Need Help on BMS 4592ND MIDRANGE vs. BMS 4592ND dual diaphragm compression driver,

[hallcon83]

- Hello, I  need help please, Has anyone Heard Both the BMS 4592ND Midrange and the BMS 4592ND Coaxial drivers? .... My question is Does the Midrange sound the same for both of the drivers, or does the BMS 4592nd - Midrange sound better than the Midirange in the BMS 4592nd Coax unit, or are the Midrange's in both compression drivers exactly the same?

 

- Thank you! 

[OO1]

they are the same part  ------a Coaxial  neo magnet compression driver with a Midrange and a  tweeter in 1 assembly

http://www.bmsspeakers.com/fileadmin/bms-data/product_data_2011/compression_drivers_neodymium/bms_4592nd_2011-04_coaxial_neodymium_compression_driver.pdf

 

[hallcon83]

Hi Randy , thanks for your help, I appreciate it.

 

-  I'm hoping someone has heard both , I am concerned that the coaxial tweeter might affect the midrange performance...

- I have heard the BMS 4592nd- MIDRANGE and Really like it, but the coaxial would a better option but I am worried it might not sound as good.... as the midrange alone... 

[muel]

I have only heard the mid so this is hearsay... I have heard complaints about the  tweeter not meeting hopes or expectations.  I would have tried it myself but was scared away by others who tried although there was someone here that was still using it... sorry I don't remember who.

The BMS mid is wonderful though, isn't it?!   

Oh wait.. found the link with some info:  

 

[Chris A]

10 hours ago, muel said:

I have heard complaints about the  tweeter not meeting hopes or expectations.

After the BMS 4592ND is tri-amped and dialed in on a K-402 horn, I can't tell the difference between the TAD TD-4002s and the 4592ND.  Since the BMS 4592ND costs about 1/4 or less of the TADs.  I'd call that success.  Here are the DSP settings that I use currently:

 

https://community.klipsch.com/index.php?/topic/186238-bms-4592nd-coax-xo-sugestion/&tab=comments#comment-2416945

 

If you couple the BMS driver with a Hypex FusionAmp FA123 having a three-way DSP crossover with three NCore amplifiers including one for your bass bin, all you need do is provide one signal cable to the FA123 and a power cord at the loudspeaker. No other extra pieces of equipment are needed. Problem solved.

 

Chris

[hallcon83]

Hi guys - thanks , for all the help.

 

-  thank you Chris , I have a couple of questions, I was wondering - 

 

1. -  Do you think that the Hypex solution sounds as good as using a Xilica crossover? 

2. -  How do you feel about the K402 - MEH Horn vs  the Jubilee Horns  do you feel like one is better then the other?   

3. -  After some time how are feeling about the  the stacked AMT's  vs.  the K402- MEH  Horn , do prefer one over the other?

[Chris A]

1. Yes.  In fact, I'm currently sweet talking my wife to get one or three of them to replace at least the center K-402-MEH electronics, but I'd like to replace the Xilica and associated amplifiers for the front three (L, C, R), including my First Watt F3, which heats the room year round.  My Samoyed doesn't appreciate being hot all the time during the spring/summer/fall season (but he's still the sweetest and funniest dog I've ever shared my abode with).

 

I actually expect the sound quality to improve with the FusionAmp FA122, which are Hypex NCore 400 amplifiers on the Jubs, and the FA123 on the K-402-MEH running the dual diaphragm BMS 4592ND.  It would run about $1200 to buy all three (two FA122s and a FA123 to replace the Xilica, the First Watt F3, and the remaining Crown D75As I'm currently running).

