Might wanna consider beaming at the upper end with an 8" driver unless directivity is the goal. Even 6.5" is pushing it IMO. A pair of 5" drivers might be better suited to the task....depending on what the task is. B&C has a great 6.5" Pro mid with 95db sensitivity that would work in the FR range you specified and it's only $70 with pretty low HD and very high power handling.
http://zaphaudio.com/6.5test/compare.html
http://zaphaudio.com/6.5test/compare.html
mayhem13 said:
But double mids may have lobing issues, if crossed high
With high efficient drivers you could choose a midwoofer, but it wont do he highs
Or you could choose a mid, but it wont do the lows
I dont know why, but Beta-8A seem to cut it where all other fails
if company specs are to be trusted
Defo said:
- 200 - 2500 khz
Any recommendations?
Defo said:
That's not good because of Fs (is) too close, (that) you don't want. Response looks +/- good at 200Hz. It doesn't have a smooth rolloff with a peack of ~8dB at 5kHz.
http://www.parts-express.com/pdf/294-651.pdf
Attachments
The peak at 5khz is negligable, and a fair tradeoff for what you get otherwise. Given an LR4 at 2.5khz you'd never be able to isolate it during listening.
There's plenty of great 6.5" mids in the Pro audio world but if efficiency isn't the goal i'd go 5". The SEAS MCA15RCY is an exceptional mid driver
Why not cross it higher to the woofer, say 400hz or so. If the design is high efficiency, there's plenty of Pro woofers that can do 400hz in their sleep.
There's plenty of great 6.5" mids in the Pro audio world but if efficiency isn't the goal i'd go 5". The SEAS MCA15RCY is an exceptional mid driver
Why not cross it higher to the woofer, say 400hz or so. If the design is high efficiency, there's plenty of Pro woofers that can do 400hz in their sleep.
Re: Re: Re: Hi efficiency 8 inch midrange - recommendations?
8NMB420
B&C 8NDL51
Look at Brandon's measurements and see what you think.Defo said:
8NMB420
B&C 8NDL51
mayhem13 said:
What people often forget is that a steep xover slope only fixes a portion of the problem. The signal being sent to the driver would be 24dB down at 5KHz in this example. The problem is that you still have the physical resonance there that the xover does nothing to fix. A high 2nd harmonic of 2.5KHz or 3rd harmonic of 1.25Khz created by the driver alone would not be affected by the xover. The 5KHz resonance can be excited to very audible levels without ever sending a 5KHz signal to it.
John
a.wayne said:
I've measured my 21" Beyma, its actually better than the Seas W22 when it comes to THD at the same SPL at 300 Hz.
JBL (to name just one manufacturer) is able to use 15" drivers successfully into the 1 kHz range, so I would think that it is possible indeed. In their Project Everest, they run one 15" up to 700 Hz. Would you say that speaker is a faulty design?
a.wayne said:
You must not have heard any good 15" drivers. Our TD15M is flat to 4KHz where it then rolls off nicely without any harsh breakup. By 10KHz it is only about 12dB down. We actually do a variant and EQ it flat to 10KHz to play in bass guitar cabinets.
In the midrange and vocal region, the large drivers will sound much better as they have to only move a fraction as far as a smaller driver to get the same SPL. Much lower input power means much lower thermal distortion issues. It also means less flux modulation and less inductance variation with excursion.
The only thing you need to worry about is your required dispersion pattern. Due to the nature of the larger drivers you will have a more narrow pattern, but at 2KHz you are still fairly good to 30 degrees off axis in any given direction. At 1KHz you can go to 45degrees giving you a 90 degree coverage pattern that will mate nicely with many waveguides there.
MisterTwister said:
It can be excited by higher order harmonics as well depending on their levels. The higher order harmonics are also typically more offensive to the hearing.
John
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