Hmm.
I agree that the room is worth considering. I also know (just making a point here) that it's possible to succeed without much treatment of a (typical) room, instead putting all the responsibility on the speaker. You might be giving up the luxury of being able to get away with a regular box 😉
So I don't want to be drawing parallels between the spinorama power evaluations of commercial speakers, and the proper use of polar measurements during design.
Faital Pro 10PR410 shouldl do 200-2000 quite nicely
https://faitalpro.com/en/products/LF_Loudspeakers/product_details/index.php?id=101040120
https://faitalpro.com/en/products/LF_Loudspeakers/product_details/index.php?id=101040120
Troels has become an influencer for the various brands whose sales he is paid to increase.
Most of what macka quoted from TG is just the same marketing waffle that the manufacturers would have us believe - magic signatures of the components involved, we can't measure all that we can hear - all the same obfuscation, FOMO, and other nice inventions of the PR industry. Now insidiously coming not through glossy adverts, but from a folksy figure with some gravitas. It's still mostly rubbish.
Decent off axis response is important not despite of the room but because of it.
Most of what macka quoted from TG is just the same marketing waffle that the manufacturers would have us believe - magic signatures of the components involved, we can't measure all that we can hear - all the same obfuscation, FOMO, and other nice inventions of the PR industry. Now insidiously coming not through glossy adverts, but from a folksy figure with some gravitas. It's still mostly rubbish.
Decent off axis response is important not despite of the room but because of it.
Does REW show what is right and what is wrong?😀 I mean, what does it mean perceptually when ratio of direct and indirect sound changes? This is the core issue with all this DIY speaker stuff, because forums and books do not come with audio perception like it happens when one personally listens setup at home so it's very hard to connect written concepts to perception, and vice versa. Written concepts are usually perfectly understandable, like what you say there, but without personal experience (experimentation) it is very hard to really relate and connect how it sounds to me at a particular context at home. Context in general is seldom transferred over the forum threads, usually only after someone asks for it.
So, I think this is just listening skill stuff. Basically one has to experiment with this stuff and listen what works and what doesn't, how things change as one moves around eyes closed. I mean, there is distinct difference with sound with the critical distance ( I'm not sure if it's the technical critical distance, could be, but could be bit further away from speakers, see LLD by Griesinger ) where perception changes, as local room sound seems to suppress and phantom sounds get the focus from auditory system. I tried to measure with REW from both sides of this transition where it audibly happens with my system, but both are so close compared to each other that I cannot see anything obvious, any "threshold" there that would indicate what perception of sound is. Perhaps there is if enough data from various systems, but currently even if I see the data and hear how it sounds it's not obvious how they relate.
Luckily REW is not needed to find the distance where perception changes, only some listening skill to be able to detect there is a change, and then utilize that at will, listen either side as pleased. Basically this is the core of system positioning, how speakers and listener relate to each other and the room. Best thing doing it perceptually is that there is no need for any technical details or any details for that matter, no frequencies, no delays to early reflections, no details of speakers, just eyes closed and using ears find best positioning and listening spot to liking utilizing the transition to do AB testing live in real time and adjust until happy. What enables this is to be able to perceive when auditory system switches state, listening skill, and it's not too hard to notice first time, and after one does it's easy afterwards. Utilizing the transition one can start to reason that if the sound is not correct, what with the speakers (or with the room) would need to be changed in order to better.
I think this is core of circle of confusion in general, and I do not think it's well known that our own auditory system can provide two very different perception to stereo sound, two states in auditory system, which basically depend on listening distance (stereo triangle size). I'm glad to see you wrote about it. Listen too far and it's different sound, listen close enough it's another, both could benefit from different kinds of optimizations in the system. At point when one realizes some recordings sound better further away and some closer, and that sometimes one want's to be very involved in sound (closer) and sometimes more relaxed (further) it becomes obvious that a system need to be optimized for both (perceptual sounds) and that people behind the recording were subject to the same issues, listening distance, and whether they understood it's meaning or not they might have optimized the sound for either or both. Bam, confusion gone, and one can just move a little to always listen which ever sound feels optimal at that time.
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Yes exactly! And a bad speaker in a good room is still a bad speaker.
WRT audibility of different crossover components? Even if there are they will be subtle and won't make of break a good design.
