This is why I prefer to listen to what a speaker can offer first because it can really throw out your crossover assumptions.
Old example: I had a 10" subwoofer and 3.5" FR, fully expecting a crossover point around 200 Hz "give or take", but NO. Although the Dayton PS95 was good down to 200, and the STX w27.400 was a bass monster, the sweet spot was still over an octave higher @ around 500Hz.
500Hz was based on an all-inclusive, in-room impression of the sound, when fiddling with software based active filters. I could have forced the matter, and rebuilt the FR enclosure for better mid-bass, but chose not to.
You know, that's sort of like saying you like a certain skin or hair color over another color in a (now suddenly) introduced beauty contest of arbitrary rules.
I'm an engineer, not a fashion maven. I let my hearing system tell me which one sounds better. If you want to change the way they appear, that's certainly up to the user and is comparatively easy. I'm okay with them as-is.
Chris
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In the 70s my father was in charge of forward planning for an engineering company and as part of that he assigned value to patents. This was before the patent system largely broke down though it was starting, the US system wasn't as absurd as it is today (and not followed by the rest of the world) and companies didn't have to collect vast numbers of nonsense patents in order to defend themselves against breaking the large numbers of nonsense patents held by their competitors. Anyway, he judged the cost of getting, maintaining and defending a patent worthwhile if the invention played a significant role in a turnover of around £1-2 million. Below this it wasn't worthwhile.
There is every chance that anyone designing and making anything is breaking umpteen nonsense patents held in the US. Most won't stand up in court in the US never mind in the rest of the world but, obviously, there are no guarantees when one goes to court. About the only invention one can't seem to patent in the US is a wheel which they do seem to check. Pretty much anything else is likely to get through and can be sorted out later in court. I seem to recall Microsoft or was it Apple managed to patent a vector?
As you say nobody is going to take a speaker DIYer to court in the US claiming they violated some nonsense patent that was granted for some "invention". That simply isn't what patents are used for today in the US. They are a (very expensive) deterrent.
If one looks at the challenge as how the costs can go below the given threshold of $1000, then here's my attempt (link): about $300 for the drivers and $90 for xo components (for pair).
Pretty equalized CTA-2034A graph though.
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Andy19191,
I basically agree (except the part where you try to rationalize infringing on a patent). In this particular case, you don't have to--only be aware that there is a patent still in force (US8284976) that attempts to patent the same thing as an earlier (now expired) patent US6411718. That's it. No reason to get too exercised by US patent law. See MEH Design with Coaxial Mid/Highs for further discussion on this particular subject.
When the day comes when I can do something about US patent law to change it to be more forgiving of furthering the state of the art for the benefit of all (as patent law says it is trying to do, while still giving inventors the chance to profit from their inventions without being usurped by others using their IP without paying royalties), I'll certainly weigh in with my opinions on that subject. As it stands currently, that's not necessary for the subject here that surfaced that issue.
Chris
I basically agree (except the part where you try to rationalize infringing on a patent). In this particular case, you don't have to--only be aware that there is a patent still in force (US8284976) that attempts to patent the same thing as an earlier (now expired) patent US6411718. That's it. No reason to get too exercised by US patent law. See MEH Design with Coaxial Mid/Highs for further discussion on this particular subject.
When the day comes when I can do something about US patent law to change it to be more forgiving of furthering the state of the art for the benefit of all (as patent law says it is trying to do, while still giving inventors the chance to profit from their inventions without being usurped by others using their IP without paying royalties), I'll certainly weigh in with my opinions on that subject. As it stands currently, that's not necessary for the subject here that surfaced that issue.
Chris
And that’s the beauty of old school voicing when building a speaker……measurements are great but to a flaw for the universal truth that everyone’s ear/brain mechanism is unique to them. Many of the great classic speakers we’ve all come to love at some point were created before advanced measuring techiques or Thiel/Small parameters were used.
