O.B. Newbie help?

Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
Hello everyone. So I am looking to do a small dipole O.B. For my family for the family T.V. Room. I didn't want to to buy a sound bar and knowing I have a lot of extra wood around that's taking up some space in the garage. I wanted to build a simple O.B. So what program do I need to get started? So The design is after the no more O.B. Dipole from tekton speakers with 2 fostex drivers. ( not trying to copy but, was told they don't offer it anymore? So Please help I need it. Thanks Jeff

P.S. There's a picture of the design I am thinking of? Cheers Jeff
 

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guangui

Member
2013-02-12 12:21 pm
Hello everyone. So I am looking to do a small dipole O.B. For my family for the family T.V. Room. I didn't want to to buy a sound bar and knowing I have a lot of extra wood around that's taking up some space in the garage. I wanted to build a simple O.B. So what program do I need to get started? So The design is after the no more O.B. Dipole from tekton speakers with 2 fostex drivers. ( not trying to copy but, was told they don't offer it anymore? So Please help I need it. Thanks Jeff

P.S. There's a picture of the design I am thinking of? Cheers Jeff

They came up with a replacement, but it is a tower and expensive compared to what you want to do. I had the same issue as you, so I designed one and built it, I am extremely happy with the end result and sound much, much, much better than anticipated. Here is a video of my project. I posted information here. Feel free to ask any questions.
 
You beat me to it guagui, nice design, I hadn't seen it before :)

Hi Mr Jeff 7,

Interesting design, I've looked at it quite a bit. Opinions vary here on it's effectiveness.

Being an OB it probably sounds best well away from the front wall but given some of the cancellation effects going on here I'm not so sure, you may have more wiggle room?

Winisd is a good program for figuring out enclosure volume, it's widely used here.

LinearTeam

A lot of folk use the Edge for the OB potion of their speaker.

Home of the Edge

I haven't played with this much myself.

If you're not 100% set on OB don't discount a bipolar-castle design here. Better bass, more power handling and probably easier to integrate into your room for the same amount of drive units you would use in the tekton design.

http://www.diyaudio.com/forums/full-range/270528-castle-microtower-build.html

Here's a fostex sealed bipole using similar driver to the teckton, you'd want a sub with this or else remodel the design with winisd to get a port loaded enclosure for more bass. This would be best away from the wall too.

DIY Sealed Bipole Speaker Project with Fostex FE127E Driver
 

guangui

Member
2013-02-12 12:21 pm
Ewollowe, thanks! They sound really good, I couldn't be happier with my driver selection, which blend aesthetics with sound quality; that was the intended result. There are mixed feelings regarding the cancellation theory behind the Tekton OB. I all honesty, I don't fully understand it, and I have not heard them, so I won't comment if good or bad. I believe fellow member Poultrygeist has a pair.

I had heard many good things of the Mark Audio CHR-70.3A, and of the HiVi MXN drivers, as the M4N is the one used for the Overnite Sensation Kit, which is highly regarded. The M5N has good bass extension, but I was more amazed as to how good they sound. I crossed at 520 Hz, so not using the HiVi in all their potential. At sometime I will use them in a 2 or 3 way tower design. The amount of detail from this speaker design is great, I have rediscovered many recordings. Being used bi-amped with an active crossover, but I already received the necessary components to build a 2nd Order LR XO, and adjustable L-Pad.

I am pretty sure the design can be made better using other drivers or configurations, but you should try to build these; you will not regret it.
 
Your's is more of a small FAST (Full-range and Sub-woofer Technology) design, a nice one too.

Unless Mr Jeff 7 is completely sold on the tekton design I'd go with yours instead.

I have some HiVi drivers somewhere too, think they're 4"? I'll get around to putting them in something but I have to finish another project first. Now if it wasn't 38C outside today I'd probably get more done :p
 

guangui

Member
2013-02-12 12:21 pm
Your's is more of a small FAST (Full-range and Sub-woofer Technology) design, a nice one too.

Unless Mr Jeff 7 is completely sold on the tekton design I'd go with yours instead.

I have some HiVi drivers somewhere too, think they're 4"? I'll get around to putting them in something but I have to finish another project first. Now if it wasn't 38C outside today I'd probably get more done :p

Yes, they are "FAST", but with the baffle being sort of narrow for the FR driver below 500 Hz you start to notice the SQ go downhill, so cannot go down to 200 Hz...I tried crossing them at different frequencies starting from 1500 Hz down. As I went down on the Hz scale the sound opened up. Came to the conclusion that at 520 Hz was the best sound, which was pretty close to my suggested 600 Hz when running simulations on design software.

