diyAudio Full Range Reference Project

Driver Choice

Hello Guys:
This is just the thread I was hoping would get going. I have a nice little pile of lumber in my shop that is in need of a project. I was planning on doing this very thing myself.
I think the concept of deciding on the the driver is the one that should be concluded first. I think there are three to chose from. The FE103, FE127, RS1197. All are reasonably priced. The reputation of all three is good. There are proven designs as well. They are all reasonably sensitive. It is always possible to have build cabinet designs for all three and have a shoot out. Hmmmmm that might be a good reason for another get together. I already have a few 1197, and a set of FE103A I just need a set or two of Fe127 to get going
 
Unfortunately the 1197s are a challenge to come by for many people unless someone is willing to disperse their stockpile :D .
Have we eliminated the modded TB 881? Kinda sounds like it. That would leave the FE103E and the FE127E. I love the lower Fs of the FE127E so that would be my first choice. I do like the idea of the Solo 103 because it's already out there and is an easy and accessible project for most everyone. So my vote is..
1. FE127E
2. FE103E

:)
 
As a "common to many of us" reference speaker project, I'll definitely participate, but let me just say that my feeling from the other "reference" project, is that we didn't set our goals high enough to get wider involvement.

Altho I like Dave's suggestion of solo or Bi 103's, the idea of just keeping the price low, might produce only average results. When you factor in the effort and expense of bringing the cabinets to finish, the price of the drivers might eventually be forgotten. That said I applaud GM for starting this thread, and everyone for participating.

OK-on to my questions:

Tim, as the cost is about the same, how does the Bi-103 compare to your mini-array 871S ?

As we look at the 167 and 207 or 4 127's their prices compare to the new offerings at Adire and CSS.
What do you guys who've heard them think? Should we be considering the Extremis or CSS XBL, or am I missing the point of this thread?

Are we limiting ourselves to easier-to-build cabs?

What could tip the scales here, a great deal on a group buy? Can anyone get a deal on Fostex in quantity?
 
Good thoughts x. onasis:
I have heard the CSS XBL and was impressed. I was also impressed with the fe127. I think it would be interesting to work up a desgn for the CSS driver as it is new to the market and seems to have a great deal of promise. The Fostex drivers have a proven track record that is very reliable. So do we stick with the known or try the new. Perhaps the group buy price will help to make the final decision.
Perhap we need to keep the prime directive in mind here, we can easily get lost in dreamland and suffer from paralysis by analysis.
So what was the prime directive again? What is the objective of the project. To develop a fullrange reference project for a reasonable price or something like that.
 
Tim, as the cost is about the same, how does the Bi-103 compare to your mini-array 871S ?

I'm not sure which mini-array you're referring to. If it's the one with the 6 W3-871S on top of the 2 W5-704s the price isn't even close. I also don't believe it meets the criteria of this project. If you're referring to the small 4 driver array I scraped that project long ago. That was a pre-Spires design that CSS did a better job with. IMHO, arrays have their place but I would prefer to see this project stay as close to single-point source design as possible to demonstrate the ability of a full-range to deliver an excellent soundstage. If the group wants to do a low-cost line array I can't think of anything much better (price/performance) than the CSS Spires.
 
Timn8ter said:
Unfortunately the 1197s are a challenge to come by for many people unless someone is willing to disperse their stockpile :D .
Have we eliminated the modded TB 881? Kinda sounds like it. That would leave the FE103E and the FE127E. I love the lower Fs of the FE127E so that would be my first choice. I do like the idea of the Solo 103 because it's already out there and is an easy and accessible project for most everyone. So my vote is..
1. FE127E
2. FE103E

:)


Fostex seems to provide a reasonable compromise between cost and performance. In addition, they are popular, well documented by Fostex and others.

If we go bipole, FE103 and FE126/127E would be options to try keep costs down.

Tim, is there a reason you prefer the 127 over the 126?

For a monopole project, we could go for lower costs with the FE126/127E. However, the FE166E and FE206E can also be considered at costs similar to the bipole option.

For projects, I also like the Solo103, however, the woodwork does not look that straight forward.

A slim T-line is always attractive in my mind.

As mentioned previously, the idea of the GM-Voigt looks like a nice project. I like the idea of common wood sizes to simplify the woodwork. The FE127E in a folded voigt may be an option.