 

2. The Jubilees are superb, I've found, with suitable compression drivers (I use TAD 4002s, but I'd also recommend BMS 4592NDs, tri-amping them with FA123 Hypex DSP/amplifiers) and a bit of shortening down of the K-402 assembly to move the centerline of the K-402 toward to the bass bin centerline to improve the midbass performance and phase response flatness.  I don't know any other loudspeakers that can really match them for everything (save the K-402-MEHs) including sound quality, soundstage size and stability, dynamics, subconscious involvement, and smoothness.  The K-402-MEH adds a little on the midbass smoothness and the Jubs have a bit more bass oomph for larger listening spaces (i.e., the bass bins are a bit more efficient than the MEHs, and therefore a little lower bass modulation distortion, but the two have essentially the same bass extension if dialed in properly).  But you can't touch the form factor of the MEH over the Jubs (1/3 the height), and the price is also less than 1/3 of the Jubilees (and I'm including BMS 4592NDs and a Hypex FA123 DSP/amplifier in my estimate). 

 

[A long-winded answer, for sure...but I think most people will make their choice based on factors other than sound quality differences (which are small indeed).  Most people having the "small loudspeaker syndrome",  those that have more demanding midbass smoothness/response needs, and/or perhaps wanting to hold the costs down would probably choose the MEH, while those with the urge to own Klipsch's real flagship loudspeaker and that have the room for them will probably go for Jubs. (I've recommended to Roy to combine an K-402-MEH and a Jubilee bass bin, but I've received no response.  A K-402-MEH/Jubilee bass bin combination would solve all the remaining performance weak points of the Jubilee, but this seems to upset the "Klipsch die-hard Jubilee" fan-base here).  I won them as an essential part of my setup, and presently have no plans to change them out.]

 

3. I never got my stacked AMT-1s together, so I can't answer your question.  The president of ESS (Ricky Caudillo) verbally promised to send me a replacement diaphragm for my infant mortality failure diaphragm that I received in January, but then his company didn't do it.  I'm not buying AMT-1s any more since ESS apparently isn't standing behind their product, I'm sorry to say.  You can talk to @Rudy81  for his impressions in his double-stacked arrays. 

 

If I were to go with a stacked AMT-1 (and I wouldn't presently), I'd probably go with a three-high stack and use a Hypex FA123 on top to create a virtual "shaded line array" using the delay of the three DSP/amplifiers of an FA123 to approximate a physical shaded line array like option "f" in the figure below, which would address the vertical polar coverage issue of stacked AMT-1s.  This would require an additional DSP crossover for the bass bin (a quad-amped two way design):

 

 

In terms of the stacked/winged AMT-1s...they're not really in the same ballpark as the K-402-MEH due to the difference in midrange/midbass performance of the K-402 horn profile itself.  But I think the single AMT-1s on top of Belle bass bins work extremely well as surround channel loudspeakers in my present setup.

 

Chris

[hallcon83]

-   Hi Chris , thank you for your answers to my questions - I don't mind the long explanations - they are very helpful!

 

-  I have to go and do some reading I don't know much about what a "shaded line array" is - lol

 

-  I think the Hypex solutions are very interesting and may try it down the road...   but I may still try and find a Xilica , my situation is a little different from yours,  our surround sound system is in our master bedroom and it needs to be very compact so no room for MEH horns there.  I would be using them in main stereo which is in our living room and so I will only have the single pair of speakers to worry about.  Also I really was wanting to run my Horn Midrange and Tweeter using Tube Amplifiers.... with the option of trying out several different diy amplifiers that I want to build too , So I will probably be looking for  a new or used Xilica - whichever I can Find.

[The Dude]

I really like the idea of running 3 of the FA123's and 3 of the BMS Dual diagram 4592ND.   This could eliminate some rack space in the front of the rack.  Looks like the tri combo could set one back around 3k in gear.    

[babadono]

On 11/15/2020 at 10:22 AM, hallcon83 said:

Hi Randy , thanks for your help, I appreciate it.

 

-  I'm hoping someone has heard both , I am concerned that the coaxial tweeter might affect the midrange performance...

- I have heard the BMS 4592nd- MIDRANGE and Really like it, but the coaxial would a better option but I am worried it might not sound as good.... as the midrange alone... 