Whenever I take on a design, i listen to each driver on a test baffle by itself with some basic hp/lp filters at volume to identify what it sounds like……it’s sonic signature or timbre so to speak.
One of the reasons why I didn't initially state the crossover schema used for the MEH is that, for a test, I ran my K-402-MEH without any crossover filters at all, just EQ. It actually works, i.e., the lower frequency drivers lead the upper frequency diaphragms by 90 degrees at the crossover bands. It works better with either first order crossover filters or DSP delays (with attenuating PEQs on each driver's stop bands) equal to 90 degrees of phase at the center crossover frequency. Using the natural notch cutoff frequencies on the lower frequency drivers (i.e., woofers, midrange diaphragm) helps to attenuate the lower frequency drivers more rapidly than in a flat baffle direct radiating loudspeaker than just first order.
It seems that only the horn profile is the one thing that you would like to get right. Rectangular or square straight-sided horns with mouth flares seem to work well, while other "traditional" horns having curved throats near their throat entrance (or throat slots) don't seem to work nearly as well. Attenuating the higher frequency drivers on their low frequency cutoff end using PEQs, etc. is an added safety measure for those drivers having more delicate diaphragms. For dual diaphragm ring radiator drivers, this seems to be a lower concern issue, since they are so so robustly designed.
Once of the reasons why I didn't state the exact drivers used is that it doesn't matter as much which woofer you use, as long as they have low Fs (below ~29-39 Hz free air) and medium/low Qts. This means a woofer having a somewhat larger motor than one typically used in bass reflex, and having a light cone than many bass reflex woofers. So a pair $120 12" woofers will work great. The only pricier option is a dual diaphragm compression driver. There are now multiple companies that produce these (BMS & B&C, perhaps others), and if you design your horn throat to be 1.4" instead of 2", you have even more choices, virtually any of which performs essentially flawlessly.
Not in the exact rules of the "challenge" per se, but perhaps by way of a mea culpa for not listing these first, to highlight the different approach (21st century, that is) to fulfilling the same need. Much more design freedom and typically noticeably lower driver costs to meet or exceed the same performance level as direct radiator setups.
Chris
It seems that only the horn profile is the one thing that you would like to get right. Rectangular or square straight-sided horns with mouth flares seem to work well, while other "traditional" horns having curved throats near their throat entrance (or throat slots) don't seem to work nearly as well. Attenuating the higher frequency drivers on their low frequency cutoff end using PEQs, etc. is an added safety measure for those drivers having more delicate diaphragms. For dual diaphragm ring radiator drivers, this seems to be a lower concern issue, since they are so so robustly designed.
Once of the reasons why I didn't state the exact drivers used is that it doesn't matter as much which woofer you use, as long as they have low Fs (below ~29-39 Hz free air) and medium/low Qts. This means a woofer having a somewhat larger motor than one typically used in bass reflex, and having a light cone than many bass reflex woofers. So a pair $120 12" woofers will work great. The only pricier option is a dual diaphragm compression driver. There are now multiple companies that produce these (BMS & B&C, perhaps others), and if you design your horn throat to be 1.4" instead of 2", you have even more choices, virtually any of which performs essentially flawlessly.
Not in the exact rules of the "challenge" per se, but perhaps by way of a mea culpa for not listing these first, to highlight the different approach (21st century, that is) to fulfilling the same need. Much more design freedom and typically noticeably lower driver costs to meet or exceed the same performance level as direct radiator setups.
Chris
A different approach running active (maybe not a real 3 way):
Upper part is open on sides (stuffing on back panel), lower part is closed.