Same thing with materials subtle if audible at all. Proper design is the most important hurtle.
Rob 🙂
We are all entitled to our own opinions.
This is the thing. In reading the full page to the very bottom you get the whole story.
https://hificompass.com/en/reviews/bliesma-m74a-6-m74b-6-m74p-6-and-m74s-6
A skilled transducer engineer knows this and so do his end users and his OEM pro loudspeaker manufacturers.
I actually had the same conversation with the B&C and 18Sound sales engineers. They said some of their OEM manufacturers specifically requested certain sonic characteristic that appealed to concert goers.
So l think that closes the loop on that aspect of driver engineering.
A bad loudspeaker is often not a bad design. Just the implementation cheated by bean counters with cheap compromised drivers.
This is where manufacturers like ATC and Volt have the crème of studio business. Their drivers have proprietary diaphragms and they are superbly manufactured. You really can hear the difference. But if you can’t no body cares.
Hello Ian
Call me confused but a key to designing a speaker is driver selection. If you choose to use cheap drivers with audible break-up modes and other issues your are going to end up with a "bad" speaker. Choosing them as part of your build is obviously a bad design choice.
I get you WRT commercial speakers but we are not within those constraints. If you have to wait a month to budget in the midranges you want you can do that.
I have Sean Olives how JBL does it somewhere have to post it. Your right they are given a budget, they look around to see if existing drivers will do and engineering does the best they can within that budget.
WRT materials it's all about implementation.
I have run comparisons between Aquaplas Coated Ti vs Uncoated, Coated Aluminum vs Coated Be. Level matched and they were different but not enough to make or break a speaker design.
That's the point if you want to try boutique caps go for it but don't expect night and day.
I have seen so many people endlessly chasing there tails going down the rabbit hole. It's a recipe for frustration and failure.
Maybe we should take what manufacturing engineers do as a lesson by making the best we can out of what we have.
In the very least you will learn how to complete a project and use that as a basis for what we can do better next time.
Rob 🙂
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I'm a noob to DIY audio, but wouldn't one of the major advantages to DIY be the ability to use iterative design to tailor your speakers to your preferences and room?
Just my recent experience with my surround processor with a built-in advanced room correction and my crossover added. I had 2 occasions of calibrating for the speaker itself and the room 5 difference spaces for myself. In these cases, the speakers were always my current one. They just got tuned greatly, and once and only once, my Grammy-nominated mastering engineer friend heard it and said it's good enough. Obviously not as good as one in The Mastering Lab in Ojai, CA, but acceptable to his high standard. Everyone who listened to it didn't have any major complaint and some of them are good at acoustics professionally. This is why I am not too worried about fine tuning for the speakers and the room.
Further strengthening it, I brought my new crossover system to the DIY friend's system, and it took only a few minutes, after connecting so many channels of amplifiers to the drivers which takes a while, to get the system up and running to at least an acceptable(actually 'pretty good') level to those 2 experienced audiophiles. I'd call them more of 'audiophile with objective taste', meaning they happen to like they 'good' speakers sound(good from the viewpoint of people with good engineering experience). I think it's because they have good amount of concert experience and know what the real performances sounds like. Obviously some mechanical tunings must have been done by the owner, but passive crossovers weren't there, so no electrical tuning other than the room correction.
Unlike last time when Wilmslow did such things on my behalf, I think I will do something I can possibly do this time, but I trust in what good room correction can do, and will use it extensively. I strongly recommend folks here to audition some good system using Dirac Live, Audyssey or Lyngdorf. BTW, Stenway has a Lyngdorf-based super-highend boxless speaker systems using Lyngdorf surround processor with its own room correction S/W and their class-D(must be the descendent of TacT class-D) with built-in DSP crossovers to drive the speakers tri-amped.
Looking through specs of 8" woofers, I seem to find that seemingly suboptimal FR curves with rapid rolloff in the low side are due to the open baffle measurement. I was wondering about Silver Flute wool woofers' crazy flat curve, and now am suspecting it was measured in a tuned box. Is this a correct understanding?