I've heard both on the big Eliptrac horn made by GotHover(FastLane Audio) back in the day. I did not like the coax unit, the high freqs beamed terribly. Could have just been the horn. I went to just the midrange driver and a separate tweeter and tweeter horn. The midrange is very good and LOUD, I stepped it down like 13dB IIRC.

[hallcon83]

Quote

8 minutes ago, babadono said:

I've heard both on the big Eliptrac horn made by GotHover(FastLane Audio) back in the day. I did not like the coax unit, the high freqs beamed terribly. Could have just been the horn. I went to just the midrange driver and a separate tweeter and tweeter horn. The midrange is very good and LOUD, I stepped it down like 13dB IIRC.

- 

-  Last year I got to spend two days at the Lone Star Audio Fest listening to the 4592ND - Midrange in the Volti  Audio Vittora Horn Speaker and I agree that is a Great sounding driver!  So I sold my main speakers and my VTL 350 watt Monoblock Amplifiers and I am getting ready to maybe incorporate it into a horn speaker of some kind , my top choices are a upscaled La Scala, or maybe something like the Tune Audio Anima Horn speaker design.... but Chris's MEH Horn looks like the most interesting option!  But I wanted to make sure that the 4592nd Coax sounded as good as the 4592nd - midrange does....... I have read several places that other people felt like you did ,  that they didn't like the Tweeter in the Coax , but maybe it's how it's implemented , maybe the K-402 Horn or the crossover / PEQ filter that Chris is using or both together make the tweeter sound better ---  

 

[babadono]

3 hours ago, hallcon83 said:

but maybe it's how it's implemented , maybe the K-402 Horn or the crossover / PEQ filter that Chris is using or both together make the tweeter sound better 

Agreed---i did not spend a lot of time on it. i did not have digital crossover at that time, just ALK ES passive crossovers. But with the separate tweeter they sound good.

[Chris A]

5 hours ago, hallcon83 said:

I have read several places that other people felt like you did ,  that they didn't like the Tweeter in the Coax , but maybe it's how it's implemented , maybe the K-402 Horn or the crossover / PEQ filter that Chris is using or both together make the tweeter sound better ---  

Apparently those that complain about the BMS 4592ND is listening to the driver mono-amped with the passive crossover that BMS sells for it.  That's the problem.  The driver needs to be bi-amped and each channel EQed and time-aligned carefully (using the link I posted above for the K-402 horn). It took a little effort to find those settings, but they work.

 

Chris

[hallcon83]

On 11/23/2020 at 8:01 PM, Chris A said:

Apparently those that complain about the BMS 4592ND is listening to the driver mono-amped with the passive crossover that BMS sells for it.  That's the problem.  The driver needs to be bi-amped and each channel EQed and time-aligned carefully (using the link I posted above for the K-402 horn). It took a little effort to find those settings, but they work.

 

Chris

-  Hi Chris , I am really looking forward to building the K-402 MEH Horns!! .....  I am planning on calling Xilica in the next day or two to ask about the firmware upgrades and get their opinion on the used unit. 
-  Also I was looking back over a couple of your threads searching for some info , I thought it was in your thread where you introduced your MEH Horn concept... but I somehow missed where you recommended the best place to purchase the BMS 4592nd-Coax Drivers from??  - Thank you, Dean

[Chris A]

I bought my BMS4592ND from Thomann US.  Right now the Euro-to-USD exchange rate isn't terribly good (the price of the driver has risen about 15% since I bought mine two years ago, due mainly to currency exchange rates.  I bought mine for right around $461 USD two years ago.  Perhaps the currency exchange rate will swing back after late January (if you catch my drift).  In any case, I don't think you should buy the drivers first, but put it off until you start to integrate everything. 