Total cost 340€ for speakers (4 wire speakon connectors), 130€ for laser cut faceplate, 50$ for tolex => < 600€
Less than 200€ for Amp + noisy 1kW printer power supply (plenty on resale) modified with PC fans (150€) + 50€ custom alu faceplate
Total 850€, less than 1000€ with wood and glue
- Dayton DCS-205 (actively filtered and corrected)
- 4x VIFA TC-9 (8 Ohms, series parallel) (actively filtered and corrected, running full range)
- Dayton ND20-FB4 (first order filtering + passive attenuation > 4k)
- 2 x (Wondom "Gremlin" AA-AB32313 + Wondom 1701 DSP)
- SMPS (1kW for both)
Upper part is open on sides (stuffing on back panel), lower part is closed.
Total cost 340€ for speakers (4 wire speakon connectors), 130€ for laser cut faceplate, 50$ for tolex => < 600€
Less than 200€ for Amp + noisy 1kW printer power supply (plenty on resale) modified with PC fans (150€) + 50€ custom alu faceplate
Total 850€, less than 1000€ with wood and glue
Attachments
It is a 3". The 4 ohms is easier in the 1.2 k hz transition. Both are less flat after 3.2 k hz. Excelent choice, have the 8 ohms you listed. Very neutral and rewarding on instruments that are not always easy like brass. I would not use it with something bigger than a 8" and >500 hz, just because the size. I use it with the SB23NBAC and little 3/4 from Peereless around 3 k hz. But according the age and a little flipped towards the listener, the 10F almost can do the job alone. But some indeed cross it at 4 k hz as well.
Your exercice is not easy because if passive, coils are costing nowadays and if the filter is a little complex the bill can increase rapidly !
I do not list my 1 k bucks choice cause prices are different according the brand in EC.
If it’s a 3-way design (exclusively), then I’d do a B & O filler-driver design - this would greatly limit my driver choices in that the lower freq. driver would likely need to extend up to 1-2 kHz depending on the lower freq. limit for the tweeter relative to power-handling for the tweeter. Further the midrange would need to be broad & flat on the chosen baffle.
Duelund filter type ? Maybe a Kartesian or the Illuminator 4" is what one's needs. The dome from Dayton was not consistant enough in its fab. Maybe a big Bliesma or the "Ovulator" ScanSpeak line ? But any of them in the budget with the fligth.
I think a Bwalso's MEH design is less than 1 000 for the two channels and should be on the list.
I think a Bwalso's MEH design is less than 1 000 for the two channels and should be on the list.
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https://www.diyaudio.com/community/threads/filler-driver-ala-b-o.88135/page-2
Depending on the baffle, maybe a Mark Audio 10.3 for the filler. (..similar to the 10M.)
Depending on the baffle, maybe a Mark Audio 10.3 for the filler. (..similar to the 10M.)
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Sorry, maybe I was a bit rude. Saw your first post only and really didn't get it. Understand the simple fun now...
So, 1000.- € for the drivers / pair + crossover parts, enclosure comes on top?
Would plan for < 700 on drivers and > 300 for appropriate parts.
I propose classic 3-ways with simple concept, good HiFi drivers and cuboid encosures for easy build!
(Overall price for drivers only is stated, from the cheapest sources easily available to me in Germany that I could find, incl. all shipping costs)
1) CLEAR:
Scan Speak 26W/8534G00: https://www.scan-speak.dk/datasheet/pdf/26w-8534g00.pdf
SB Acoustics SB15NBAC-8 https://sbacoustics.com/wp-content/uploads/2020/02/5in-SB15NBAC30-8.pdf
Seas TAF/GB: https://www.seas.no/images/stories/prestige/pdfdatasheet/H1825-06_27TAC_GB_Datasheet.pdf
Diver procurement: 570.- €
Monkey coffin, CB 45~50L, Xover ~280Hz / 2,2kHz LR4
Bucking magnets for woofer + mid, serial notches for mid+tweeter breakup resonances in xover.
