oct 20, 2012 8:04 am |
|
 |
|
Alien
Joined: Tue Oct 30, 2007 7:29 pm Posts: 74 Location: Milton Keynes, England
|
 Re: SLA / TLAH BMR drivers?
685g is closer to 1.5 lb - might well be a deal breaker A
|
| Sat Oct 20, 2012 11:03 am |
|
 |
|
Chompy191
Joined: Sat Apr 21, 2012 9:17 pm Posts: 45 Location: SA, Aus
|
 Re: SLA / TLAH BMR drivers?
Balanced Mode Radiator (BMR), a hybrid technology that blends DML technology with that of traditional pistonic-action loudspeakers.[3] According to NXT, the resultant speakers feature the low-frequency performance of a traditional loudspeaker, but with a wider directivity and shallower profile, as well as the mid-range and high-frequency performance of a DML. Distributed Mode Loudspeaker (DML) is a flat panel loudspeaker technology, developed by NXT[citation needed], in which sound is produced by inducing uniformly distributed vibration modes in the panel through a special electro-acoustic exciter Source http://en.wikipedia.org/wiki/Distribute ... oudspeakerSo from what I can determine these use the hybrid technology so for the mids and highs use the DML technology with much wider dispersion. So these would eliminate the need for tweeters? (would save a heap of money). Might have to order some before parts express change the listed weight. Cambridge minx speakers use BMR drivers, worth a read. http://www.cambridgeaudio.com/assets/do ... _Paper.pdf
_________________ TTLS 17" THT 24.5" SLA LCR
|
| Sat Oct 20, 2012 6:26 pm |
|
 |
|
Bill Fitzmaurice
Site Admin
Joined: Tue May 02, 2006 5:59 pm Posts: 21644
|
 Re: SLA / TLAH BMR drivers?
There's a lot of gobbledygook there, whereas the explanation is quite simple. Rather than using a cone shape to stiffen the diaphragm so that it doesn't flex it uses a flat honeycomb diaphragm. Being flat it doesn't suffer as much from phase issues as a cone, so high frequency dispersion is wider. The downside is that a honeycomb diaphragm has higher mass than a cone, so there's a loss of sensitivity, which grows worse exponentially as the diaphragm is made larger, so it only works well with smaller drivers. And it's more expensive to build than a cone driver, but if you can get them on closeout that's not an issue.
|
| Sat Oct 20, 2012 6:56 pm |
|
 |
|
Chompy191
Joined: Sat Apr 21, 2012 9:17 pm Posts: 45 Location: SA, Aus
|
 Re: SLA / TLAH BMR drivers?
Hmm, my plan so far is 6 drivers per cab wired to 12 ohm to stay within my budget with no tweets or crossover. The drivers have 81db sensitivity so with 6 I guess sensitivity will be high enough. Would there be any benefit building floor standing rectangular tlah's with 6 drivers rather than SLA's for mains?
_________________ TTLS 17" THT 24.5" SLA LCR
|
| Sat Oct 20, 2012 11:22 pm |
|
 |
|
DJPhatman
Joined: Mon Aug 14, 2006 5:08 am Posts: 3724 Location: Warren, Michigan
|
 Re: SLA / TLAH BMR drivers?
Could you somehow squeeze the 6 extra into your budget, to do 9 per TLAH? For an extra $40 or so, the results will amaze you.
_________________ Accept the fact that airtight and well-braced are more important than pretty on the inside. If you can't find the time and money to do it right the first time, how will you find the time and money to do it right a second time?
|
| Sun Oct 21, 2012 3:24 am |
|
 |
|
Chompy191
Joined: Sat Apr 21, 2012 9:17 pm Posts: 45 Location: SA, Aus
|
 Re: SLA / TLAH BMR drivers?
An extra $90 for 6 more speakers with shipping expenses, but if the difference is that much then I might just go for it. Just still a bit unsure about sensitivity 81 db per driver, 6 driver sla and 9 driver tlah. Not too much difference in sensitivity between them? Should be all good with these BMR drivers for no tweeters. Otherwise I'm good to go.
_________________ TTLS 17" THT 24.5" SLA LCR
|
| Sun Oct 21, 2012 5:48 am |
|
 |
|
DJPhatman
Joined: Mon Aug 14, 2006 5:08 am Posts: 3724 Location: Warren, Michigan
|
 Re: SLA / TLAH BMR drivers?
 My bad, I forget, more than sometimers, that not all on the forum are in the USA. 
_________________ Accept the fact that airtight and well-braced are more important than pretty on the inside. If you can't find the time and money to do it right the first time, how will you find the time and money to do it right a second time?
|
| Sun Oct 21, 2012 11:42 am |
|
 |
|
mpm
Joined: Mon Oct 08, 2007 3:30 pm Posts: 14 Location: Alabama
|
 Re: SLA / TLAH BMR drivers?
Those look interesting. I'm currently trying to convince the war and finance department I gotta have these. Plans are for 2 SLA's and one curved SLA with 8 or 9 per cabinet. Thanks for the find.
|
| Mon Oct 22, 2012 9:03 pm |
|
 |
|
Chompy191
Joined: Sat Apr 21, 2012 9:17 pm Posts: 45 Location: SA, Aus
|
 Re: SLA / TLAH BMR drivers?
Good buy for anyone outside of the US. Ordered 20 and only cost $80 in shipping which is very good. Going 6 drivers per cab, probably all SLA since i'll be using these in my bedroom mainly. Not sure if it will be of any benefit building a curved centre due to the wide dispersion of these drivers. Will be making some small bookshelf speakers with the extra 2 for my pc so if anyone knows any good designs? and to practice finishing
_________________ TTLS 17" THT 24.5" SLA LCR
|
| Tue Oct 23, 2012 6:06 am |
|
 |
|
DJPhatman
Joined: Mon Aug 14, 2006 5:08 am Posts: 3724 Location: Warren, Michigan
|
 Re: SLA / TLAH BMR drivers?
 This makes no sense. The dispersion of this driver is no different than any other driver of the same size. Where are you getting dispersion figures? This driver will benefit from a curved center SLA.
_________________ Accept the fact that airtight and well-braced are more important than pretty on the inside. If you can't find the time and money to do it right the first time, how will you find the time and money to do it right a second time?
|
| Tue Oct 23, 2012 10:33 am |
|
 |
|
Bill Fitzmaurice
Site Admin
Joined: Tue May 02, 2006 5:59 pm Posts: 21644
|
 Re: SLA / TLAH BMR drivers?
Read my earlier post. But the function of the CurveArray has nothing to do with the dispersion of the individual drivers employed.
|
| Tue Oct 23, 2012 11:07 am |
|
 |
|
DJPhatman
Joined: Mon Aug 14, 2006 5:08 am Posts: 3724 Location: Warren, Michigan
|
 Re: SLA / TLAH BMR drivers?
So, how does the flat diaphragm, that is approximately 100mm in diameter, produce a 6000Hz sound wave that is ~57.17mm in length, let alone 12,000Hz which is ~2.85mm in length? This is the part that makes no sense to me.
_________________ Accept the fact that airtight and well-braced are more important than pretty on the inside. If you can't find the time and money to do it right the first time, how will you find the time and money to do it right a second time?
|
| Tue Oct 23, 2012 11:32 am |
|
|