38C is summertime here, actually wintertime is 30C to 33C, I work all the time outside on 43C (33C, plus humidity factor of 90%). Just keep plenty of water to drink, work area with a roof or cover, and a large pedestal fan always helps. Today (winter), it was 29C with 87% humidity, which translates to 36C; I almost went snow skiing!!!
 
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Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
They came up with a replacement, but it is a tower and expensive compared to what you want to do. I had the same issue as you, so I designed one and built it, I am extremely happy with the end result and sound much, much, much better than anticipated. Here is a video of my project. I posted information here. Feel free to ask any questions.

Wow. The speakers look amazing. I like the HiVi drivers but, not too hyped about the mark audio drivers. ( Having a pair in the past). I love the design of the cabinet. I think you did a great job with your speakers. Thanks for posting your project. I will be showing my wife so she gets the idea of what I want to build? Would you mind helping me? Or giving me advise? I was thinking of using a 3 inch driver with a 5 1/2 driver? Both are made from the same cone Material and company. Let me know? Thanks Jeff
 

Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
Your's is more of a small FAST (Full-range and Sub-woofer Technology) design, a nice one too.

Unless Mr Jeff 7 is completely sold on the tekton design I'd go with yours instead. ( I am not sold on the tekton design I just liked the whole package ). I am open to ideas? Jeff

I have some HiVi drivers somewhere too, think they're 4"? I'll get around to putting them in something but I have to finish another project first. Now if it wasn't 38C outside today I'd probably get more done :p
 

guangui

Member
2013-02-12 12:21 pm
Wow. The speakers look amazing. I like the HiVi drivers but, not too hyped about the mark audio drivers. ( Having a pair in the past). I love the design of the cabinet. I think you did a great job with your speakers. Thanks for posting your project. I will be showing my wife so she gets the idea of what I want to build? Would you mind helping me? Or giving me advise? I was thinking of using a 3 inch driver with a 5 1/2 driver? Both are made from the same cone Material and company. Let me know? Thanks Jeff

Sure, glad to help...I actually find the MA's in the OB configuration really good, but I'm sure there are better. 3" + 5.25" is very similar to what I have, and can tell you that they easily fill my current 18' wide x 12' deep listening room. My wife likes the look, the reason why I paired both drivers was the matching color, then I started to read about them, and to me they were a no-brainer, as they had the price/performance/looks I was looking for. What drivers do you have in mind?

I find the mid and highs of the MA CHR very good, including off-axis performance. I have heard that they are lacking on the bottom end, but in this design I don't have to worry about that.
 
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Yes, they are "FAST", but with the baffle being sort of narrow for the FR driver below 500 Hz you start to notice the SQ go downhill, so cannot go down to 200 Hz...I tried crossing them at different frequencies starting from 1500 Hz down. As I went down on the Hz scale the sound opened up. Came to the conclusion that at 520 Hz was the best sound, which was pretty close to my suggested 600 Hz when running simulations on design software.

38C is summertime here, actually wintertime is 30C to 33C, I work all the time outside on 43C (33C, plus humidity factor of 90%). Just keep plenty of water to drink, work area with a roof or cover, and a large pedestal fan always helps. Today (winter), it was 29C with 87% humidity, which translates to 36C; I almost went snow skiing!!!

I have no problem in the heat, I work all day in it but I'd rather not on my days off :) I'm still contemplating it though. Probably doesn't help that I'm Irish :p
 

Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
Sure, glad to help...I actually find the MA's in the OB configuration really good, but I'm sure there are better. 3" + 5.25" is very similar to what I have, and can tell you that they easily fill my current 18' wide x 12' deep listening room. My wife likes the look, the reason why I paired both drivers was the matching color, then I started to read about them, and to me they were a no-brainer, as they had the price/performance/looks I was looking for. What drivers do you have in mind?

I find the mid and highs of the MA CHR very good, including off-axis performance. I have heard that they are lacking on the bottom end, but in this design I don't have to worry about that.[/QUOTE

Thanks for the speedy reply. I am looking at the Tang Band W3-926SD poly fullrange and the Tang Band W5-704D poly mid bass fullrange woofer. I am going passive on the cross over do to funds. i hope this helps ? Jeff
 

Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
You beat me to it guagui, nice design, I hadn't seen it before :)

Hi Mr Jeff 7,

Interesting design, I've looked at it quite a bit. Opinions vary here on it's effectiveness.

Being an OB it probably sounds best well away from the front wall but given some of the cancellation effects going on here I'm not so sure, you may have more wiggle room?

Winisd is a good program for figuring out enclosure volume, it's widely used here.

LinearTeam

A lot of folk use the Edge for the OB potion of their speaker.

Home of the Edge

I haven't played with this much myself.

