Dear Gurus! Suppose I should not spend on the MonAcoustic SuperMon Mini (because it's kinda expensive) and instead I want to build something in the same category/class myself: the ultimate passive desktop monitor for audiophile classical/instrumental/acoustics playing at low volume with high fidelity.
- No bass is necessary, 65 Hz - 20 kHz
- Insane details, soundstage
- Classical/acoustic/instrumental/indie rock. I don't care how heavy metal sounds. No pipe organs. No movies, no games, only music. I hope to crack those symphony orchestras, finally
- Low volume, firing directly at me at 2 ft distance. Practically headphones
- Not huge, should fit on the table around computer monitor, but can be deep. I can always pull the table away from the wall
- Perhaps sealed, because it should be easier to build
- Drivers about $200 each, could be a bit more if absolutely necessary
- Perhaps full range, because I guess it's much easier?
- I should not regret that I don't have Supermon Minis
Certainly nothing wrong with picking from the Mark Audio catalogue. I'm still enjoying my Planet_10 Mar-Ken7.3En speakers in Bamboo, but the Alpair A7.3 has been OOP for years, so the closest driver would probably be the Pluvia 7.2 HD. Or splurge for the fancy MAOP drivers: https://www.madisoundspeakerstore.c...agnetic-arc-oxidized-full-range-matched-pair/
Lot's of box options from the main Mark Audio website, or Dave @planet10.
jeff
Lot's of box options from the main Mark Audio website, or Dave @planet10.
jeff
For a nearfield desktop system, even the smaller MA 5 / 6 cm series could work quite nicely, and you won’t need 600hrs of Diane Bish to break them in.
(65*20000)^0.5 = ~ 1140.2 Hz mean
3440/pi/1140.18 = ~ 9.6 cm dia.
9.6^2*pi/4 = ~ 72.44 cm^2 Sd, so what's closest above/below?
3440/pi/1140.18 = ~ 9.6 cm dia.
9.6^2*pi/4 = ~ 72.44 cm^2 Sd, so what's closest above/below?
Nearfield listening would recommended rather beautiful detail with a AMT or Planar Tweeter.
Combined with either a 4" or 5" woofer to remain compact.
Many smaller drivers can do bass well these days. Little tradeoff is somewhat lower sensitivity to do this magic .
No concern with nearfield.
Nothing exotic or any nonsense enclosure things. Just a normal vented cab.
Forward facing port so if needed can be close to walls or actually work on a shelf if needed.
Been wanting to work out something similar for myself actually.
Somewhat a " mini" desk tower. Basically slightly taller form factor for the port to be easy.
And sitting at my desk would be ear level for the planar.
Otherwise with tall form and being deep. Can actually sneak in a side mounted 7" for bass
Which allows a smaller 3" mid so smaller planar can be crossed around 4 to 5K
rather than creeping down to around 3K for a 4" or 5"
Pushing towards 5" being the only feasible way to get low Fs for bass.
Which then pushes for a possible larger planar
Combined with either a 4" or 5" woofer to remain compact.
Many smaller drivers can do bass well these days. Little tradeoff is somewhat lower sensitivity to do this magic .
No concern with nearfield.
Nothing exotic or any nonsense enclosure things. Just a normal vented cab.
Forward facing port so if needed can be close to walls or actually work on a shelf if needed.
Been wanting to work out something similar for myself actually.
Somewhat a " mini" desk tower. Basically slightly taller form factor for the port to be easy.
And sitting at my desk would be ear level for the planar.
Otherwise with tall form and being deep. Can actually sneak in a side mounted 7" for bass
Which allows a smaller 3" mid so smaller planar can be crossed around 4 to 5K
rather than creeping down to around 3K for a 4" or 5"
Pushing towards 5" being the only feasible way to get low Fs for bass.
