Hi,
I stumbled across the B&C DCM50 in the search for a midrange compression driver. It seems like it has only been used by very few people, but the ones that have used it recommends it highly. It seems to fit well into a 200 Hz tractrix or similar round horn, but any inputs on using it in a Yuichi 290 Hz horn? I have not been able to find the exit angle of the driver to evaluate if it matches the rather narrow throat of the Yuichis.
Recommendations for other horns to fit the DCM50?
Thanks!
I stumbled across the B&C DCM50 in the search for a midrange compression driver. It seems like it has only been used by very few people, but the ones that have used it recommends it highly. It seems to fit well into a 200 Hz tractrix or similar round horn, but any inputs on using it in a Yuichi 290 Hz horn? I have not been able to find the exit angle of the driver to evaluate if it matches the rather narrow throat of the Yuichis.
Recommendations for other horns to fit the DCM50?
Thanks!
DCM-50 is a good mid compression driver. I've used it a couple of times on LA Scala and Klipschorn speakers with satisfactory results. But after all. You can cross it that low. 500hz 2nd order is a good start point. I like it a little bit more than BMS 4590. A good horn is fc260 Edgar style Tractrix horn. If you live in US you probably can acquire them from Greg Roberts/Volti Audio.
I used a 4590 with my A290 nearly 20ya. It was much better than the large Trax I had made and used before it. I only took that system apart as I moved to an apartment and it wouldn't fit.
The horn may have a 300Hz flare but it never sounded good with a less than 600 Hz LR4 from memory.
The horn may have a 300Hz flare but it never sounded good with a less than 600 Hz LR4 from memory.
Since the horn + adapter + terminus end correction is only a ~443 Hz acoustic axial length (~ 0.436 octave lower), kind of surprised even this high sounded good.
Lynn Olson said he will be using it with AH340 horns. Post 15,334 https://www.diyaudio.com/community/threads/beyond-the-ariel.100392/page-767
May I ask you about your experiences with the DCM50? Why did you eventually switch to other drivers? Among other questions, what did you like most and least about it?
Heard it last month in these speakers; the ES450 horn.
https://josephcrowe.com/products/3d-cad-files-horn-no-1994-es450-biradial-for-jbl-2446-2-throat
Amplifiers were the Triode Labs 45 tube mono blocks. In this review of that driver/horn combo at 25:01, Troy describes what he heard by adding that 6uf cap.
In the 10 or more recordings played I experienced more neutrality than warmth. ymmv.
Bappe used the DCM50 in a three way with a large JMLC horn, before going two-way with the JBL2450J Be.
8 and 16 ohm versions available. https://www.linkedin.com/in/bennettprescott
Attachments
I used it in Autotech tractrix 200 from 400-3000 Hz. Sounds endlessly effortless and warm. Best midrange compressions driver I have heard.
And yet it's only a 2" diaphragm. https://bcspeakers.com/en/products/hf-driver/archive/2/8/DCM50 Or might the masterful sound of its midrange be due to having a 2" rather than a 1.4" throat?
Indeed, note in the conclusion of this review where Troy Crowe seems to have discovered the exact converse with the B&C DCX464 https://bcspeakers.com/en/products/coaxial_hf/1.4/8/DCX464
https://josephcrowe.com/blogs/news/b-c-dcx-464-16-with-es-600-biradial-horn
1.4" throat provides wider off-axis coverage in the upper treble than a 2" throat.
But would that statement only apply to the DCX464 because it's a coaxial driver?
Otherwise, would that statement also apply to most compression drivers, such as these, both with 3" diaphragms?
https://www.usspeaker.com/radian 745neoBepb-1.htm ?
https://www.usspeaker.com/radian 760neoBepb-1.htm
And if that’s true then how to decide between those two drivers and horns to maximize full response coverage, and applied driver HF contour filtering?
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B&C DCM 50 is not a standard compression driver. It is more like a small fullrange driver (paper/composite) with small closed enclosure and a slot in front of the cone.
