Open Baffle speaker

[wee tee cee]

Iam looking for a bit of advice.
I have read quite a few posts on open baffle speakers .I wondered how difficult they are to make,my wood working and soldering skills leave alot to be desired but im willing to learn.
Can anyone recommend a kit that would work well with a temple audio bantum or mono blocks as I can utilise either/Computer and DAC front end.
Music wise John Martyn is my datum point.I listen mostly to rock/blues /folk, very little classical or jazz.
I cant really place them any further that 50cm from a rear wall.Do I require a sub woofer to get the best out of them?
Any advice greatly received,
Regards Tony.

[John]

Hi Tony
Loads of options around the Open Baffle route
Here is a good place to start
http://theartofsound.net/forum/showthread.php?t=9466&highlight=open+baffle+diy
Your rear space might be a issue I have mine coming out quite a bit and for me this tends to get the best out of them, but will still work closer but you probarly not get the same scale.
DIY skills
If you go down the Bastanis or Hawthornes no need for soldering The Bastanis do not use Xover and the Hathornes come with the drivers
I see you based in Glasgow so Ali is up your way and has plenty of experience with with Open Baffles.
I intially built the first baffles myself using 3/4" ply it was not to hard with the Hawthorne approach and my woodworking skills are crap, but I would say for the drivers I use having 40mm mdf with extra isolation made a huge difference in the sound (not that they were bad before, but boy so much more) I got mine made up for me.
Bass: My drivers actually produce quite a bit of bass without the need to add anything its only if you want a lot more low down grunt.
They are severall ways you can do this I use a plate amp and the augee bass drivers which are pretty special in the bass. This allows me to use it in Dipole, so avoiding any box coloration. The amount of box colouration even in the Bastanis or the Linwitz approach ( http://www.linkwitzlab.com/woofer.htm ) to my mind add coloration and the only way to get round this is by using some kind or room correction approach; XTZ produce a sub plate that can do this but no need to do this with fully dipole approach.
Please feel free to ask more questions
i think Ali uses a Bantamn amp with his system I had the mini T on mine great in speed and detail but not enough clout with my speakers even with 95db A lot of people use lower power spud amps and this seems to be an approach that works well nut not tried this myself

[Ali Tait]

Tony, you're welcome to come over for a listen at the weekend if you like. I use a pair of Bantam Golds driving the OB's actively using a Behringer DCX2496-

http://img43.imageshack.us/img43/6818/imag0143q.jpg (http://imageshack.us/photo/my-images/43/imag0143q.jpg/)

[Spur07]

Hi Tony,

OB's are well worth the effort. My carpentry skills are very basic but I managed to cobble together a design based around the JE Labs OB. I used 3/4" ply. After a few tweaks it ended up as a mid size floor stander with an open back. The JE labs is good for bass but some people find it too large for small rooms.

If you buy 15" drivers like John you'll get excellent bass, but if you want to add extra I'd recommend following John's approach rather than buying a subwoofer or building a cabinet design. It really is a no brainer, easy to make and excellent VFM. I recently compared my drivers back to back - one in my OB and the other in a large cabinet design - it convinced me I'll never run these particular drivers in a box ever again!

[Ali Tait]

Yes agreed, this is the cheapest way to superb quality sound. My OB's have four Eminence Alphas at about 50 quid each, and a pair of Visaton B200's at about 200 quid. All you need then is a bit of wood for the baffle. The only downside is the limited WAF due to the size.

[John]

Yes its ridiculous how bloody cheap these can be and how good they can sound
Right now listening to some Dream Theater I am getting kick drums open soundstage and scale you not believe and just engrossed in the music I have no idea how much I have to spend to get anyway close but in the past I had a some WB Acts and the Wharfledale Opus 3 and not even in the same ball park

[aquapiranha]

Remember though it is not just a case of plonking some big drivers in a sheet of wood. There is some serious maths etc involved when considering the size and drivers. I had a little help on that from the man himself, Martin J King, the result being the OB's Ali is using now. FYI they are oak faced MDF with a sheet of 19MM BBply on the back - the idea here was to give enough strength and weight to the design, and at the same time use differing materials to help with damping. They are very simple to make though and if you can use a router you are halfway there. Have a look at the MJK site there are some great ideas and info there..

http://www.quarter-wave.com/OBs/OB_Theory.html

If, I said if I was going to make some more OB's I would be looking at a similar design, perhaps using a H frame for the bass drivers. Have a look here too..

http://www.wildburroaudio.com/projects.php

[John]

If you go down either the Hawthorne or Bastanis route they help you out with giving you baffle dimensions so you do not have to worry about the maths but a more bespoke method and then this will have to be taken into account
The hawthorne site is excellent and Darrel is a real gent who goes out of his way to help people
Ali has the baffle Steve made and everyone whos heard them really loves them so its a good place to start. Steve would of worked this all out so just be case of asking Steve if he is willing for you to copy

[Ali Tait]

You did a great job Steve. They sound superb.

[John]

Ps I been trying to champion OBs for awhile but as Richard speaker thread points out not many people are interested in speakers with big drivers

[wee tee cee]

Well,I ran it by my good lady regards the physical size of the OBs,she is OK.
My distance from the rear wall may be an issue but I dare say we can get round it.

