B&C Compression Driver and Horns

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Well i'm tossing up whether to get into horns or not and have been doing a little research. The concept of compression horn speaker interests me.

So far I have found the B&C DE950

Has anyone heard of these drivers?

I also like the look of the PHL 5240 15" Driver for bass.

As for tweeters I haven't thought to much about it yet. Perhaps the Visaton TL 16H.


Any ideas, opinions and suggestions would be more than appreciated.

Cheers
 
Thanks for the replies guys.

I have quite a good Scan-speak based system and want to try something totally different. In terms of why i'm after horns is basically because I want a pair of Advantgardes but can't afford them. So i'm looking at DIY alternatives.

If the B&C drivers don't look the best can anyone recommend some alternative drivers?

Cheers
 
If this is for a home system, unless you absolutely need the compression driver to play below 1 kHz or so, there's no reason to go with the 3-4" diaphram drivers... use a 1" exit 1.5-2" diaphram driver. The larger diaphram drivers like the one you linked have resonances low enough in frequency that they are a problem. For smaller drivers this is usually up at at least 15k or so... much less of a problem. The B&C DE250 would be a good choice for example. You can mate this to a 15 if you have a horn large enough to control the directivity down to 1 kHz or so.
 
gni said:
Three impedance peaks. . .there are better experts out there
but it seems strange. . .probably the design. . .it should be
crossed higher that the low peak. The peaks almost look
like a wooker in a ported enclosure.

A compression driver IS dual resonance system, just like a ported speaker, but its actually in a bandpass configuration. Thats why there are TWO peaks. The third one should not be there in a good waveguide design.


warnsey said:
Thanks for the replies guys.

I have quite a good Scan-speak based system and want to try something totally different. In terms of why i'm after horns is basically because I want a pair of Advantgardes but can't afford them. So i'm looking at DIY alternatives.

If the B&C drivers don't look the best can anyone recommend some alternative drivers?

Cheers

I like B&C drivers a lot. They are as good as anybody elses, and better than nost. Why "try something totally different" there are lots of good existing designs that have had a lot of engineering put into them.

augerpro said:
I think the peaks are caused mostly by the horn used. Use a different horn and you'll probably get different peaks.

You can get different peaks, but if the waveguide is design correctly then there should be very little change in the peaks. They are mostly caused by the driver. If there are a lot of peaks then something is seriuosly wrong with the design. There should be two, very clean peaks.

Rybaudio said:
If this is for a home system, unless you absolutely need the compression driver to play below 1 kHz or so, there's no reason to go with the 3-4" diaphram drivers... use a 1" exit 1.5-2" diaphram driver. The larger diaphram drivers like the one you linked have resonances low enough in frequency that they are a problem. For smaller drivers this is usually up at at least 15k or so... much less of a problem. The B&C DE250 would be a good choice for example. You can mate this to a 15 if you have a horn large enough to control the directivity down to 1 kHz or so.


I would completely concur here that the larger format drivers are for power handling ONLY and they innevitably have poorer HF response. The 1" is ideal for a home system since it can reach from 1 kHz to beyond audible thus leaving out the very messy crossover in the critical range of 2-8 kHz.

Waveguides are the way to go, but only if done correctly. Do it wrong, which is more typical than right, and they can be horrible. This is how they got their bad name.
 
gedlee said:


A compression driver IS dual resonance system, just like a ported speaker, but its actually in a bandpass configuration. Thats why there are TWO peaks. The third one should not be there in a good waveguide design.




I like B&C drivers a lot. They are as good as anybody elses, and better than nost. Why "try something totally different" there are lots of good existing designs that have had a lot of engineering put into them.



You can get different peaks, but if the waveguide is design correctly then there should be very little change in the peaks. They are mostly caused by the driver. If there are a lot of peaks then something is seriuosly wrong with the design. There should be two, very clean peaks.




I would completely concur here that the larger format drivers are for power handling ONLY and they innevitably have poorer HF response. The 1" is ideal for a home system since it can reach from 1 kHz to beyond audible thus leaving out the very messy crossover in the critical range of 2-8 kHz.

Waveguides are the way to go, but only if done correctly. Do it wrong, which is more typical than right, and they can be horrible. This is how they got their bad name.


Thank you very much for the lengthy response. So perhaps the B&C DE500 would be a better bet. You mentioned that there are good existing designs out there (I assume you mean using compression drivers) is there any chance you could point me in the right direction?