Which then pushes for a possible larger planar
I use Markaudio CHR-70's in sealed boxes. F3 is probaby about 80Hz but that still sounds very very good near field, They are really great littile desk speakers at a great price. Highly recommended ... but you could spend more on something else if you must.
I've come to think that adding a tweeter to help an already small main driver may be trying to shift the burden from an amplifier problem rather than the driver itself lacking ability.
The CHP-90 is about as big as I would comfortably go for paper FR in a desktop format, I think. It's a good size for adequate bass. I went with 14L sealed, making it soft but extended. Others may be able to advise on how to achieve more oomph with other box options. HFs blend very nicely, though occasionally give me the impression that different parts of the cone are doing different things (lending credence to "EnAble" cone mods). While the Alpair 5 is absolutely tight in that regard and would hold up against a ceramic Accuton C50 (while playing 3 octaves more bass!).
My palm-sized "100W" (laptop PSU powered) class-D does the job but it's an Achilles heel. What it really wants is a 5W class-A lead weight that's made for full range speakers. Maybe the Alpair 7MS could go one better, but see the impedance plots below:
Alpair 7, climbs past 20 ohm @ 15 kHz, so a normal class AB or D amplifier may make it sound quite harsh above 10kHz, unless something drastic is done like adding resistance in series, e.g. 10 ohm. A more advanced hack that won't affect the bass could be a 220u - 1000uH air cored inductor, which will demodulate and de-emphasise the treble, and then use EQ to adjust the tonal balance.
CHP-90: at high frequencies it actually climbs a lot less despite being a bigger speaker.
Meanwhile the Pluvia 7HD impedance looks incredible on paper, and probably sounds better than the Alpair on class-D without any mods, but the Alpair probably has the most potential because of the removed spider.
The CHP-90 is about as big as I would comfortably go for paper FR in a desktop format, I think. It's a good size for adequate bass. I went with 14L sealed, making it soft but extended. Others may be able to advise on how to achieve more oomph with other box options. HFs blend very nicely, though occasionally give me the impression that different parts of the cone are doing different things (lending credence to "EnAble" cone mods). While the Alpair 5 is absolutely tight in that regard and would hold up against a ceramic Accuton C50 (while playing 3 octaves more bass!).
My palm-sized "100W" (laptop PSU powered) class-D does the job but it's an Achilles heel. What it really wants is a 5W class-A lead weight that's made for full range speakers. Maybe the Alpair 7MS could go one better, but see the impedance plots below:
Alpair 7, climbs past 20 ohm @ 15 kHz, so a normal class AB or D amplifier may make it sound quite harsh above 10kHz, unless something drastic is done like adding resistance in series, e.g. 10 ohm. A more advanced hack that won't affect the bass could be a 220u - 1000uH air cored inductor, which will demodulate and de-emphasise the treble, and then use EQ to adjust the tonal balance.
CHP-90: at high frequencies it actually climbs a lot less despite being a bigger speaker.
Meanwhile the Pluvia 7HD impedance looks incredible on paper, and probably sounds better than the Alpair on class-D without any mods, but the Alpair probably has the most potential because of the removed spider.
Are MAOP 7 full range the best full range any money can buy? As I want to avoid messing with crossover full range saves so much that it's better to pick the best possible.
Also I wonder why Supermon Mini still has a ribbon tweeter with their MA full range driver, is it not covering the high frequencies already?
I plan to build a separate subwoofer anyway, so the low frequency cutoff doesn't matter. 65 or 75 Hz is enough. I'd rather have the ultimate mids and highs and worry about bass later.
Thanks for all the replies, very helpful!
Also I wonder why Supermon Mini still has a ribbon tweeter with their MA full range driver, is it not covering the high frequencies already?
I plan to build a separate subwoofer anyway, so the low frequency cutoff doesn't matter. 65 or 75 Hz is enough. I'd rather have the ultimate mids and highs and worry about bass later.
Thanks for all the replies, very helpful!