If you're not 100% set on OB don't discount a bipolar-castle design here. Better bass, more power handling and probably easier to integrate into your room for the same amount of drive units you would use in the tekton design.

http://www.diyaudio.com/forums/full-range/270528-castle-microtower-build.html

Here's a fostex sealed bipole using similar driver to the teckton, you'd want a sub with this or else remodel the design with winisd to get a port loaded enclosure for more bass. This would be best away from the wall too.

DIY Sealed Bipole Speaker Project with Fostex FE127E Driver


So I looked at the different projects you posted and I like the castles a lot but, it has to be small un-less the wife tells me different ? So a smaller stand mount or book shelf will have to do. The castles look like something I could build for a room I could put them in to listen too in the future. Thanks for all your help. Jeff
 

guangui

Member
2013-02-12 12:21 pm
I like that TB W3-926SD, good specs and the reviews advise that it has very good high freq. performance, which you need in this design. And the W5-704D is a very nice woofer with great specs that can go up to 9K Hz, which gives you a lot of leeway. Very similar to the HiVi M5N in the freq. range. Both drivers have a very similar SPL 88dB for the woofer, and 87dB for the full range, which depending on your room and amplification you might not need an L-Pad; we can get close to know via simulations. It is an 8 Ohms design, and should be an easy drive for any receiver/amp.

It is my opinion that going with a larger vented enclosure (see enclosed dwg) than the one recommended by PE will yield an f3 of 60Hz without putting much stress on the woofer. As for the baffle, depends on how big you want to go, personally I have found that 16" high is as large as a bookshelf speaker I like, but that is me. Don't know if you are planning on making the cabinets, but Dayton's 0.38 cu.ft. enclosures are ideal for this project. Line them with 3/8" thk. upholstery wool to dampen and use some polyfill (or similar) and you should get great sound; others might chime in on better solutions. The enclosure is 14" tall, so, I would build a taller baffle, as to leave an OB area for the FR driver. Overall outside dia. for the FR driver is 3.19", so no less of 4" tall OB area is needed. Width would be the same as the enclosure, which is 8" wide. Remember, these measurements are using a pre-made enclosure. If you are building your own enclosure you might play with measurements as to get an enclosure that fits your space.

So, our front baffle will be 20" tall x 8" wide; I recommend 3/4" thk. wood to add rigidity and be able to countersink the drivers.

Ran some sims, and your XO point seems to be around 600 Hz. You can go further down, but you would have to check at which point you should go with a Baffle Step Comp Circuit. I didn't use BSC on mine, don't need it at the point I'm crossing. In my case, I did need to L-Pad the FR drivers about -4dB.

SPL response for both drivers is about the same, well inside the 3dB range, so no problems there. There are some bumps that get close to 4dB, personally, I wouldn't worry much, but if you want to control them to below 3dB you will have to do a circuit to do so. I highly recommend a bi-amp terminal(s) as to in the future play with MiniDSP or active XO. Simulations are based on the recommended enclosure/baffle, and the drivers TS Parameters, it doesn't take in consideration room acoustics; independent measurements at your listening room with drivers running full range might be needed to further enhance/fine tune the XO circuit. Actually, I ran mine full range for quite awhile while deciding if going passive or active. I decided active as to fine tune with it, then build passive based on my active set parameters, which at this time is 520Hz/Inverted Phase on one driver/-4dB gain on FR driver. Active is 24dB Behringer, next time I will just get a MiniDSP.

If you want to go active, a MiniDSP will run you around $110.00, and building a 4-Channel Class D 50WPC (TPA3116d2) will run you about $75.00.
 

guangui

Member
2013-02-12 12:21 pm
I'm just saying...my partner has no problem with me putting moderately large speakers in the lounge but only after I threatened her with humungous ones :D

LOL...That is a good one...Even if the components don't work, just build a large cardboard OB with 15" woofers, 8" Mid, and large Horn Tweeter, and tell her it is just a model to see how you accommodate them prior to building, and she will let you build whatever you want, as long as it is not the big a$$ ugly OB's.
 
LOL...That is a good one...Even if the components don't work, just build a large cardboard OB with 15" woofers, 8" Mid, and large Horn Tweeter, and tell her it is just a model to see how you accommodate them prior to building, and she will let you build whatever you want, as long as it is not the big a$$ ugly OB's.

These monstrosities are currently sitting in my lounge :) She's a tolerant woman :)
 

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Mr Jeff 7

Disabled Account
2015-11-14 6:10 pm
Michigan
Hey Jeff,

Well, a floor stander like the castle build just means you don't have to buy stands........maybe she who must be obeyed might like that point? :D


Very funny (lol) that gave me a good laugh. So I do have my own listening room and can go as big as the sky but, for my wife she's into plug and play these days. Not so cool for me. I will show her the picture and go from there. Thanks Jeff