[Spur07]

Remember though it is not just a case of plonking some big drivers in a sheet of wood. There is some serious maths etc involved when considering the size and drivers. I had a little help on that from the man himself, Martin J King, the result being the OB's Ali is using now. FYI they are oak faced MDF with a sheet of 19MM BBply on the back - the idea here was to give enough strength and weight to the design, and at the same time use differing materials to help with damping. They are very simple to make though and if you can use a router you are halfway there. Have a look at the MJK site there are some great ideas and info there..

http://www.quarter-wave.com/OBs/OB_Theory.html

If, I said if I was going to make some more OB's I would be looking at a similar design, perhaps using a H frame for the bass drivers. Have a look here too..

http://www.wildburroaudio.com/projects.php

making a design with folding panels (as above) is a good way of reducing the footprint whilst gaining extra bass.

[aquapiranha]

You did a great job Steve. They sound superb.

Thanks Ali! Like I said though anyone can do it, it isn't hard really. They look great there in your room, I wish I had have kept them now :lolsign:

[Dominic Harper]

Strange thing is, my missus actualy prefers these to the floor standers I was using before!

http://i990.photobucket.com/albums/af30/hifimaster/hawthorne/DSC01619.jpg

[aquapiranha]

They look lovely Dominic. A bit like the ones I built, nice clean lines. Did you find the bass ok on them? the reason I ask is that I used 2 X 15" Eminence Alphas per side to make up for the lack of a box.
They are Silver Iris drivers? Steve

[John]

Nice work

[Dominic Harper]

Yes they are 10" silver Iris's with matching bass Augies. The bass is incredible, very clean and extended. The bass units are powered with a Rythmik plate amp.
Test tones indicate these things go down to 35 Htz!

[aquapiranha]

Yes they are 10" silver Iris's with matching bass Augies. The bass is incredible, very clean and extended. The bass units are powered with a Rythmik plate amp.
Test tones indicate these things go down to 35 Htz!

Good job. Never measured the others but Ali might have. I drove them in active config with bass driven by two channels of a Sure 2050 Tripath amp and the Visaton B200's the other, via a Rane AC23B X-over. The B200's are fantastic drivers. Might have to have another look at the Silver Iris site.

http://www.hawthorneaudio.com/

[Dominic Harper]

I am seriously thinking of importing some drivers and plate amps from Hawthorne, and making custom OB's with slate baffles.
I have spoken to Darrel at Hawthorne and he is a great guy.

[John]

Yes Darrel a great guy one of the nicest guys you could deal with
The 15" bass drivers go even lower I think slate be great just not sure what the market would be I offered a cheap bespoke service awhile back and no interests

[Dominic Harper]

I agree John. Shame really as they would be a bargain compared to the competition, ie; box speakers.

[John]

Yes it would be a fantastic speaker and would offer crazy value for the performance. Perhaps you could build one for a show and then see if you get a response at the show and then offer it for review to the mags

[wee tee cee]

Tony, you're welcome to come over for a listen at the weekend if you like. I use a pair of Bantam Golds driving the OB's actively using a Behringer DCX2496-

http://img43.imageshack.us/img43/6818/imag0143q.jpg (http://imageshack.us/photo/my-images/43/imag0143q.jpg/)

Ali,
Thanks for the offer,I work shifts and do a lot of weekend work.If its OK ill pm you near my next weekend off.You mentioned the cost of the drivers,is it required to custom make crossovers or can someone sell these.
Regards Tony.

[John]

Ali uses active x over approach

[Spur07]

I am seriously thinking of importing some drivers and plate amps from Hawthorne, and making custom OB's with slate baffles.
I have spoken to Darrel at Hawthorne and he is a great guy.

Go for it Dominic. If I hadn't inadvertently got in to EMI ellipticals I would have followed John down the Hawthorne route - may still do at some point. so much bang for your buck.

[John]

Dominic: Try moving the back plate of the tweeters really improved them if you got the steriling you can reservse it if you do not like with the Silver Iris you have to find a way to remove the cover, makes a big difference in terms of detail and image

[Ali Tait]

Ali,
Thanks for the offer,I work shifts and do a lot of weekend work.If its OK ill pm you near my next weekend off.You mentioned the cost of the drivers,is it required to custom make crossovers or can someone sell these.
Regards Tony.

No worries Tony, let me know. I use a pair of Golds to drive the speakers actively, using a Behringer DCX2496. These can be had on ebay for about £150 secondhand. Sounds great.

[Dominic Harper]

Hi John. It's on my 'to do' list. Will get around to tinkering with them at some point. I just enjoy these speakers so much as they are.
I will at some point design some slate baffles and stand with adjustable tilt and 3 point base. The idea is finished in my head but just need the funds to sort it.

[wee tee cee]

A mountain of information,thanks Gents.
I must admit to not knowing an awful lot about crossovers active or otherwise.
I look forward to hearing Obs but would like to know what it would cost me to build them from scratch,might even have to factor in a saw.
I could purchase drivers/baffle/crossover in instalments....maybe even do a step by step number (if I figure out how to post photos).
I think this could provide an Idiots guide....The path to OB salvation.

[John]

Its not complicated as I said if you go down Ali route then perhap ask Steve to copy his design If you go down the Hawthorne route I send you a link that explains a step by step process that I even I could follow
You probarly get some timber merchants to cut for you or you could hire out or borrow suitable equipment
Equipment you could use electric saw a router and screwdrivers

[Spur07]

if you go down the Hawthorne route you can buy x-overs if required and a basic baffle ready cut, and you'll get all the support you'll need. It'll be just a case of glueing and screwing. If you want to copy a design or make your own there's usually someone at a timber merchants who will gladly cut your wood for cash. For my first baffles I used 3/4" ply - the sheet of timber cost something like £60 and the guy who worked in the timber department cut it up for £20, and that included cutting out the awkward elliptical shapes with a jig. If I need to make tweaks, etc I'll borrow my mates circular saw.