 

Thomann shipped from Germany to the US and it was at my doorstep three business days later (again, now the US Cusstoms import delays are so affected by politics presently, my guess is that it will take over a month for you to receive them).  [I know that my heartworm medication from Canada (actually shipped from New Zealand) is presently taking 4 1/2 weeks on average.  This isn't the fault of the manufacturers, sellers or shippers, but the US Gov't.]  I'd like to see a little less politics involved in international sales for a change. 

 

Chris

[Marvel]

4 hours ago, Chris A said:

This isn't the fault of the manufacturers, sellers or shippers, but the US Gov't.]  I'd like to see a little less politics involved in international sales for a change. 

 

Some of that is the carriers, although many have added more cargo only flights, where a lot of cargo was travelling on the passenger flights.

[Honeybadger]

Never hear a Coaxial I really enjoyed, but apparently just not hear the right set up yet.

 

H.B. 

[Chris A]

22 hours ago, Marvel said:

 

Some of that is the carriers, although many have added more cargo only flights, where a lot of cargo was travelling on the passenger flights.

 

In the cases I've had, the tracking information shows the packages getting to California within 2-3 working days...then it goes black (i.e., I guess that the carriers can't call US Customs out on the delays, or they'll get punished even more). 

 

9 hours ago, Honeybadger said:

Never heard a Coaxial I really enjoyed, but apparently just not hear the right set up yet.

This is a good place to lay out the following about this maligned topic of dual-diaphragm compression drivers, and avoid some notable memeplexes (information that isn't correct and was not actually achieved by first-hand learning) that audiophiles like to perpetuate in this pastime.  These type of drivers outperform anything else for home hi-fi duty except perhaps TAD beryllium diaphragm compression drivers--because of their unique design that avoids having to use two separate horns to do one job.

 

This isn't a cone/cone or cone/compression driver co-axial.  It's a dual diaphragm ring-radiator compression driver--with two separate electrical circuits, including four connectors on the back of the driver. Please refer to the diagram below for a cross section view of this driver to understand its configuration: red = tweeter diaphragm, green = midrange diaphragm, yellow = compression chamber...

 

 

1. This driver doesn't suffer from high frequency chatter that you hear with dome-type titanium or aluminum compression drivers (listening to very clean ride cymbals in jazz and other music genres) due to the elimination of the center dome structure of the diaphragms, which makes the diaphragms effectively much structure stiffer and lighter. 
    
2. You'll also note that the tweeter diaphragm here is a little closer to the center phase plug (the spike-looking object in the middle) than the midrange diaphragm.  In the BMS 4592ND, the tweeter diaphragm leads the midrange diaphragm in time by a small amount that's equal to one wavelength at the crossover frequency (nominally 6 kHz). 
    
3. If you bi-amp this driver and EQ the response of each diaphragm to be flat in SPL vs. frequency, and correct the time alignment of the diaphragms to be coincident at the phase plug then you end up with a full-range driver (nominally 375 Hz to 21 kHz) like the TAD TD-4002 or 4001, but without the cost of the beryllium dome diaphragm, and with no concerns about potential toxicity of beryllium. (Note: no one I know would ever use the TADs in a home environment in such a way that would cause the beryllium diaphragm to hit its stops, so there is no real hazard probability with the TADs.)
    
4. Additionally, the polyester dual diaphragm BMS 4592ND diaphragms have the geometries of ring radiators that precludes diaphragm chatter.  The need for extreme stiffness of the diaphragms is eliminated, and the need for the extremely lightweight+stiff beryllium material is thus avoided.  Additionally, the diaphragm material itself and its geometry have much better self-damping properties than a single done-shaped diaphragm of the TADs. 
    
5. One additional point to be made: the dual diaphragm driver breaks the frequency spectrum into two portions: ~375 to ~6000 Hz, and ~6000 to ~21000 Hz.  So the FM distortion sidebands are much lower than using a single diaphragm to cover that frequency range.  This means that you get extremely clean output even at very high output levels. And each diaphragm design can be better optimized to produce more effective and cleaner output for the each of the midrange and tweeter frequencies than a single diaphragm can be designed to handle.
    
