For you horn guys: What kind of compression driver are you using for high frequencies? Why that choice (if you know...)

morricab

Well-Known Member
Apr 25, 2014
3,138
375
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Switzerland
#21
Am also currently dressed in the BMS polyester, just a really nice treble even compared to the Maggie 20.7s. Just sounds completely right to me and I did consider getting in the Fostex T-500 also.

Might still explore a second mid with separate tweeter for the Pap horn as a second option as the Pap is modular and allows for reconfiguration... a bit like DIY but with a stream of options. Am also considering the Autotech Iwata horn for the mid and tweeter.

That said I’m really enjoying the BMS and it’s making upgrading a bit of a hard choice as it does just work so beautifully in the Pap horn... I also have an upgraded cap with duelund bypass cap and path resistors on the way for the BMS compression horn so will be very interested to see where that takes it.
You could try the following 1.4" drivers: Beyma CP755Ti or Nd, Radian 745pb or 951Neo. I think most of these are lower in sensitivity than the BMS so a crossover adjustment would be required to match the level correctly. Not saying you should but perhaps as an experiment...
 

Audiophile Bill

Well-Known Member
Mar 23, 2015
2,244
641
113
UK
#22
The only hesitation I have is that so far, I haven't heard a high frequency driver that used mylar or polyimide or whatever plastic, that I really loved. The ones I have heard so far (by no means exahaustive) are slightly more "tizzy" and seem not to differentiate subtle tonal and textural differences in high percsussion than good metal diaphragm'd designs. Also, where distortion measurements are available, they seem to be a good deal higher in 2nd and 3rd harmonic distortion...of course output level matched this might disappear (118db down to normal listening levels probably means vanishing low distortion for example).

Like I said, I am thinking about taking the plunge on this BMS/horn combination given that it is kind of a turnkey solution...making a true high end DIY straight forward...
If you visit UK, pop in for a listen.
 

the sound of Tao

Well-Known Member
Jul 18, 2014
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#23
The BMS is for me the antithesis of tizzy Brad.

It’s really quite a gracious treble, not overplayed or imposing. I suppose everything is a compromise but this is for me a musically right compromise. I might explore a bit more about reinforcing the bottom end with my horns but being careful to not also overstretch from the midcentre as I figure balance is about making the roll off at both ends not too concentric.

I have all these ideas about reinventing what I have but the BMS just keeps making me want to sit and listen to what I have and the music. It has a prepossessing kind of core and it is modest. Essentially it is doing it all with just the help of a couple of 15 inch woofers either side.

PS the hulking big Mundorf EVO supreme Oil caps and the duelund silver bypass caps and path audio resistors have arrived today so will be cap and resistor rolling into the horn xover over the weekend :)
 
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kodomo

Active Member
Apr 26, 2017
333
249
43
#24
I have 5 way system, that was the best for me after a lot trials. I had bms 4592nd-mid as well for covering wider bandwidth, TAD drivers in their horns and several others before. Here are the horn loaded 4 channels;
120-500hz a modified 12" supravox 285-2000
500-5khz - Radian 850
5khz-9khz - Radian 475be
9khz-20khz - Fostex t500amkII
 

morricab

Well-Known Member
Apr 25, 2014
3,138
375
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Switzerland
#26
I have 5 way system, that was the best for me after a lot trials. I had bms 4592nd-mid as well for covering wider bandwidth, TAD drivers in their horns and several others before. Here are the horn loaded 4 channels;
120-500hz a modified 12" supravox 285-2000
500-5khz - Radian 850
5khz-9khz - Radian 475be
9khz-20khz - Fostex t500amkII
Ah, I see. I thought you had a 4-way system. Didn't realize you had ANOTHER Radian driver covering a lower range. Very cool. Seems you think the Radian drivers are the way to go...at least for sane money. you have it all stitched together actively or passively?
 

kodomo

Active Member
Apr 26, 2017
333
249
43
#27
Ah, I see. I thought you had a 4-way system. Didn't realize you had ANOTHER Radian driver covering a lower range. Very cool. Seems you think the Radian drivers are the way to go...at least for sane money. you have it all stitched together actively or passively?
Passively. I have tried various drivers, these were my choices and it is not based on cost. Frankly I haven't tried ale as it was not possible to get my hands on them, same goes for goto. However, a week ago I had the chance to listem to a goto sg6tt tweeter and I still prefer the fostex t500amkII
 
Likes: christoph

morricab

Well-Known Member
Apr 25, 2014
3,138
375
83
Switzerland
#28
Passively. I have tried various drivers, these were my choices and it is not based on cost. Frankly I haven't tried ale as it was not possible to get my hands on them, same goes for goto. However, a week ago I had the chance to listem to a goto sg6tt tweeter and I still prefer the fostex t500amkII
Very interesting. How close do you think the non-Be version of the 475 is to the Be version? I noticed that you use the non-Be 850...any reason why?
 
