hi gentlemen. i am looking for a new design to build with the budget limit of $1000. little over that would be acceptable as long as its desirable enough. my current consideration is RC3R from selah audio. however from reading on this forum the open baffle design choice becomes much more intriguing. is there any such design incorporating a ribbon tweeter? because that is the only requirement of my project. im a ribbons guy 
thank you for all the early replies. i'm dying to make some saw dust again
thank you for all the early replies. i'm dying to make some saw dust again 
That is a healthy budget. Dream budget for me actually
First of all, invest $60 for measurement tools.
Then $200 for 8-channel gainclone. Now you're left with $700+
First option, I'd buy Orion plan and substitute the drivers, e.g. W22=> L22 and TCF => 27TDFC, or perhaps Neo BG3. Find any 12" or 10" woofers which fits the budget with good xmax and cost.
Alternatively:
- DCX2496 xo: $250
- Zaph ZA14 + DQ tweeters (or Neo PDR) : $160. Mount them on narrow baffle 20cm x 110cm and eq with the dcx. Use the measurement tool outside to get notch q, depth, and f.
- H-frame woofer with 10" or 12" woofers.
First of all, invest $60 for measurement tools.
Then $200 for 8-channel gainclone. Now you're left with $700+
First option, I'd buy Orion plan and substitute the drivers, e.g. W22=> L22 and TCF => 27TDFC, or perhaps Neo BG3. Find any 12" or 10" woofers which fits the budget with good xmax and cost.
Alternatively:
- DCX2496 xo: $250
- Zaph ZA14 + DQ tweeters (or Neo PDR) : $160. Mount them on narrow baffle 20cm x 110cm and eq with the dcx. Use the measurement tool outside to get notch q, depth, and f.
- H-frame woofer with 10" or 12" woofers.
ugh. computer xo and active ones are a turnoff for me. with this budget im hoping to get to finally try out some mundorf supreme or jantzen at least. and hanging the drivers doesn't seem like the best solution. i would think that there'd be micro shaking of the axis from being hung and not secured entirely. yes this is also to become my dream speaker since i only have room and time for one pair. what is the need for an 8 channel amp, may i ask? i already have a rather formidable goldmund clone that i sadly wasn't the one to diy... xP. once again thank you for your inputs, gents.
Acoustic output of a dynamic driver on open baffle is not flat, hence require shaping either with digital or active xo .. alas, multi-amps.
The challenges are:
- dipole peak
- -6db/oct at lower frequency.
- baffle size: smooth polar response vs. low freq. output
Good luck doing this with passive components.
The challenges are:
- dipole peak
- -6db/oct at lower frequency.
- baffle size: smooth polar response vs. low freq. output
Good luck doing this with passive components.
Try it, and you'll know
And for those 8 channels of amps, maybe 3-way fully active + stereo subs?
I'd like to suggest 4 channels for active 2-way (total 3-way) in the first place. You'll need at least active xover at the bass which will need some EQ.
I agree with the other replies here: just forget passive XO with OB speakers, it will never work well. I suggest you start out with a DCX2496 XO and a stack of inexpensive amps, like the gainclones.
I just fell in love with the sound of baffle-less dipoles. They are easy to make, and sound fantastic! You will need something more than a 10" woofer, but a decent 15" will work unless you want to play very loud. Add a nice 8" or 10" paper mid/woofer and a dipole ribbon tweeter like the Neo3 you should be there.
I just fell in love with the sound of baffle-less dipoles. They are easy to make, and sound fantastic! You will need something more than a 10" woofer, but a decent 15" will work unless you want to play very loud. Add a nice 8" or 10" paper mid/woofer and a dipole ribbon tweeter like the Neo3 you should be there.
i'd like to mention that i'm a complete noob at designing speakers as if my questions didn't make it obvious enough.. xD. i'd rather stick with a published and proven design so that i don't end up shooting myself in the foot at some point. sunflower would be appealing enough if it had ribbons.
