What is your implementation with the miniDSP? One would imagine that taking a stream of music through an ADC, plying with it mathematically, and then a DAC has to do something to it. Although, I can't hear a difference when I run it through the miniDSP and select bypass on the EQ's.
Have a listen with a good pair of headphones at the mono sound clips I have and tell me if you think they sound bad? This is a slot OB woofer with a full range top - all budget priced drivers ($40 for all seven used) - probably less than the cost of a single super cap in XO of the OB11. http://www.diyaudio.com/forums/full-range/249984-cheap-fast-ob-literally-8.html#post3807593
My point is though that single full range can be very good for a monitor as it can be flat and neutral. Higher SPL's may be a problem but if 105 to 107dB dB is enough, then it can work - even with the evil DSP in between.
I'm thinkin' bass extension might have been quite good.
Maybe Scott will post a sim of the DBR.
jeff
I built a pair - the bass extension was good.
There's a sim on page 2 of the plans:
http://www.frugal-phile.com/boxlib/woden/MarkAudio-A12-DBR-290610.pdf
What is your implementation with the miniDSP? One would imagine that taking a stream of music through an ADC, plying with it mathematically, and then a DAC has to do something to it. Although, I can't hear a difference when I run it through the miniDSP and select bypass on the EQ's.
Have a listen with a good pair of headphones at the mono sound clips I have and tell me if you think they sound bad? This is a slot OB woofer with a full range top - all budget priced drivers ($40 for all seven used) - probably less than the cost of a single super cap in XO of the OB11. http://www.diyaudio.com/forums/full-range/249984-cheap-fast-ob-literally-8.html#post3807593
My point is though that single full range can be very good for a monitor as it can be flat and neutral. Higher SPL's may be a problem but if 105 to 107dB dB is enough, then it can work - even with the evil DSP in between.
Just a suggestion. Run your FR driver with a highpass that is set low enough not to effect the response. You will be using the internal processing of the dsp, but can then do a true with and without comparison. For me, plugged in after an oppo, using same scenario, th dsl added a veil. Then again, I was using usb power and not independent supply for the dsp. There is no pre-existing prejudice in my experiment as I love the concept of the dsp. Ill have to try it with dedicated psu. Driver that showed the issue was eNabled Alpair 10.2.
A few general thoughts:
-The DBR was as noted designed for the original Alpair 12, not the current A12P which will not work properly in it. Nor was it named by me. Although while on the subject, for those stating that response 'must' fall within xyz criteria of their particular definition, I should point out that the vast majority of studio monitors do not actually adhere to these criteria. A single driver monitor is not 'by far the worst performer' -that is just one take, to a set of criteria that are not necessarily universal.
-THD is of little value to my way of thinking. Distortion measures that actually show 2nd, 3rd, 4th, 5th harmonics individually on the other hand can be extremely valuable.
-Flat response can be an ideal to shoot for, although the BBC amongst many others (e.g. Yamaha) would take issue with a blanket assertion of this type, as would many studio / mastering engineers. However, as Jeff notes you can have a large number of different speakers, all of nominally the same type & notionally designed for flat anechoic response, that sound very different due to different crossover frequencies, slopes etc. along with distortion numbers &c. The data when available is certainly valuable -more knowledge = hopefully better informed choice providing you know what you're about. However, the optimal set of compromises varies with requirements / circumstance, &, with the dark inevitability of Greek Tragedy, what meets one set of criteria / requirements will not necessarily meet others; it's not a fixed point.
-The Hartmann cabinets were not designed for the current generation of Alpair 10 drive units; they were designed for the old 10.2 which had rather different parameters. As it happens, in basic alignment terms I thought it was mediocre for the design driver, since it was bordering on QB3, which is rarely practical, though the high aspect ratio of the vent (intentionally or otherwise) may have damped things a little. Slightly ironically, IMO, the alignment should prove a somewhat better compromise with the current drivers.