6. The BMS 4592ND also uses neodymium permanent magnets--which is much lighter overall than ferrite because it is more able to concentrate their magnetic fields at the correct locations around the voice coils, with their geometry optimized for a more effective voice coil field strength than a typical dome-type diaphragm compression driver.
    
7. I do not recommend either version of the driver (the one-diaphragm 4592-MID, or the two diaphragm 4592ND) if you do not use acoustic measurements (I strongly recommend REW or even something more powerful--but not "room correction software") to guide your EQ that is required for either of these two drivers on whatever horn that you choose to fit to them.  I strongly recommend using DSP crossover for that purpose, either driver version. 
   
   To not use a DSP crossover with these drivers and whatever horn you choose would be very much like the old days of mechanical breaker points on engine distributors.  You can just plop in a new distributor or replace the points in the engine and it might work, but usually not very well.  If instead you use a timing light, then you can dial it in properly (i.e., rotate the distributor housing proper point) and get proper engine performance.  These drivers similarly require dialing them in--in order to get the proper performance out of them.  If you do not do this, the driver/horn timbre will be off, and the sound of the driver will be oddly irritating in the higher registers and missing other frequencies in its high frequency response.  If you need help to measure and use a DSP crossover to dial in your BMS 4592ND (or any other drivers/horns), PM me for measurement and DSP dial-in support.

_________________________________________________

 

One of the things that find curious is that many people accept three-way designs having separate midrange and tweeter drivers and horns.  The effects of having those two separate horns and drivers/horns is actually pretty high from an acoustics perspective.  The two separate drivers/horns, due to their size and shape, create interference (lobing polar output and cancellations off-axis) between the two outputs because the two sources are separated vertically by much more than a quarter wavelength at the crossover frequency--a distance of about 5/8" at 6 kHz.  This small distance is impossible to achieve using two separate drivers and horns at that crossover frequency.

 

My advice is use dual-diagram or concentric drivers if you are trying to cross to a higher frequency driver above 1000 Hz or higher...because you can't get two separate drivers and horns close enough together to avoid polar coverage problems in their in-room output--without causing other more severe issues in the polar output of the drivers.  Usually it's vertical axis lobing that's the issue.

 

Chris

[hallcon83]

" I bought my BMS4592ND from Thomann US.  Right now the Euro-to-USD exchange rate isn't terribly good (the price of the driver has risen about 15% since I bought mine two years ago, due mainly to currency exchange rates.  I bought mine for right around $461 USD two years ago.  Perhaps the currency exchange rate will swing back after late January (if you catch my drift).  In any case, I don't think you should buy the drivers first, but put it off until you start to integrate everything."

-----------------------------------------------------------------------------------

 

Hi Chris, I was wondering why the exchange rate might go down.... I would think that we would soon be in a weaker economic position because of the uncertainty , due to the new folks coming in having said they want to have new mandatory covid lockdown and so many businesses have to close down again.... as well as the promise to severely restrict oil and gas production in favor of more green energy options.........  --  just curious your take on the business climate...  thank you ,

[Chris A]

It seems apparent that when all the present uncertainty settles out, the dollar will strengthen vs. the Euro.  As the vaccines roll out in the US, I think the USD will strengthen even more, which is the major source of the dollar dropping (i.e., "COVID" business shutdowns) apparently disproportionately relative to other country economies.  I think the USD has been artificially depressed since ~4 November or slightly before. Additionally, I don't believe that the Euro can remain strong as Brexit becomes a reality in a month or so--it's a downside for the EU as much as the UK, and stronger US/UK economic ties might also tend to actually strengthen their currencies from current positions vs. the Euro.  It seems that all the downside in the USD and GBP might already have been realized with the drop in their valuations in the past 6 months.

 

Chris