Certainly a wise decision, but I don't know of any completely passive and completely OB system with a ribbon on top. There must be reasons for people to avoid that challenge.
hi gentlemen. i am looking for a new design to build with the budget limit of $1000. little over that would be acceptable as long as its desirable enough. my current consideration is RC3R from selah audio. however from reading on this forum the open baffle design choice becomes much more intriguing. is there any such design incorporating a ribbon tweeter? because that is the only requirement of my project. im a ribbons guy
You could consider my NaO Mini design. Substitute an Aurum Cantus G2Si for the tweeter and appropriate mods to the tweeter x-o and you on.
An externally hosted image should be here but it was not working when we last tested it.
I avoid ribbon tweeter because of the bad vertical dispersion. I made a complete passive open baffle and it works very well, nothing more or less than an active one, just need a very strong amplifier.
Yes it exists a passive OB with a ribbon. Looks like a lot my project, we use the same woofer. Notice, my project was in its half life of design
.We should avoid Ribbon tweeter in an active system, they are very fragile and don't resist to the "plop" of the electronic.
I think "PreSapian", you have a large choice of DIY projects, passive, semi passive and full active ... I can say full active is easier to make. If you absolutely want a ribbon tweeter, the project must be passive or semi-passive, you must have a passive crossover on the ribbon tweeter.
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how much of an influence does vertical dispersion have when you only ever plan on listening to the tweeter at the ear level? yes, i think selah audio monitors are fantastic deal and i'll probably end up going with rc3r unless something here really catches my attention. and looking through all 28 pages of OB pictures thread... nothing did
It will affect the frequency response of the floor and ceiling reflections, and also the later arriving "ambience" in your room.
I recommend damping the floor and ceciling reflection anyhow, so it might not be a big problem after all.
I disagree. MJK has shown the way:
http://www.diyaudio.com/forums/full-range/108751-new-mjk-baffle-article.html
You should also check out Martin's other OB projects and articles.
I even built one of the little passive OB's, though with some mods. Look down to page 48 of the thread (about post #479 IIRC.)
And if you want to design your own OB, MJK's MathCAD worksheets are a real bargain!
Cheers. Jim
I agree with Jim, and disagree with this statement. A passive three way OB system should be possible and sound great.
If the ribbon tweeter is the requirement for this design, then you need a midrange driver that has a similar efficiency. Start by designing the passive crossover between the midrange and tweeter in a similar manner as a closed box, if you find a closed box crossover already done for the ribbon tweeter and midrange driver start with that scheme.
For the bass driver you will need an efficient woofer, probably a 15" pro woofer that is 6 to 10 dB more efficient then the midrange/ribbon, that has a Qts > 0.7 with 1.0 probably the best. Size the baffle width to give the hump between 200 and 400 Hz and then design the crossover to the midrange taking advantage of the OB hump. Maybe low pass the woofer at 200 Hz and high pass the midrange at 400 Hz.
The key is that the OB needs to be fairly wide (> 18" for example) so that both the midrange driver and the ribbon tweeter operate above the OB hump. The width in combination with the woofer Qts will determine your low frequency response. All simple passive crossovers with a single amp should be adequate.
I believe this design path is possible, the details need to be carefully worked out.
I didnt say it wouldnt work - I said it would not work *well*. You will need to compromize a few things. Wide baffle will give smooth freq. response, but worse off-axis behaviour. Also - where can you find a really good pro 15" with very high Q and good efficiency? High Q means low magnet strength and low efficiency. To EQ the woofer with a passive filter also means using a very large series coil for the woofer. I dont think thats a brilliant idea. Just my 0.02$
Well I have to sort of agree and disagree. I'm not a fan of wide baffles because they can create problems above the "hump" MJK speaker of. This depends a lot of the directionality of the drivers used and listening distance. Also, if you look at the passive design MJK discusses in his pdf the last figure shows that the woofer response only extends to about 47 Hz and then rolls off 3rd order below. So you have to decide if that is sufficient bass. Bass won't be boosted by room pressurization but it is possible that, depending on the room size and shape, an excited mode may provide the sense of deeper bass at the listening position. If you make the baffle such that the "hump" is around 200-400 Hz then my experience with 6" to 8" midrange drivers is that there may be problems in the response above that point. Adding damping to the back of the midrange can help that but then it's not really open baffle.