-The DBR was as noted designed for the original Alpair 12, not the current A12P which will not work properly in it. Nor was it named by me. Although while on the subject, for those stating that response 'must' fall within xyz criteria of their particular definition, I should point out that the vast majority of studio monitors do not actually adhere to these criteria. A single driver monitor is not 'by far the worst performer' -that is just one take, to a set of criteria that are not necessarily universal.
-THD is of little value to my way of thinking. Distortion measures that actually show 2nd, 3rd, 4th, 5th harmonics individually on the other hand can be extremely valuable.
-Flat response can be an ideal to shoot for, although the BBC amongst many others (e.g. Yamaha) would take issue with a blanket assertion of this type, as would many studio / mastering engineers. However, as Jeff notes you can have a large number of different speakers, all of nominally the same type & notionally designed for flat anechoic response, that sound very different due to different crossover frequencies, slopes etc. along with distortion numbers &c. The data when available is certainly valuable -more knowledge = hopefully better informed choice providing you know what you're about. However, the optimal set of compromises varies with requirements / circumstance, &, with the dark inevitability of Greek Tragedy, what meets one set of criteria / requirements will not necessarily meet others; it's not a fixed point.
-The Hartmann cabinets were not designed for the current generation of Alpair 10 drive units; they were designed for the old 10.2 which had rather different parameters. As it happens, in basic alignment terms I thought it was mediocre for the design driver, since it was bordering on QB3, which is rarely practical, though the high aspect ratio of the vent (intentionally or otherwise) may have damped things a little. Slightly ironically, IMO, the alignment should prove a somewhat better compromise with the current drivers.
Last edited:
MLTL Alpair 10
View attachment Griffin-A10-MLTL-030611.pdf
I wonder if the result is the same folding chamber in two.
View attachment Griffin-A10-MLTL-030611.pdf
I wonder if the result is the same folding chamber in two.
I hadn't said anything yet, but I blasted a pair of those together last weekend (with some additional bracing) - and will probably populate with drivers tonight. If Jeff is interested I could drop them by for some listening
Also finished a pair of bespoke enclosures for Airborne FR179 - veneer wood cones with whizzer and phase plugs - actually quite a pretty driver.
nirvana - note that the Griffin enclosures cited were also for previous A10s - the new models, particularly the papers, are quite different, and while the 10P would "work" in the most fundamental sense, there's a good chance they'd be mis-tuned/aligned, and could be anywhere from slightly underwhelming to much worse
Last edited:
Sure, c'mon by.
Bring your fave demo CD's, as my wife has borrowed the batteries for my phono.
jeff
Last edited:
There is no "best" - as in "one ring for all" - least compromised for given situation, maybe
I've found that the simple MLTL format is a widely flexible topology, easily adjustable for T/S parameters of a wide range of drivers. Mind you, thorough computer modeling by experienced designers is only a wild-ast guess as to how a system will perform in your real world environment.
Then there's the aesthetic and WAF considerations - actually in many cases those come first. Since small enclosures often imply the use of stands, often a compact footprint floorstander is much more readily accepted, and can deliver better bass performance.
edit: pardon the "senior's moment", but have you yet determined what the constraints of enclosure dimensions might be for this particular application?
Last edited:
Mar-Ken10p ~26x38x26 cm (wxhxd)
Mar-Ken10pT ~25x47x26 cm (wxhxd)
Mar-Ken10pwT will be ~28x42x26 cm (wxhxd)
Classic Golden Ratio Mar-Ken10p will be ~28x45x19 cm (wxhxd)
They are the same volume inside.
dave
I do not really stress to the dimensions of the speakers. If pensil are the best, I will build the pensils. I want to discover the Mark Audio speakers in their best environments.
Yes. The Mar-Ken10.3T we built were medium wide, the fir Mar-Kels Bernie built were wTs of the same"size"
dave
I did a measurement and listening test to check this out here.
http://www.diyaudio.com/forums/full-range/247598-nautaloss-ref-monitor-26.html#post3808837
I could not hear difference. Measurements showed that miniDSP reproduced FR faithfully and imparted an overshoot in the impulse response, it actually smoothed and flattened the phase actually.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.