Hello all, been a lifer in the audio industry,fueled by my first love, music, and recently bitten by the DIY bug. I have googled ad nauseam trying to gain some insights, unfortunately when it comes to understanding the complex interactions of all the parts my head is about to 🤯 What I am looking for is a floorstanding, narrow, high efficiency and passive xover. Some that seemed appealing are the Decware ZOB and the GR X-Static, this 1 is particularly interesting as there is a flatpak cabinet available. If I had my wood working tools set up where I currently live I would be inclined to build the cabinet, that being said I could probably build a cabinet if it isn't too complex.
2 vendors that often get smacked about here.
Have you read Martin King’s papers? http://www.quarter-wave.com/OBs/OB_Theory.html
dave
Is what I am looking for too much of a compromise for OB speakers? The width of the speaker is a big concern, that's what attracted me to the Decware and GR designs, but from the little that I have been able to wrap my head around most are fairly large baffles to deal with bass cancellation?
As to baffle shape Linkwitz has signiifcant information.
The big problem with OBs is that shape of the baffle siginifacntly affects the response of the loudspeaker.
A narrower baffle means the bass starts canceling at higher frequencies so more EQ (and power & excursion capability) is needed and it also affects the response higher up. A narrow OB needs to have way more bass driver(s) than if they were not on an OB. Why you often see 1 or more 15” or even 18” bass drivers.
We built and heard many OBs. I am not a fan. If you want a tall narrow loudspeaker that does bass, and does not require EQ then look at ML-TLs.
dave
The big problem with OBs is that shape of the baffle siginifacntly affects the response of the loudspeaker.
A narrower baffle means the bass starts canceling at higher frequencies so more EQ (and power & excursion capability) is needed and it also affects the response higher up. A narrow OB needs to have way more bass driver(s) than if they were not on an OB. Why you often see 1 or more 15” or even 18” bass drivers.
We built and heard many OBs. I am not a fan. If you want a tall narrow loudspeaker that does bass, and does not require EQ then look at ML-TLs.
dave
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Ugg’s suggestion is the thidd site loaded with technical information.
You have some reading to do ;^)
dave
You have some reading to do ;^)
dave
Slowly working my way through Martin's paper, and it sounds like it might be what I am looking for, thanks again dave!
I had been wondering about some sort of hybrid design using a pair of woofers, front and back, in a transmission line with a full range driver in an OB.
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For good sounding midrange in open baffle, look for betsy. I use tweeter with betsy and sub below.
https://wildburroaudio.com/speakers/
Hi adason, that is starting to look like what I am envisioning. I have been assuming that wings could help when using a narrow baffle, ideally 12-15", but this will be in my Master Bedroom and having 2 folding doors in the middle of the room 😱
Then use a high enough Qt driver to achieve as low an upper mass corner (Fhm) as required since the 'box' only loads the driver up to it where its inductance controls its HF response:
Fhm = 2*Fs/Qts'
Qts': 2*Fs/Fhm
Fs: Fhm*Qts'/2
a narrow Open baffle (sort of)-
how about Adason's TC9FD18 MTM open back.
On top of a subwoofer enclosure.
Adason's MTM TC9FD
per Adason,"If you run it from 150Hz with sub, you will love it." post #1
post#12, #18, etc.
https://www.diyaudio.com/community/threads/mtm-with-tc9fd.308444/
Like this,
https://www.aussieaudiomart.com/det...s-studio-grand-reference-gold/images/2031438/
https://www.canuckaudiomart.com/details/649801804-nola-studio-grand-reference-gold-speakers/
Some subwoofer options (AmpsLab- Mike Chua)-
https://ampslab-spk.com/2018/05/17/crow/
https://ampslab-spk.com/2020/09/17/crow-ii/
https://ampslab-spk.com/2020/09/20/toucan-da/
etc
==========
Monacor Katana Open Baffle
dimensions metric 110 cm Hx 35 cm Wx 21 cm D or HWD 43.3"x13.8"x8.27"
https://www.monacor.com/products/components/speaker-technology/diy-/katana-m1/
https://www.manua.ls/monacor/katana-m1/manual?p=4
https://www.monacor.com/products/components/speaker-technology/hi-fi-speakers-/spm-205-8/
Comparable woofer? (foam surround- so what-it's cheap $7.50 cdn, $5.70 usd) see specs
https://qcomponents.ca/collections/...s/sammi-cwr200b20u-8-ohm-8-home-stereo-woofer
https://www.avforums.com/threads/open-baffle-kit-first-impressions.2443996/
https://foorumi.hifiharrastajat.org/index.php?threads/monacor-katana-m1.172110/
https://www.hifi-selbstbau.de/index...-monacor&catid=156&highlight=WyJrYXRhbmEiXQ==
how about Adason's TC9FD18 MTM open back.
