That strongly depends on where you plan to cross them over. The differnces you are left with after fully equalizing them will be whatever is not minimum phase. This will obviously increase towards higher frequencies.
With the chosen driver/horn selection atop the above Altec midwoofers, I hope to accomplishSuperb reproduction of well mastered SACDs and high res downloads.
Least accentuation of the worst aspects of my less than pristine but treasured recordings, but without making them sound “dumbed down”.
Presumably, with hardware of this quality the first goal should not be at all difficult.
As for my “technically challenged” recordings, Pierre had very kindly agreed to evaluate them on his system (via my Google Drive and my Excel sheet playlist)-and with my request that he be ~ 87% merciless in his reviews. Of the 59 recordings (mostly CD track rips saved to uncompressed WAV files), most of those 1960s era tracks with less than great sound suffered from excessively applied compression, perhaps to ensure against signal overload of vinyl cutting lathes. And there were several that sounded “congested” (during busy orchestral or multi-vocal passages), presumably due to analog tape saturation and/or poor miking/baffling techniques.
Of course, even with Pierre’s skilled discernment, nothing about this rating process compares to actually being in the room. But according to Pierre: Yes some of your favorite tracks don't sound as good as others. It's not the speakers, it's baked into the track. This does not mean listening to them on high fidelity speakers is not enjoyable. Good systems do this: they tell you the truth. They also steer you through different music that sounds unpleasant on lesser systems. Your mind will bath in the beauty of some of your other tracks . Me, I find there is more gained than lost.
Sounds like a no-brainer to go with Pierre’s 16 ohm Radian BEs, yes? But the B&C DCM50 16 ohm is one driver that keeps me wondering. Everyone I’ve found who’s heard it raves about it, including Troy Crowe, as you will see below. Indeed, Lynn Olson’s acting on Troy’s suggestion to use it in his new speakers. https://www.diyaudio.com/community/threads/beyond-the-ariel.100392/page-767
And Profiguy’s #4 post speaks of a thrilling experience. https://www.diyaudio.com/community/threads/suitable-wg-xover-for-b-c-dcx50.387590/
In this video, Troy reviews his ES450 horn using three drivers, including the DCM50. Note from 5:54 to 6:32. Thereafter, while all other data are included, Troy unintentionally omitted the GedLee distortion plot for this driver. But at 17:15 thru to 25:01, after the addition of single cap, Troy’s comments on the DCM50’s performance-at least in the ES450 horn-go well above and beyond those of Profiguy’s.
https://josephcrowe.com/blogs/news/es-450-biradial-no-2143
Granted, such as system won’t have the HF extension of Pierre’s Radian BEs, at least not via a two way design,
which if I'm not mistaken usually provides more coherent and/or less colored sound quality.
But along with delivering superb detailed sound with tonality from high resolution sources
https://www.hdtracks.com/#/album/609d371c6e312b499e6498bb , based on Profiguy’s and Troy’s
commentaries, might the DCM50 be more likely to present my overcompressed recordings in a more pleasing way?
Comments? Suggestions?
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-you might also read through the subjective opinions here:
https://ultrahedonism.blogspot.com/2023/06/speaker-design-one.html
https://ultrahedonism.blogspot.com/2023/06/speaker-design-one.html
Don't know how to contact blogger. https://www.blogger.com/profile/00966208781747111885
Here’s the thread:
https://www.diyaudio.com/community/threads/extensive-driver-test-and-comparison.400875/
Why: specifically because he mentions the DCM50 in relation to other drivers. Subjective opinions that oltos was asking for. (..kind’a thought that was obvious.)
https://www.diyaudio.com/community/threads/extensive-driver-test-and-comparison.400875/
Why: specifically because he mentions the DCM50 in relation to other drivers. Subjective opinions that oltos was asking for. (..kind’a thought that was obvious.)
Apologies for such unscientific modes of driver evaluation, but if you read post # 2024 you'll probably realize how trying to ensure realization of my second goal inevitably involves subjective judgements. Indeed, even after completing his measurements, Troy Crowe often concludes his driver reviews with listening tests, and where he notes different aspects of the driver's sonic characteristics.
Oh it’s definitely (deeply) flawed, but some aspects of performance that he mentions don’t have much to do with freq. response.
I don't know about Troy, but if one is serious/honest about claims, do the listening/subjective test first. Objective stuff should come after. Influence of seeing anomalies in distortion or frequency response is disturbing judgement as well as sighted comparisons...
Like any of his reviews I've seen on youtube (exactly the same as the text versions on his website), I've never found where Troy's measurements on drivers impacted his subjective impressions, and vice versa.
No apologies required. I just find it surprising, in some of these cases the drivers have markedly different frequency response, on are different horns and it's all subjective from memory.
That means the on axis doesn't match and neither do the polars and probably the levels as well. Unless you are on the same horn, level matched and EQ'd to the same frequency response how valid could these comparison's be?
It is beyond obvious the listening test's of your finished system are paramount. I just don't see how constructive subjective impressions are under the above conditions from the internet.
YMMV
Rob
Yes. If you listen to different drivers on the same horn, with EQ taken care of, then they should sound significantly similar with the following exceptions.