Why don't you download a box simulator like WinISD and see for yourself what kind of low end the drivers are capable of in your desired volume?
https://midwestaudio.club/?page_id=14662
Can you provide a link to the drivers in question.
https://www.madisoundspeakerstore.com/approx-8-woofers/silver-flute-w20rc38-08-8-wool-cone/
If it’s the above they are Madisound own Brand of cheap and cheerful drivers. Those are magazine curves. 10 db division and smoothed. The curve is in the the tuned response. I would personally pass on them.
My apologies for taking the thread down a controversial rabbit hole.
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These are some real tests SB acoustics 2 inch dome. It’s the real deal. The dipoles be easily EQ out with dsp.
Frankly if it were me l would stick with SB for the purposes of selecting drivers in this situation. They are not in the Volt league but they are not $$$ prices either. SB are a major OEM driver manufacturer.
Frankly if it were me l would stick with SB for the purposes of selecting drivers in this situation. They are not in the Volt league but they are not $$$ prices either. SB are a major OEM driver manufacturer.
Attachments
Yes, that is the link I looked at, and thank you very much for your clarification. I will keep looking in the 8" options.
Those, especially 3rd one looks great. Happy to save some $$$. Hopefully it will get along well with Scanspeak Illuminator 7" paper cone. If that doesn't work out, I can opt for VM527 later. Xmax was the main concern for the Satori dome, but covering (700~850) to 4000, hopefully it won't be overloaded at my highest listening level, lol.
Below is a link to a smart phone App with a data base of 5000 drivers to do hand held enclosure simulations.
This will help you sort through the functional performance aspects of different woofers. Performance limitations are easily verified.
It’s portable and includes a variety of curves to inform you about what a woofer will do in an enclosure. This includes various bass reflex and sealed alignments. Electrical EQ and other custom options are included in the free version. It’s better than Bassbox imo.
Joseph Crowe is becoming mature at testing drivers and has a true low distortion mic.
This link provides an understanding of objective measurement and subjective comments from someone who has tested a number of drivers.
I think the point of researching and taking on some of the subjective comments is that its common sense unless you are prepared to buy 1/2 dozen drivers to personally evaluate.
This is a premium aluminium woofer.
Not cheap either.
https://josephcrowe.com/blogs/news/purifi-ptt8-0x04-nab-02-8-aluminum-cone-woofer
Here the same driver profiled on the Voice Coil Test bench by Vance Dickason who has worked in the industry for 40 years.
https://audioxpress.com/article/test-bench-the-purifi-audio-ptt8-0x04-nab-02-8-aluminum-cone-woofer
Quote Vance Dickason:
“As with all the Test Bench reports I publish in Voice Coil magazine, I regret not being able to design these drivers into a system and do a proper subjective evaluation.”
Obviously a subjective evaluation matters
This will help you sort through the functional performance aspects of different woofers. Performance limitations are easily verified.
It’s portable and includes a variety of curves to inform you about what a woofer will do in an enclosure. This includes various bass reflex and sealed alignments. Electrical EQ and other custom options are included in the free version. It’s better than Bassbox imo.
Joseph Crowe is becoming mature at testing drivers and has a true low distortion mic.
This link provides an understanding of objective measurement and subjective comments from someone who has tested a number of drivers.
I think the point of researching and taking on some of the subjective comments is that its common sense unless you are prepared to buy 1/2 dozen drivers to personally evaluate.
This is a premium aluminium woofer.
Not cheap either.
https://josephcrowe.com/blogs/news/purifi-ptt8-0x04-nab-02-8-aluminum-cone-woofer
Here the same driver profiled on the Voice Coil Test bench by Vance Dickason who has worked in the industry for 40 years.
https://audioxpress.com/article/test-bench-the-purifi-audio-ptt8-0x04-nab-02-8-aluminum-cone-woofer
Quote Vance Dickason:
“As with all the Test Bench reports I publish in Voice Coil magazine, I regret not being able to design these drivers into a system and do a proper subjective evaluation.”
Obviously a subjective evaluation matters
Cool. Your getting it
#In my previous thread it’s for illustrative purposes. I doubt anyone would lay out $700 on each driver without personally having tied a number of lower cost drivers previously.
#If your confident that your not going anywhere the limits of a competitively priced driver then it will most likely be okay.
# Higher priced drivers used for monitoring such as Volt offer higher output with low distortion and reliability. Their woofers have dual spiders which makes them more robust.