Cheers
 
The DE500 is a pretty nice little driver. I used them in my car a while back. Nice small drivers.

I believe that Dr. Geddes also likes it's little brother the DE250 quite a bit too. I haven't used the 250, but have used the 200 a while back. The 200 may have a little better treble than the 500, but the midrange of the 500 was better IMO.
 
warnsey said:



Thank you very much for the lengthy response. So perhaps the B&C DE500 would be a better bet. You mentioned that there are good existing designs out there (I assume you mean using compression drivers) is there any chance you could point me in the right direction?

Cheers


I do like the DE250 a lot. I've used the DE500, and its size is a real asset. But its not worth the extra cost in my opinion.

"there are good existing designs out there (I assume you mean using compression drivers) " - I can't find where I said that, but I doubt that I meant the driver. There are plenty of good drivers out there. There are almost no good waveguides (mine work well), so I suspect thats what was meant.
 
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gedlee said:



That could work, but the extra 1.5 dB of the DE250 is almost required when using the higher efficiency woofers. It would probably work with the 10" however. I might have to look into that if its cheaper. If its not a lot cheaper then I would just stick to the 250 for all the systems.


You have been also calculating waveguide foam plugTM losses in the above estimation I suppose.
 
salas said:



You have been also calculating waveguide foam plugTM losses in the above estimation I suppose.


The foam losses are not that significant, but they are there. The real problem is with CD. My waveguides control directivity all the way to about 16 kHz (because the driver dies not because of the waveguide). This means that the axial response drops quite a bit - theoretically it should drop at -6 dB/oct after resonance (and that assumes NO inductance). That means that using one of my waveguides, at 10 kHz the compression driver just makes the efficiency of the bigger woofers - and the foam doesn't help! The DE250 just gets there, I'm not sure the DE160 would.
 
salas said:
If he will opt for a real CD, then things are tight indeed SPL wise. Did you design for B&C? I have used them and liked them. Big ones also.

I used to work for B&C and I knew there products. They are very good. I also get a dealer price so thats hard to beat. Thats why I can offer my kits with B&C drivers at prices better than the customer can get them anywhere else.
 
I must admit i'm starting to get a bit lost with 'real cd' and 'waveguide'. Perhaps i'm trying to bite off more than I can chew. To be honest I just thought it would be a matter of picking a high efficiency woofer, Horn mid with flare and and a horn tweeter. Then designing a cabinet from there. I guess much more research is required.
 
warnsey said:
I must admit i'm starting to get a bit lost with 'real cd' and 'waveguide'. Perhaps i'm trying to bite off more than I can chew. To be honest I just thought it would be a matter of picking a high efficiency woofer, Horn mid with flare and and a horn tweeter. Then designing a cabinet from there. I guess much more research is required.
It's not much more difficult than cobbling together a system using 3 different direct radiators. Biggest difficulty is the midrange flare*; most of the Pro ones are pretty bad so I had to build my own. After all that work I realised that HE Pro 10"drivers work very well and I have no need to stuff around with flares.

Some worthwhile reading.
http://audioheritage.org/html/perspectives/drews-clues/drews-clues.htm
http://audioheritage.org/vbulletin/showthread.php?t=12126
http://audioheritage.org/vbulletin/showthread.php?t=12967
http://audioheritage.org/vbulletin/showthread.php?t=19493
http://audioheritage.org/vbulletin/showthread.php?t=12751
http://audioheritage.org/vbulletin/showthread.php?t=12390

* I use the term flare for all horns and WG's unless I am being specific about one or the other.
tinitus said:
I think its a shame they dont make "pro" drivers better suited fore home use
Few high quality Pro drivers are 'not' suited to home use. Biggest limitations are usually higher Fs in LF drivers (so use a dedicated sub) and the difficulty in making a 2 way, though Earl would argue that I would think.
 
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Joined 2005
Well, with sensitivity of a CD around 110db I dont see any use of high powerhandling
I suppose that with lower powerhandling the quality and bandwith could be improved

Woofers have mostly too high Fs and low Qts...and insane powerhandling...fore homeuse there is no need fore double spider and stiff surround

Many of the drivers are supposed to be used in arrays to match

I believe that if home use was the target many things could be improved

I wouldnt be surprised if cheaper semipro drivers would work better fore home use
 
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