Not to take away from Mark's excellent as always efforts, but in the final analysis it is necessary to verify these designs, particularly through the midrange, with good measurement.
My first OBs were passive and wide. With this I had achieved nirvana no box speakers whatever price could match (except in quantity and slam). I have a clip in youtube (search "diapole speakers" - yes wrong spelling), and try to hear clips from YG Anat, or expensive B&W nautilus etc. Even in youtube you can notice the difference.
But yeah, active and smooth polar response (up to tweeter xo) due to narrow baffle is a different ball game. Such accuracy only could be obtained by line-level shaping. I'd call it Nirvana level II. The illusion is believable.
A nirvana level-III would be something around tweeter dispersion "discovery" like the work of mige01 in "beyond ariel" thread. Such speaker would have geddes-quality polar response, only front-and-back.
The smooth polar response is why, I think, SL's Pluto gives a very scary holographic image. Better than my narrow baffles. When I listen to the plutos for let's say 20 minutes, suddenly my brain thinks... hold on, what are these pipes doing here ! Such is the illusion. Unfortunately they lack the "colourless" sound of OBs. The box/pipe makes it like photograph having a colour shift.
Hence a Nirvana level-III would be listening to a pair of dipoles and the mind would be confused what are these panels standing there for. Not achieved yet, but close, very close, with narrow baffles and impossible to do with large panels.
But yeah, active and smooth polar response (up to tweeter xo) due to narrow baffle is a different ball game. Such accuracy only could be obtained by line-level shaping. I'd call it Nirvana level II. The illusion is believable.
A nirvana level-III would be something around tweeter dispersion "discovery" like the work of mige01 in "beyond ariel" thread. Such speaker would have geddes-quality polar response, only front-and-back.
The smooth polar response is why, I think, SL's Pluto gives a very scary holographic image. Better than my narrow baffles. When I listen to the plutos for let's say 20 minutes, suddenly my brain thinks... hold on, what are these pipes doing here ! Such is the illusion. Unfortunately they lack the "colourless" sound of OBs. The box/pipe makes it like photograph having a colour shift.
Hence a Nirvana level-III would be listening to a pair of dipoles and the mind would be confused what are these panels standing there for. Not achieved yet, but close, very close, with narrow baffles and impossible to do with large panels.
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Interesting, I don't have same listening impressions with dipoles, as others. only reason I use them is space saving and ability to use huge woofers. otherwise sound is almost identical to boxed speakers. even Linkwitz mentioned how similar his Plutos sound to Orions. yes, dipole bass is different, but before using two 15" U-frame subs I used 8in ported sub 
, not a fair comparison.
, not a fair comparison.
I understand what you write. You say a lot of things but I give you my point of view, a little slight different. I talk about things I experiment. I made active and passive OB. I began by a passive one, I had a lot of difficulties, at the end I made an active one and its works. I read all publications (thanks for their great website
) from SL, MJK, and JK. I understand what happened and I managed to make a decent passive OB.All designs in HiFi need compromise ? Isn't it ? You cannot have good bass extension and narrow OB baffle ?
Large ? what is a large baffle ? My open baffle width is 40cm ? it is large ? and the last OB full-range I made is 30cm width. Just as large as the driver.
The sensitivity of the passive OB speaker is low 83dB/2.83V.
If the debate is about passive versus active. During a long time I thought active is better than passive till I have had a good amplifier. But if you never experiment this, you cannot believe this. I think it's easier to make a better active design for practical reasons (e.g. better amplifier inter-modulation).
Large inductor is to equalize in the bass and lower midrange, why is so problematic ? Passive box subwoofer, 3 ways box, use large inductor.
For the driver, it is problematic to find high end drivers design for close box and open baffle. A majority of drivers are design for bass reflex. You have to equalize a lot and only with active filter.
Things are not simple or black or white. You often have exceptions
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