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Open baffle loudspeaker

Brilliant! I might make something in the spring next year. It won't be a clone though. I've got some different bass drivers in mind to use with the Mark audio widebanders.
 
James said:
Can't comment about your specific design, but I recently built a pair of Troels Gravesen OBL-15 for a friend. They sounded effortless and remarkably lucid. If I didn't already have four pairs of loudspeakers at home, none of which I'm prepared to give up, I might be tempted to build myself a pair.
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James, Hi.

I did think about building a set of these myself some time back, did they boogie and how deep did they go, I'm guessing about 35-40 Hz or so.

Simon :)
 
darkmatter said:
I did think about building a set of these myself some time back, did they boogie and how deep did they go, I'm guessing about 35-40 Hz or so.
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Hi Simon

I heard them once only, when they were just running in. I thought they sounded rather articulate and surprisingly lucid in the midrange. They did not lack bass. If anything, I thought they might have a bit too much heft, but that's in the context of a room that I'm not familiar with and they had not been optimally positioned yet.

I hadn't measured their response, but they certainly sounded like they would reach 40Hz comfortably and cleanly.

James
 
Alan

They seem to model quite well from 30-35Hz up to about 500Hz They would go higher but you do tend to get a bit of distortion after the 500 (I think in most 15" drivers)

SPL 85db after the xover inserted and dependant on FR driver used.

A panel of 500x650mm ish. seems to work..




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Heres is something similar I built a while ago...just a bit of 18mm ply with a pair of Emenance 15" and Visation FR13 FR drivers, they measure real well and sounds superb...

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You need to add a divider between the two drivers or you'll get a suck out between 1-2k.

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With the divider its much better....:)

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337alant said:
Wow thanks Graham thats excellent :cool:
That Visitation driver looks very good
I also have a spare pair of Volt BM220.8 which are really flat in the mid do you think i could integrate them with the Celestions and add a tweeter ?
I see there is quite a different in the sensitivity.
https://voltloudspeakers.co.uk/wp-content/uploads/2014/12/BM220.8.pdf

Alan
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Alan

By using a mid / tweeter you are defeating the objective. FR drivers, if used/setup correctly do NOT have a xover point smack in the sweet spot and are a joy to listen too IMO. Open baffle speakers (again if built and setup correctly) have a speed and transparency which is beguiling and very unlike a restricted box speaker presentation.

As a starter for, the Visation FR13 is an amazing FR driver (I have a passive network for it) if you like. That fact that they cost about £10 each with a plank of ply and a few passive filter components your up and running with open baffles for well less than £!00. Those in the above post have deposed a friends pair of Srahanian Obelisks MKIIs. I know they look a pile of shite but he wont let me have e'm back to finish off....:) They need a better (thicker baffle board (25-35mm) laminated ply and MDF works well.
 
Auto-correct is having a field day with "Visaton".


I have a question - on these modular dipole systems, is there a technical reason for leaving a small gap between the panels? I see a lot of people do that, seems to me the OB would be more effective without the leaks?
 
[QUOTE="Yank, post: 3555868, member: 121120]

I have a question - on these modular dipole systems, is there a technical reason for leaving a small gap between the panels? I see a lot of people do that, seems to me the OB would be more effective without the leaks?[/QUOTE]

Its having the ability to 'change the drivers' and or their orientation within the chassis without having to cut 'another' sheet of mdf or ply.

I also believe (but not sure) that the small gap elevates/helps the 'suck out' (vacuum/pressure waves) the 15" drivers create which can effect the smaller FR driver in the OB setup. Im no expert but have built quite a few OBs over the past year or so..learnt by trial and error...There is quite an OB following now with lots of info on the interweb.
 
laverda said:
Alan

By using a mid / tweeter you are defeating the objective. FR drivers, if used/setup correctly do NOT have a xover point smack in the sweet spot and are a joy to listen too IMO. Open baffle speakers (again if built and setup correctly) have a speed and transparency which is beguiling and very unlike a restricted box speaker presentation.

As a starter for, the Visation FR13 is an amazing FR driver (I have a passive network for it) if you like. That fact that they cost about £10 each with a plank of ply and a few passive filter components your up and running with open baffles for well less than £!00. Those in the above post have deposed a friends pair of Srahanian Obelisks MKIIs. I know they look a pile of shite but he wont let me have e'm back to finish off....:) They need a better (thicker baffle board (25-35mm) laminated ply and MDF works well.
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Graham
Ah I see FR, the penny has dropped :rolleyes::D

Think I will have a go at this when I get some free time thanks for the info on the visitation, are they really only £15 ?
Like you I would probably do some thing simple at first to see if I like them, then something better if I do
What do you consider a very good upgrade from the visitation ?
Alan
 
If I get a round tuit at some point I may well have a go at an open baffle myself... not FR though! Probably 3 or 4 way, definitely active.
 
337alant said:
Graham
Ah I see FR, the penny has dropped :rolleyes::D

Think I will have a go at this when I get some free time thanks for the info on the visitation, are they really only £15 ?
Like you I would probably do some thing simple at first to see if I like them, then something better if I do
What do you consider a very good upgrade from the visitation ?
Alan
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https://www.reichelt.com/gb/en/visa...2uePF3wIVDPlRCh3D7ANfEAYYASABEgLJ5vD_BwE&&r=1

A better FR driver, Tang Band. ?? but there are lots available now.
 
Apologies compared to many on here I am sadly lacking in the knowledge and skills for making an open baffle speaker . This thread has though got me thinking . I have completed two speaker projects which were turning two ready built speaker models (Monitor Audio M11 , KEF 103) in to active units using DSP via the Minidsp unit plus the addition of Dirac Live software. These have both ended up producing much better sound than the passive versions and in the case of the Kef's they sound (well to me at least) superb much better than I ever thought .

Practical work on both these speakers was very limited which given my lack of skill (and very large clumsy hands) was essential . So having read the above I would like to consider making an open Baffle Two way unit . I do not have the knowledge and skills to combine the best two units to work together . I know full well that the DSP can correct many of the issues that can occur but I instinctively feel it is better to get the best match up you can first and do minor corrections to finesse the speaker rather than major work to correct basic imperfections (I hope this makes sense).

So can you advise either a Driver pairing that you are sure works (I would like to use either a 12" or 15" bass unit with a Tweeter) or perhaps a kit design that would be a good starting points. I would love to go full out and design and build my own with advice but this would be a little too out of my ability zone.

Any advice you can give would be appreciated .
 
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