Somethings that I would like to see this project have are:

1. Unmodified drivers. Reversable modifications may be okay as they can likely be reproduced well between builders.

2. Try keep total driver costs below about $180US.

3. Relatively simple woodworking so not to scare off potential builders.

4. Low power/tube friendly designs.

Anyway, for the time being, we should concentrate on drivers. My suggestions are (in no order): FE126/127E (bipole?), FE166E, FE206E.

I don't know if Fostex plans to keep the FE103E around.
I prefer the FE166E and FE206E over the FE167E and FE207E.
 
Hello Guys:
Is there a performance diference between the Fe??7 driver and the FE??6 drivers. I thought they were the same except for magnetic shielding.
If that is the case then it does not really matter. I already have a Fe167 project completed so I am leaning toward the FE127 as a mono and a bipole. Both are pretty simple to build and the cost is not too bad.
TQWP or MLTL or folded TQWP all of these work for me.
 
SCD said:
Hello Guys:
Is there a performance diference between the Fe??7 driver and the FE??6 drivers. I thought they were the same except for magnetic shielding.
If that is the case then it does not really matter. I already have a Fe167 project completed so I am leaning toward the FE127 as a mono and a bipole. Both are pretty simple to build and the cost is not too bad.
TQWP or MLTL or folded TQWP all of these work for me.

The Fe??7E driver are sheilded while the FE??6 is not. All of the Fe??7E drivers seem to have a higher Q, which makes them less suitable for a horn.

In my mind,

The 107 FR looks better than the 103

The 126 has rising FR, and less bumps. The 127 has a few more bumps but the FR does not rise, however, the impedence rise is about 4ohm higher

The 166 and 167 look very similar.

The 207 is 1dB less efficient and does not have the HF that the 206 has. A super tweeter may be needed with the 207.

That being said, I prefer the FE??6E, unless several people see the necessity for shielding.

Cheers,
Gio.
 
x. onasis said:
As we look at the 167 and 207 or 4 127's their prices compare to the new offerings at Adire and CSS.
What do you guys who've heard them think? Should we be considering the Extremis or CSS XBL, or am I missing the point of this thread?

My Fostex suggestions are just ideas. The nice thing about Fostex is that it is available in several different countries.

I like the idea of a reference project being feasible for as many people as possible.

Gio.
 
Are we getting closer

Well it looks like we have gone half way arround the block today discussing this one. It seems we are very close to coming up with a driver. I am not sure how long we want to debate the choice of the driver or if there might be anyone else interested in this part of the discussion.
I put forward that we go with the Fe127 and begin discussion about the enclosure.
 
frugal-phile™
Joined 2001
Paid Member
The CSS is a nice driver... a little shy on top... not as tube friendly and quite a bit more $$$ -- it is really more in competition with the Jordan JX92 (giving up some top to get better bottom)

As to Tim's Bi-103s vrs his woofer assisted 871 towers, his Bi-1197s (budget FE103s) cleaned their clock.... the 103s should only be better.

dave
 
planet10 said:
The CSS is a nice driver... a little shy on top... not as tube friendly and quite a bit more $$$ -- it is really more in competition with the Jordan JX92 (giving up some top to get better bottom)

As to Tim's Bi-103s vrs his woofer assisted 871 towers, his Bi-1197s (budget FE103s) cleaned their clock.... the 103s should only be better.

dave

Oh sure, if you like depth and detail :D .
 
FE126E vs FE127E

I also prefer the FE126E/FE127E over the FE103E/FE107E.

I do not have sheilding requirements, so I prefer the FE126E.

Here are links to the 126 and 127 specifications:

http://www.fostexinternational.com/docs/speaker_comp/pdf/fe126e.pdf
http://www.fostexinternational.com/docs/speaker_comp/pdf/fe127erev2.pdf

Quick Summary:

FE126E
Fs=70Hz, Re=6.9, Qts=0.25, SPL=93dB


FE127E
Fs=70.4, Re=6.5, Qts=0.43, SPL=91dB

I like the extra efficiency of the 126 which is good for those who may want to use a tube amp. The 127 is pretty flat to 6k and then has a couple of bumps. The 126 does not have big bumps, but shows increasing SPL with increasing frequency. Does anyone think that the 126 may be a tad bright? The HF response looks good on both drivers.

My vote is for the 126, unless people think it may be on the bright side.

Regards,
Gio.