You may see small differences where the driver wavefront is not properly established by the phase plug, or the angle is not right for the horn. In these cases you will get varying amounts of HOM. These have varying polar implications and are not fixable through EQ.
You may see small differences where the driver wavefront is not properly established by the phase plug, or the angle is not right for the horn. In these cases you will get varying amounts of HOM. These have varying polar implications and are not fixable through EQ.
it is hard to give recommendations based on this type of questions. What is interesting to consider is that you mainly have to deal with two separate parts of the working range of a driver.
One range is what we call the "horn theory range", where traditional horn theory works to describe the system. This is the low frequency part of the system (the low end of the compression driver and the horns working range). The maths of this part is not very complicated and it describes how the acoustic impedance of the horn interacts with the motor, diaphragm, compliance, compression etc to determine the sensitivity and general energy response at low frequencies.
The other end of the spectrum, and what a few people think is so unimportant for a compression driver that we should search for other threads to discuss it, is where the driver and horn no longer can be described with the "simple" horn equation. This is the part of the range where the horns properties as a waveguide starts to become really important. As frequency increases and wavelengts gets smaller, this type of property moves inwards in the system where the dimensions are smaller. Suddenly the phase plug in general, the exit part of the driver, the compression chamber (between the diaphragm and the phase plug) and even the small individual paths through the phase plug turns into waveguids in some way. This is when waveform shapes goes out of shape, multiple types of resonances occur, and we even get distortions that transitions out of the driver and gets multiplied by the horn. The scientific therm for this is higher order modes.
When you compare drivers, even if the drivers have many similarities, and even if the frequency response is close to identical, you will normally still get differences that are hard to find in measurements. Relatively small differences in the internal shape of the drivers parts will cause different audible results. So even if the drivers are similar and they are EQ-ed to the exact same response, you will often experience audible differences that are very hard to find in measurements. The most common way we see differences like this is when a driver seems to be just a lucky match with a horn, while a not too different driver just does not seem to work at all with the same horn.
I can't see how Troy describing, “over the internet”, what he actually measured and heard from a specific driver in a specific horn under specific conditions (e.g. adding a capacitor of a specific value) could not be very useful towards successful driver and/or horn selection. If not, what am I missing here?For example, earlier finding the DCM50 working “admirably” in his ES290 (but not in a client’s A290) horns, is largely how Troy made the final speaker configuration proposal to Lynn Olson https://www.diyaudio.com/community/threads/beyond-the-ariel.100392/page-767 Troy suggested the DCM50 and the AH340 horn for above Lynn's ~ 4 cu ft sealed Altec woofers.
Obviously, because Troy measures, (actively and/or passively) crosses and EQs and knows the geometry of the driver/horn combination, he can make any needed tweaks along the way, and then during the final listening sessions when the complete speaker
system is built.
Indeed, as Troy has my 3 cu ft sealed Altec midwoofers that Jim Salk had shipped to him last year,
the above process is also how I hope Troy might then decide on the best driver/horn pair for realizing my two objectives.
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Hello oltos
You are not missing anything we have different priorities and ways of doing things
As far as the comments:
Could be! Are you using the same horn/ CD combo? Is your FR target the same as his? Have you ever sat with him during one of his evaluations so you know what he means? When he hears depth is that what you hear?
When I DIY I don't pole for opinions. I see it as pointless. What sounds good to me could sound horrible to someone else and visa versa.
Don't put too much weight on what others think.
What matters are the choices you make and how well you integrate your drivers and crossovers into a complete system. This determines how it's is going to sound.
That's the bottom line and more importantly does it meet your personal goals. It's your goals not someone else's
You are not going to know until you build it.
Best of luck I hope what ever you decide you end up happy with!
That is what matters most.
Rob
People often (if not most of the time) use the opinion of others to help narrow-down a choice when the options are plentiful, be it a compression driver, car, restaurant, etc.
In this instance oltos just seems to be narrowing his focus on a few drivers to make a choice that would be more likely to appeal to his sonic priorities long-term (assuming he can get everything else close to “right”). Sure: he could well be at the point of ”analysis paralysis” - but it’s not a cheap purchase and it requires a lot of development (time-sink) after making the purchase: in other words that added time spent now comparing the responses of others might well save him both money and considerable time and effort later.
Unfortunately I can’t really add to his posed questions because I haven’t heard the drivers he is interested in, so the best I can do is provide a source that has (even if it’s not a rigorous comparison).
Moreover, this is absolutely all within this thread’s purpose: searching for that “best compression driver”.
In this instance oltos just seems to be narrowing his focus on a few drivers to make a choice that would be more likely to appeal to his sonic priorities long-term (assuming he can get everything else close to “right”). Sure: he could well be at the point of ”analysis paralysis” - but it’s not a cheap purchase and it requires a lot of development (time-sink) after making the purchase: in other words that added time spent now comparing the responses of others might well save him both money and considerable time and effort later.
Unfortunately I can’t really add to his posed questions because I haven’t heard the drivers he is interested in, so the best I can do is provide a source that has (even if it’s not a rigorous comparison).
Moreover, this is absolutely all within this thread’s purpose: searching for that “best compression driver”.