Similar to this, without the lower woofer, cut enclosure somewhat below the upper bass driver, make little wider:
2) DRY:
Scan Speak 22W/8534G00: https://www.scan-speak.dk/datasheet/pdf/22w-8534g00.pdf
Kartesian Wom120_vMS: https://www.kartesian-acoustic.com/copie-de-mid120-vhe
Bliesma T25A-6: http://www.bliesma.de/Datasheet-T25A-6.pdf
Driver procurement: 690.- €
Floorstander, vented 35-40l, Xover ~ 330Hz / 2,7kHz LR4
Bucking magnet for woofer, serial notch for tweeter breakup resonance.
Driver downsize and passive variation from this active speaker, prolong enclosure to get a floorstander, make little slimmer:
Enclosure similar this, with only the upper 22W woofer and without the Hypex Fusion, maybe then a bit lower and less depth:
(Obsolete CAD + Sim concept, the speaker in the pic above will stay in its current physical configuration)
3) SMOOTH:
SB Acoustics SB23NRXS45-8: https://sbacoustics.com/product/8in-sb23nrxs45-8-norex/
Scan Speak 15M/8631G00: https://www.scan-speak.dk/datasheet/pdf/15m-8631g00.pdf
Scan Speak D2604/833000: https://www.scan-speak.dk/datasheet/pdf/d2604-833000.pdf
Driver procurement: 690.- €
Floorstander, vented ~40l, Xover ~ 280Hz / 2,7kHz LR2
Bucking magnet for woofer, stepped baffle for tweeter better LR2 phase alignment.
Thinking about something comparable like this as my next project I aim for, still not decided for the woofer section as I don't have that strict budget restriction:
(With 2x SB17NRX2C35-4 in series per side)
As I own something like proposal 1) and 2) which is more or less finished now, it makes sense to me to build and have 3) for different, but good living room sound, and also the experience to develop a passive 3-way, it's my hobby and somewhat I have to build speakers, maybe you know that. I had a speaker as my very first build ~23 years ago with a Revelator 15W, a Vifa XT300, a coil, a cap and a resistor and I remember it to sound very sweet. Should work good with those drivers as LR2 with few xover components, when you optimize the baffle shape:
Topping PA5 II Amp and SMSL C100 DAC would be available for interface compability to both existing active chains, initially.
4) NOISEFREE:
I love the JBL LSR 6332 for its simple straight concept and linear output with power: https://jblpro.com/products/lsr6332
Aditionally
- distortion measurements of a very nice pro midrange driver published by @JFA in german diy-hifi-forum.eu (so that mid can get ******* loud),
- and a nice driver stock list from @Azrael for his next project he told me about, with a matching loud, high tesla airgap Sica tweeter
Faital 12RS430: https://faitalpro.com/en/products/LF_Loudspeakers/product_details/datasheet.php?id=151050115
Faital 5M8N-80 12 Ohm: https://faitalpro.com/en/products/LF_Loudspeakers/product_details/datasheet.php?id=101010101
Sica LP 90.28/N92TW: https://sica.it/prodotto/lp-90-28-n92-tw/
Driver Procurement: 650.- €
Monkey Coffin, vented ~50l, Xover ~ 380Hz / 2,5kHz LR4
Bring down the mid + tweeter high sensitivity with series resistors for local current feedback to match the woofer. Take resistors with low inductivity and high power capability (two in parallel for the mid) that they introduce no coloration or limitation. Gives 87-88 dB system sensitivity after BSC and a dB room gain, and you can drive them really hard.
@mayhem13 : Sorry again, but did I get the game?
Best regards,
Peter
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Very nice submissions Peter! Leaving an option for active or passive was part of the quest as these days with the availability of DSP and chip amp, it’s more viable than ever. Excellent driver choices as well.
As I’m getting older, managing and moving big speaker boxes is becoming a real P.I.T.A so hence the modular build.
It has also been my experience that when working with true ribbons, it is ESSENTIAL that the ribbon driver not be on the same baffle as dynamic drivers……dense baffles push their resonance right into the passband of the ribbon which does have an audible effect on the ribbon itself
As I’m getting older, managing and moving big speaker boxes is becoming a real P.I.T.A so hence the modular build.