Likes: jeffrey_t
Jan 29, 2012
1,190
315
83
#29
I have 5 way system, that was the best for me after a lot trials. I had bms 4592nd-mid as well for covering wider bandwidth, TAD drivers in their horns and several others before. Here are the horn loaded 4 channels;
120-500hz a modified 12" supravox 285-2000
500-5khz - Radian 850
5khz-9khz - Radian 475be
9khz-20khz - Fostex t500amkII
You have an excellent system! I have a few questions: Are you saying that you preferred the Radian drivers to the TAD drivers you tried in your horns? Who made your spherical horns?
 
Likes: morricab

kodomo

Active Member
Apr 26, 2017
333
249
43
#30
You have an excellent system! I have a few questions: Are you saying that you preferred the Radian drivers to the TAD drivers you tried in your horns? Who made your spherical horns?
I preferred Radian 850 to TAD 4001 in my setup. TAD 2001 was marginally better than 475be but again with my setup, Radians worked better together. If I did not have the fostex to cover everything over 9khz, I may still have chosen the TAD 2001
 
Likes: jeffrey_t
Jan 29, 2012
1,190
315
83
#31
I preferred Radian 850 to TAD 4001 in my setup. TAD 2001 was marginally better than 475be but again with my setup, Radians worked better together. If I did not have the fostex to cover everything over 9khz, I may still have chosen the TAD 2001
Did you try the BE diaphragm in the 850? Also, may i ask who made the horn enclosures?
 

the sound of Tao

Well-Known Member
Jul 18, 2014
1,172
628
113
#33
The BMS is for me the antithesis of tizzy Brad.

It’s really quite a gracious treble, not overplayed or imposing. I suppose everything is a compromise but this is for me a musically right compromise. I might explore a bit more about reinforcing the bottom end with my horns but being careful to not also overstretch from the midcentre as I figure balance is about making the roll off at both ends not too concentric.

I have all these ideas about reinventing what I have but the BMS just keeps making me want to sit and listen to what I have and the music. It has a prepossessing kind of core and it is modest. Essentially it is doing it all with just the help of a couple of 15 inch woofers either side.

PS the hulking big Mundorf EVO supreme Oil caps and the duelund silver bypass caps and path audio resistors have arrived today so will be cap and resistor rolling into the horn xover over the weekend :)
Pap horn xover upgrade part 1.

That’s not a capacitor... now tthissss is a capacitor... D521E78F-D89E-427D-94D8-5E148DABF7EE.jpeg

Just doing it step by step but even just swapping out the stock white 33 uF capacitor to the Mundorf Supreme Evo Oil for the BMS horn has been in itself quite a staggeringly good move.

Significant improvements even straight up in terms of overall balance, naturalness, dynamics and flow. Feels like I just went in and did a very solid (and costly) upgrade on my front end.

The top end was very, very good, now it’s really exceptional and starting to even step out in front of the pack even up against the Maggies and the Harbeths. Drum kits have even more midbass kick and authority, still not quite as much slam as the Harbeth 40.2s but a very real sense of... well realness... changing in the resistors on the woofers should be an interesting experiment. Horns on this are incisive and amazing and piano is just absolutely magic.

Playing Jamie Saft at the moment after some Rachmaninov and both these genres are fabulously well served and even more compelling after this relatively modest upgrade.

I have yet to add in the parallel Duelund silver bypass caps or swap in the path audio resistors but already I am very much feelin the love in this xover upgrade. This horn has truly exceptional potential.
 
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Duke LeJeune

[Industry Expert]/Member Sponsor
Jul 22, 2013
189
72
28
Princeton, Texas
#34
Something I have found to make an audible difference is, getting a good match between the exit angle of the compression driver and the entry angle of the horn. A mis-match there introduces diffraction, and diffraction can degrade sound quality and impart a edginess the becomes progressively more audible as the SPL increases. Unfortunately few manufacturers publish entry and exit angles for their horns and compression drivers, and some will even accuse you of industrial espionage if you have the audacity to ask them.

I was involved in a project that included controlled blind listening comparison of a well-respected $1k ballpark compression driver vs a $100 ballpark compression driver. They were mounted to identical horns and had identical woofer sections, and the crossover for each was optimized. The horn's entry angle was a good match for the $100 driver's exit angle, but not a good match for the $1k driver's exit angle.

The $100 driver was preferred by the panel of listeners in the controlled blind test. The only conceivable advantage of the $100 driver was in the matching of exit angle and entry angle. The $1k driver had everything else going for it.