Why? Something wrong with the amplifiers? That's a pretty minimal rise by most standards (the motors aren't full symmetric drive but they're not far off) & the reduced current draw in the HF, where it's already fairly minimal, generally makes for a featherweight load. I can't say I've ever had any issues with solid state, either A, AB or D, and I'm still [over] sensitive to HF hash. I normally run class D monoblocks myself. Narry the slightest issue, certainly no change in FR etc. relative to anything until you start shifting to high output impedance amplifiers, which will tend to follow the impedance curve & put more emphasis on rises from a nominal.
That's very drastic (!) unless you've a lot of power to burn & you're wanting to shift quite close to current-source territory. If you started with, say, a Pluvia 7HD, the biggest audible effect would be to kick effective Qts up from around 0.58 to about 1.25 & drop voltage sensitivity to roughly 78dB 1m/2.83v. I can't honestly say I've heard of any requirement like that -granted, I haven't been looking though.
A 1mH inductor will not demodulate the treble, but it will certainly put a modest LP in place above about 500Hz which may level off a little in the 5KHz > region (would need to check properly & only on my laptop at the moment).
Will your head be in a virtual vise, neck in a brace, and spine always resting against the chair, whose legs are permanently fixed to the floor? Otherwise, what you hear will vary a great deal moment to moment especially near-field.
That said, I've done (not exhaustive) maybe a half-dozen diy experiments with the potential to be near-field ultra-fi at smaller-scale classical music, judged by ear against memory of >100 live concerts mainly front-row. They are among my posts to the Fullrange Photo Gallery (recent 10 pages) and elsewhere in the Forum. I'd single out just the first (as in my first diy) and last:
HeilEve AMT/honeycomb 7L TL after Eve Audio SC-205; one might buy the active monitors then replace the guts with passive series 1st-order XO and board-inserts forming a transmission line; speakers raised ear-high.
Axia wide-uniform-dispersion reflector-point-source; earlier desktop version Elfenu had the 15" drivers merely wrapped and/or rear-covered by nested washbasins.
I'll mention a third, not ultra-fi but really simple: Alpair 10.3 in rotatable stainless bowls, subs under desk.
Last edited:
At your pricepoint and yet still quenching the thirst for a DIY project?……I’m going to say a pair of KEF Q150 bookshelf speakers while they’re still available and on sale……they’ll likely hit the $299 price point for Black Friday as they are being replaced with the Meta version.
The only weak spot of the KEFs is the enclosure……and the enclosure doesn’t fit your use case anyway. I’d build a taller, shallow box that’s slightly wider with a forward facing slot port at the bottom. Line the rear of the interior of the box with rock wool to kill as much reflected energy as possible. Have the baffle of each speaker be in line with your monitor screen as an extended baffle. With a shallow enclosure, a trans Lam build would be very nice, stiff and not very difficult.
The only weak spot of the KEFs is the enclosure……and the enclosure doesn’t fit your use case anyway. I’d build a taller, shallow box that’s slightly wider with a forward facing slot port at the bottom. Line the rear of the interior of the box with rock wool to kill as much reflected energy as possible. Have the baffle of each speaker be in line with your monitor screen as an extended baffle. With a shallow enclosure, a trans Lam build would be very nice, stiff and not very difficult.
Don't overthink this for a near field desktop. The CHR-70 sounds fabulous and is also inexpensive. A sealed box with no filtering, is all that is needed. It sounds top shelf yet the price is bargain basement. If you want more bass just stuff a little sub unde the desk at your feet. This speaker with an ACA Mini pumping some Nelson Pass class A bliss into it is as good as you will ever need for this application.
Save yourself a lot of trouble and money. Just buy a pair of Edifier R1700BT and enjoy it. Loud enough, more deep solid bass, crisp clean treble lovely smooth mid-range. You can add a sub, it already has the facility, you can wire them or just use BT direct from PC. they are small have internal DAC, electronic cross-over and amp for each woofer and tweeter, what more do you need.