It has also been my experience that when working with true ribbons, it is ESSENTIAL that the ribbon driver not be on the same baffle as dynamic drivers……dense baffles push their resonance right into the passband of the ribbon which does have an audible effect on the ribbon itself
I think 3-ways first and foremost need to solve a specific issue or fit a niche.
What I most need right now are floor-standing boxes for the piano keyboard to sit on, but consider the listening angle! So those are going to be 2-way at the most. Luckily I already have a superb old Eton 7" hexacone mid-woofer and old Accuton, probably crossed around 4kHz. I'm tempted to make it a TL instead of sealed, but I'm also thinking a vastly oversized sealed bass box will sound more natural. Thin-walled 10mm ply with just enough strengthening to prevent rattles.
Small FR bluetooth speakers always come in handy, but that's 1-way.
Pretty much the only place I could justify 3-way is for a big hi-fi, and for that I'd want the vertical projection to be a lot narrower than the horizontal. So: wave-guided ribbon tweeter (I don't know what model) in a D'Appolito arrangement. 12" woofers are great for WAW, but I think 8-10" would be a bit more civilised when there are 2 woofers per side.
Q: would the Visaton B200 fit in the budget??
What I most need right now are floor-standing boxes for the piano keyboard to sit on, but consider the listening angle! So those are going to be 2-way at the most. Luckily I already have a superb old Eton 7" hexacone mid-woofer and old Accuton, probably crossed around 4kHz. I'm tempted to make it a TL instead of sealed, but I'm also thinking a vastly oversized sealed bass box will sound more natural. Thin-walled 10mm ply with just enough strengthening to prevent rattles.
Small FR bluetooth speakers always come in handy, but that's 1-way.
Pretty much the only place I could justify 3-way is for a big hi-fi, and for that I'd want the vertical projection to be a lot narrower than the horizontal. So: wave-guided ribbon tweeter (I don't know what model) in a D'Appolito arrangement. 12" woofers are great for WAW, but I think 8-10" would be a bit more civilised when there are 2 woofers per side.
Q: would the Visaton B200 fit in the budget??
I don’t think it’s an issue with ’beauty’ per se…..but more the issue of form factor and what we’re accustomed to. Wide horn systems were never widely accepted only for a brief period at the pinnacle of home hifi. Now the AirPod and similar are the mavens of the public eye. I’d add for your benefit that there’s inherent beauty in engineering.
Wide horn systems have always dominated cinema halls, from Western Electric installations of the 1920's through to JBL installations today. Accuracy in sound reproduction sells cinema tickets. There are some auto sized Meyersounds at the local arts theater, big enough to be MEH but whonose?.
I was impressed by an Altec Lansing VOT installation in a cinema in 1966. It was recommended to us by our band director. I could never afford a VOT before the factory closed, neither did they have a dealer in my tiny city of Houston, TX. I have never been impressed by any 3 way, perhaps because I never heard any demonstrated on anything but acoustic guitar + tenors. AR3, KLH5. I heard a Klipschorn in 1978, demonstrating only trumpet/stringbass/brushcymbal jazz. Yawn! I now live in an even tinier city of only 2000000 now, where garbage 5 ways dominate the last sound marketers, rental furniture centers. Full range units (Polk) are for sale at a big box store, but they will not demonstrate.
When I saw a horn+15" from Peavey on craigslist that reminded me of VOT, I proceded to the local Peavey dealer. I got there a year or two before they went bankrupt. I took my own piano CD and they played it. I was impressed and bought some SP2-XT. They are huge but a pair are only 2/3 the size of the pianos & organs in the music room.
The only sound system dealers surviving in our city sell Bose & Yamaha. The Bose installations are small to vast arrays of 5" drivers. Ho-hum. The Yamaha installation I have heard leaves out all treble and bass, being apparently designed to amplify only speech. They miked the wood piano and ran it through that PA system anyway. Blah!
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