On top of a subwoofer enclosure.
Adason's MTM TC9FD
per Adason,"If you run it from 150Hz with sub, you will love it." post #1
post#12, #18, etc.
https://www.diyaudio.com/community/threads/mtm-with-tc9fd.308444/
Like this,
https://www.aussieaudiomart.com/det...s-studio-grand-reference-gold/images/2031438/
https://www.canuckaudiomart.com/details/649801804-nola-studio-grand-reference-gold-speakers/
Some subwoofer options (AmpsLab- Mike Chua)-
https://ampslab-spk.com/2018/05/17/crow/
https://ampslab-spk.com/2020/09/17/crow-ii/
https://ampslab-spk.com/2020/09/20/toucan-da/
etc
==========
Monacor Katana Open Baffle
dimensions metric 110 cm Hx 35 cm Wx 21 cm D or HWD 43.3"x13.8"x8.27"
https://www.monacor.com/products/components/speaker-technology/diy-/katana-m1/
https://www.manua.ls/monacor/katana-m1/manual?p=4
https://www.monacor.com/products/components/speaker-technology/hi-fi-speakers-/spm-205-8/
Comparable woofer? (foam surround- so what-it's cheap $7.50 cdn, $5.70 usd) see specs
https://qcomponents.ca/collections/...s/sammi-cwr200b20u-8-ohm-8-home-stereo-woofer
https://www.avforums.com/threads/open-baffle-kit-first-impressions.2443996/
https://foorumi.hifiharrastajat.org/index.php?threads/monacor-katana-m1.172110/
https://www.hifi-selbstbau.de/index...-monacor&catid=156&highlight=WyJrYXRhbmEiXQ==
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For bass duties SB Audience do a 12” and a 15” designed specially for OB designs. They also have an OB design on their site.
http://www.sbaudience.com/index.php/application/
http://www.sbaudience.com/index.php/application/
Thanks all, a ton of interesting links! I will continue trying to educate myself, although I must say that a lot of the info is currently way over my head
Planet10 said that Decware and GR get smacked around, other than a couple of posts regarding Steve's questionable math allusions, illusions?, I haven't really seen negatives about the XStatics. I seem to be coming back to these as being possibly the right compromise for my present situation and knowledge. I am however concerned that the XStatics might not be a real improvement over my Revel F226Be.
I should probably add that what led me to OB speakers is that I am getting ready to order a TU-8900 and will likely need something more efficient than the Revels. Other options start to get expensive quickly. Also I love a 3D sound stage!
Planet10 said that Decware and GR get smacked around, other than a couple of posts regarding Steve's questionable math allusions, illusions?, I haven't really seen negatives about the XStatics. I seem to be coming back to these as being possibly the right compromise for my present situation and knowledge. I am however concerned that the XStatics might not be a real improvement over my Revel F226Be.
I should probably add that what led me to OB speakers is that I am getting ready to order a TU-8900 and will likely need something more efficient than the Revels. Other options start to get expensive quickly. Also I love a 3D sound stage!
Single ended tube amplifiers tend to have a highish output impedance. This means the loudspeakers response will be affected by the interaction of the high Rout with that impedance. It can be more important than the actual efficiency.
A real world example is that effiicent Klipschs (they tend to have optimistic specifications), bit quite ugly impedance so not really well suited to a SET.
BTW, being intersted in the TU-8900 myself, and it seems it sounds best with 2A3, so you have about 3.5w. I have had some very pleasant listening sessions with a 2A3 SET, even driving quite inefficient loudspeakers. Given that almost all amplifiers are run into clipping — most of the time we are listening at levels <<1w. Big rooms, and needing to play loud can eat up the power thou.
If i was looking to an OB with that amplifier i’d probably start thinking about biamping pretty quick. A nice SS Class AB/D driving 1 or 2 big drivers and the Elekit driving a nice FR as midTweeter (i’d likely chose MA MAOP 10.2 if the budget didn’t get in the way.
dave
Actually the 2A3 usage probably wouldn't be that demanding, least wise from what I have read, as this would be for more vocal and perhaps small ensembles. Of course what ya read and what ya hear, for all I know I will be seduced by the sound of 2A3 tubes and use them more than I anticipate.
I was surprised by the comment regarding Klipsch as I had always thought them to be a good match for SETs. I get that efficiency isn't everything but when you refer to ugly impedance a review on ASR, hardisj, Heresy, indicates minimum 3.6 ohms. It has become very apparent to me that my understanding is limited but if you can add to my knowledge base, that would be great.
I was surprised by the comment regarding Klipsch as I had always thought them to be a good match for SETs. I get that efficiency isn't everything but when you refer to ugly impedance a review on ASR, hardisj, Heresy, indicates minimum 3.6 ohms. It has become very apparent to me that my understanding is limited but if you can add to my knowledge base, that would be great.