I presume fs and x-max is something completely else than a 2 inch exit CD.
My experience from Tractrix 200 with JBL 2446 confirms that.
I presume fs and x-max is something completely else than a 2 inch exit CD.
My experience from Tractrix 200 with JBL 2446 confirms that.
More about B&C DCM 50
GoodSoundClub - Romy the Cat's Audio Site - DCM50 and 1428
Romy,
To clear up a few things about the Kilimanjaro RCA1428 clones.
The B&C DCM50 is a modern, neodymium clone/copy of the RCA MI-1428B. It was designed and built by B&C in Italy after Bill Woods of AHhorns talked the CEO into it.
The DCM50 is not an exact copy of an RCA1428 obviously, with a different case, different diaphragm, different phase plug and a different motor but it's very close basically to the original design. The large center suspended paper diaphragm is the main reason it sounds so good.
It real does sound good. Bill Woods says the DCM50 on his 300 Hz AHhorn makes the most natural sound he's ever heard. That's a direct quote.
A few years back, I commissioned Von Langa to modify a pair of DCM50s to field coil operation for me. That is the genesis of the so-called A1428WVL.
That Wolf marketed them the way he did, has nothing to do with me, but I agree he should have mentioned they were modified B&C drivers. I notice he no longer markets them at all, perhaps B&C objected.
By the way I researched and provided the information on MI-1428s to Herr Von Langa back when we were planning the build.
As for f.c. voltage, my modified B&C DCM50s are fitted with 14V f.c. motors and work just fine with my inexpensive solid state PSs.
My drivers are on 12-sided conical 300 Hz AHhorns and they sound great - beautiful upper bass/lower midrange, very realistic sound overall.
The modded B&Cs replaced JBL 375s on 300 Hz tractrix horns. Compared to my 1428 clones the 375s sound tinny and artificial.
I am very very pleased with the way my 1428 clones sound. However, I would not be surprised if the unmodified neodymium magnet DCM50s sound just as good or even better.
Would be pleased to have you over Romy if you're ever on the West Coast and would like to check out the new horns and drivers.
Peace,
Kerry[/COLOR][/COLOR][/COLOR][/I]
GoodSoundClub - Romy the Cat's Audio Site - DCM50 and 1428
Romy,
To clear up a few things about the Kilimanjaro RCA1428 clones.
The B&C DCM50 is a modern, neodymium clone/copy of the RCA MI-1428B. It was designed and built by B&C in Italy after Bill Woods of AHhorns talked the CEO into it.
The DCM50 is not an exact copy of an RCA1428 obviously, with a different case, different diaphragm, different phase plug and a different motor but it's very close basically to the original design. The large center suspended paper diaphragm is the main reason it sounds so good.
It real does sound good. Bill Woods says the DCM50 on his 300 Hz AHhorn makes the most natural sound he's ever heard. That's a direct quote.
A few years back, I commissioned Von Langa to modify a pair of DCM50s to field coil operation for me. That is the genesis of the so-called A1428WVL.
That Wolf marketed them the way he did, has nothing to do with me, but I agree he should have mentioned they were modified B&C drivers. I notice he no longer markets them at all, perhaps B&C objected.
By the way I researched and provided the information on MI-1428s to Herr Von Langa back when we were planning the build.
As for f.c. voltage, my modified B&C DCM50s are fitted with 14V f.c. motors and work just fine with my inexpensive solid state PSs.
My drivers are on 12-sided conical 300 Hz AHhorns and they sound great - beautiful upper bass/lower midrange, very realistic sound overall.
The modded B&Cs replaced JBL 375s on 300 Hz tractrix horns. Compared to my 1428 clones the 375s sound tinny and artificial.
I am very very pleased with the way my 1428 clones sound. However, I would not be surprised if the unmodified neodymium magnet DCM50s sound just as good or even better.
Would be pleased to have you over Romy if you're ever on the West Coast and would like to check out the new horns and drivers.
Peace,
Kerry[/COLOR][/COLOR][/COLOR][/I]