Bryn Chang

[oceancity]

My first post. About a year ago I became fascinated with the idea of a single driver. I read a little and bought a pair of Fostex FE83E. I downloaded WinISD and began work, eventually arriving at an enclosure. I built the boxes, mounted the drivers and was nothing short of stunned by the clarity, fidelity and sound stage of these little geezers. Hooked. More reading of forums way into the night and early morning while a stream of elegant piano trios, sting quartets, guitar concertos, piano sonatas accompanied me, courtesy of the 83s. I bought a pair of FE126E and decided on the Bryn Chang.My local timber yard has the ply cut. I pick it up tomorrow. And now, I need a little help.Note 3 on the Bryn drawing. How do I work out the sizes of the stepped strips if I decide to go that way. If I decide to go for the single piece deflector, will the void behind it need to be filled with something of substance and weight? Thanks for all the info that I've already used. I think I've walked into what might become a lifelong pursuit......best wishes to all....Pete

 

[planet10]

If you have the drawings it is pretty easy to figure the steps,,, i'm crazy busy right now, but poke me if i don't generate that info... the basic premise is that each piece is of a length where the middle (thickness dimension) of the piece reaches the line defined by the outer edge of the 1 piece deflector.

If you use one-piece then it is best filled.

dave

 

[chrisb]

My first post. About a year ago I became fascinated with the idea of a single driver. I read a little and bought a pair of Fostex FE83E. I downloaded WinISD and began work, eventually arriving at an enclosure. I built the boxes, mounted the drivers and was nothing short of stunned by the clarity, fidelity and sound stage of these little geezers. Hooked. More reading of forums way into the night and early morning while a stream of elegant piano trios, sting quartets, guitar concertos, piano sonatas accompanied me, courtesy of the 83s. I bought a pair of FE126E and decided on the Bryn Chang.My local timber yard has the ply cut. I pick it up tomorrow. And now, I need a little help.Note 3 on the Bryn drawing. How do I work out the sizes of the stepped strips if I decide to go that way. If I decide to go for the single piece deflector, will the void behind it need to be filled with something of substance and weight? Thanks for all the info that I've already used. I think I've walked into what might become a lifelong pursuit......best wishes to all....Pete

Pete:

The single deflector panel is much simpler to build, and far more economical on materials, but you'd definitely want to load that cavity with some type of ballast. Sand or shot fill will certainly work, but makes the box quite heavy to move. You could try dry kitty litter.


FWIW, I found the FE126 more than a bit thin on the bottom, and with very "in your face" forward presentation in this cabinet without some series R. IIRC, I settled on 3ohms, but this is a balancing act wherein the output impedance of the amp will be part of the equation.

Eventually, I found that I vastly preferred the FE127 in this box - there are several designs of Scott's in which the FE126 absolutely excels, but for me, Brynn is not at the top of that list.

of course YMMV, and all that

 

[oceancity]

Thanks, Dave and Chrisb...I'll go with the one piece and try kitty litter.
"there are several designs of Scott's in which the FE126 absolutely excels," Chris, which are these?
I must have missed them in my research.
I'd like to have a look and consider, maybe buy the 127s and use in the Bryn.

 

[Scottmoose]

Just to point out, Bryn was designed for the 127, not the 126. As Chris points out, the 126 can be used, but it needs some correction & won't have quite the same performance.

 

[oceancity]

Thanks for the input, Scotmoose. I'm OK about resistors,not a purist about much that I can think of, gave up the idea of perfection a long time ago.I am still stunned by the little 83 and I can't see why I'd be disappointed with the Bryn.
I should be able to start assembly on the weekend.

 

[chrisb]

Thanks, Dave and Chrisb...I'll go with the one piece and try kitty litter.
"there are several designs of Scott's in which the FE126 absolutely excels," Chris, which are these?
I must have missed them in my research.
I'd like to have a look and consider, maybe buy the 127s and use in the Bryn.

Saburo, Mikasa & commercial variants for Jeff at CarderSound, including a new single mouth design named Nina.

If you have the material already cut for Bryn, and budget to allow for a second project with the 126s, I'd highly recommend the 127s for the Brynn.