So imo it's a little more complicated than "what kind of compression driver". Good synergy is a critical piece of the puzzle.
 

gian60

Well-Known Member
Apr 17, 2016
1,539
316
83
#35
The best horn tweeter i listen in my life is the ALE i had with my Audiotekne 8716 Cb
Was the ALE DEP,23 kg of weight

and the best super tweeter is a TAD 703 modified from Be Yamamura,really incredible,you can see on my old Sentry III
 

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gian60

Well-Known Member
Apr 17, 2016
1,539
316
83
#38
It was a special edition Yamamura did with ALE
Magnet in Permendure and membrane in beryllium

Below you see the tweeter ALE DEP that is 23 kg and on the mid,mid bass,mid high and tweeter,4550 and 1750 DEP super of more than 100 kg each

THIS IS REALLY INCREDIBLE

I follow this system of my friend together with Yamamura in 10 years development
 

Attachments

the sound of Tao

Well-Known Member
Jul 18, 2014
1,172
628
113
#39
Pap horn xover upgrade part 1.

That’s not a capacitor... now tthissss is a capacitor... View attachment 49917

Just doing it step by step but even just swapping out the stock white 33 uF capacitor to the Mundorf Supreme Evo Oil for the BMS horn has been in itself quite a staggeringly good move.

Significant improvements even straight up in terms of overall balance, naturalness, dynamics and flow. Feels like I just went in and did a very solid (and costly) upgrade on my front end.

The top end was very, very good, now it’s really exceptional and starting to even step out in front of the pack even up against the Maggies and the Harbeths. Drum kits have even more midbass kick and authority, still not quite as much slam as the Harbeth 40.2s but a very real sense of... well realness... changing in the resistors on the woofers should be an interesting experiment. Horns on this are incisive and amazing and piano is just absolutely magic.

Playing Jamie Saft at the moment after some Rachmaninov and both these genres are fabulously well served and even more compelling after this relatively modest upgrade.

I have yet to add in the parallel Duelund silver bypass caps or swap in the path audio resistors but already I am very much feelin the love in this xover upgrade. This horn has truly exceptional potential.
Pap horn crossover upgrade part 2 cont’d.

After just over a month (probably 3 weeks with the Pap horns in and the other fortnight with the big red Harbeths in rotation) the first cap upgrade in the crossovers has shaped up beautifully. The last few days the benefits went even past the essential sonic improvements and got into a new level of natural nuance and an added even more unmissable musicality in mids and up top. Really started to turn into something I’ve not really experienced before, a quicksilver and more clear liquidity that has stepped even further beyond senses of confinements from electro mechanical process... even more than I thought was possible.

Given how long caps can traditionally take to settle in and form up I think there’s possibly more improvement left in part 1 of the horn crossover upgrade.

So I figure nows the time for upgrade part 2 (or perhaps path 2) and have just put in the two lovely copper shielded pathaudio resistors into the R2 position in the pap crossover.

Just playing the first album now and at the risk of sounding like I’m over the moon well, I’m well fairly well and truly beyond that moon. The first notes were accompanied by some wide eyed expressions and a muttering of some joyous obscenities of genuine surprise.

Just sounding smooooth and effortless, the bass just got a nice extra bit of much useful added tautness AND fullness. Much appreciated especially for the pap horn after always having the bass happy harbys as it’s system sound comparison. Bass is more dynamic already. Drums are just sounding more incisive and with an even more realistic punch and timbre. It’s like they’ve just learnt some bass tricks from the Harbys and just stepped a little closer in that area. That is a great outcome for the OB horns.

There’s also just a bit of lowered noise floor that I really wasn’t expecting. The midbass got just a bit of tuneful extra shove in it as well but certainly not forced, just a might more attack or confidence maybe... but smooooth. Balance is a bit more bottom up now (perfecto) but this is just after the resistor install and some 20 minutes play time so think there’ll very reasonably be further improvement ahead.

The R2 resistor had the very cheapest and lowest spec’d part in the entire crossover in it, a plain Jane stock base mundorf resistor so its now got one of the best resistors available in for the job. Think the Pathaudios were about $30 USD a piece from memory so very much a real no brainer improvement already.

Still have the Duelund cast silver bypass caps to go in but I might wait till the Mundorf Evo supremes are well and truly settled. Exciting times ahead :)

Thinking some Elrogs and Acmes are next in line as a lift for the LM SET now that I’ve sorted through the speaker upgrades for the Pap trio horn.
 
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Sablon Audio

Industry Expert, VIP Donor
May 22, 2015
550
117
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#40
Good work Tao, it’s always pleasing to see people’s diy efforts being rewarded so handsomely! Although the Duelund bypasses should give you a nice uptick here, will the leads be sufficiently long to reach around those large evo caps?!? Could always open up the LM and use them to bypass the coupling caps in there.
 

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