FWIW, I've found the better 126 designs (particularly those with rear mouths and/or supra baffles) more well suited to larger rooms - the heightened dynamics and forward presentation from upper midrange have been overpowering in my small room (effective listening area 8.5ft wide x 15ft, with seating distance of approx 10ft)

OTOH, a much wider range of 127 designs, including several of Dave's Fonken series, Mileva or Scott's Brynn have been far better matched to this moderate space.

No, I don't think you'd be disappointed with the Brynn

 

[oceancity]

I did look at the Mikasa and Saburo and it was the review attached to the Sab that convinced me of the merits of the 126. That bloke sure can write.I then went looking for something that my limited manual skills could deal with. I think the size of the Sabs scared me a bit even though it's all straight and no tricky angles.
I had forgotten the reasoning that went on until I looked at the Spawn family again.I was impressed with the graph attached to the Bryn. Still am. Impressed by it's simplicity of build. Budgetry constaints played a part too.
So here I go. The timber has been cut and I'll start building in the next day or two.
My room is 10 feet by 14. So this is going to be a trifle amusing me thinks.
The 83s already fill the room. BTW. I'm using a Sonic Tamp and an old Yamaha sub fills in the bottom end for me, crossed at about 140Hz if you can believe the Yammy manual.
Another question...BSC? or just the R?

 

[chrisb]

I did look at the Mikasa and Saburo and it was the review attached to the Sab that convinced me of the merits of the 126. That bloke sure can write.I then went looking for something that my limited manual skills could deal with. I think the size of the Sabs scared me a bit even though it's all straight and no tricky angles.
I had forgotten the reasoning that went on until I looked at the Spawn family again.I was impressed with the graph attached to the Bryn. Still am. Impressed by it's simplicity of build. Budgetry constaints played a part too.
So here I go. The timber has been cut and I'll start building in the next day or two.
My room is 10 feet by 14. So this is going to be a trifle amusing me thinks.
The 83s already fill the room. BTW. I'm using a Sonic Tamp and an old Yamaha sub fills in the bottom end for me, crossed at about 140Hz if you can believe the Yammy manual.
Another question...BSC? or just the R?

The Brynn has a fairly wide effective baffle area, certainly compared to many other popular DIY (non OB/combo) designs for the 126E. Since you have a sub and fairly small room, I'd be inclined to try just the series R. For the amount of power the driver will actually be consuming, you could probably get away with 5 watt 8ohm L pad attenuator to dial in the value that works best with this combo.

Of course I'd be remiss in not suggesting again that future budget and interest permitting, you try the FE127E in these boxes, and graduate to another project for the FE126E. Another driver that works quite well for me in Brynn is the Hemp Acoustics FR4.5 - too bad about supply issues from this "company".

 

[oceancity]

Finally started on the Bryn. May be another week or two to having a listen. Here's a photo.

 

[oceancity]

Many, many thanks to Dave, Scott and Chris. The Bryn Changs are finished and working with the 126s and a series 4.7ohm.I am very happy with them. . I am grateful to you blokes for being and doing. It gives me great pleasure to hear my CDs in a way I've never before heard. My life is a good measure better. My woodworking skills have improved, they are still primitive and my tools are limited but I now have the confidence to try another project. Finishing is a separate art form and I've settled for matt black paint.
I filled the void with dry kitty litter, as suggested by Chris. The top, bottom and one side in the chamber are damped with a bitumen based product. I haven't yet braced them. I just couldn't wait. I had to have a listen. Duct seal still to do too.
I've gotten used to the Fostex sound with the little 83s but this combination is a huge step up.
I had expected less bottom end. I'm happy.It's there. The mids and highs are not harsh. Quite smooth. Plenty of detail. I'm listening to the new BB King now. During the afternoon, Bach violin concertos.Oscar Peterson, it's all good. There's about 60 or more hrs on the drivers. I had them in rough boxes for the past few days.
The state of the A$ is such that it will be a while before I can get a pair of 127s, but they are on the list and in the meantime I'll figure out which enclosure for the 126s. I cant see any way of getting the Hemp speakers that Chris referred to. If you can't get them where you are, there's no chance in OZ. I'm happy using Fostex for now ..........THANKS AGAIN.
Pete