FE127E for front soundstage in 5.1 system

Status
Not open for further replies.
Jump to Latest
B

big_kahunah

Member
Joined 2005
#1
After doing some reading I'm considering using the FE127E for a front soundstage in a 5.1 surround sound system.

I'm think about using the straight bipole plan here:
http://www.diyaudio.com/forums/showthread.php?postid=843952#post843952
for the left and right channels

and a simple sealed enclosure for the center channel.

Originally I had planned to reuse some Infinity 4" speakers (REF4002i) in a MLTL for the left and right channels and finding another driver for the center channel. Is this a good option? I have read of problems with mismatching speakers.

As this will be used for both movies and music, a high level of volume is essential. Bass is not too much of a concern because I will supplement with a subwoofer below 100hz. For my rear stage I will be using to RLH that I have already built.

Will this work well for my application? Will it provide enough volume while maintaining the quality?
 
#3
For home theater the TB’s seem to work better IMO. I have both the 127e and the TB Bamboo. The TB is slightly less detailed and less efficient. They are both very clear sounding drivers. The TB’s handle explosions and rumbling from movies better than the Fostex (which is an amazing driver for music only… last night Eva Cassidy and Holly Cole were in my living room for about an hour)… then when the kiddies came home Peter Parker was learning how to throw webs from his wrists in Spiderman – the TB Bamboos have more authority in the mid/bass. I think the TB Bamboo’s are the perfect home theater driver. For home theater I feel the TB Bamboo’s are the way to go. They are great for music too. (But Eva and Holly sound more ‘there’ thru the fostex 127e).

Peace,
Godzilla
 
#5
The Fostex 127e and the TB Bamboo are IMO the best drivers you can buy for around $40. There are no losers here, only preferences. The 127e will work great for HT, I just prefer the TB Bamboo for HT… but I prefer the Fostex for music. I’m glad I have both. I add a piezo on the back of the cabinet for the Bamboos and play the 127e straight. One pair’s in the den, the other in the living room. I’m doubly blessed!

Think about it, which drivers are better than either one of these for around $40?

http://www.zillaspeak.com/fostex127eSSB.asp

http://www.zillaspeak.com/Bamboo.asp


Godzilla
 
#6
Godzilla, I was looking at the TB`s in the new Parts Expess catalog and I want to try a pair in an Onken enclosure. So far my expirience with fullrange drivers is limited to mainly Fostex and some old EV`s and Goodmans. I need to get around a little more.
 
#7
Yup… and I want Hemps, Supravox, Jordan, Lowther… to name a few!

TB’s are a little laid back, less detailed (but very clear sounding) and less efficient than Fostex (in general). They are both quality drivers… made well… look good.

I think the 127e and the Bamboo are good alternatives to more typical small two way speakers available. Lack of a crossover in any critical region is the key to their coherent, seamless, natural sound quality. I can’t see spending double on a comparable sounding Vifa/Morel/Audax system and getting worse sound.
 
#8
Thanks for the rundown. The side-by-side comparison is very helpful.

I just realized that I'm not entirely sure what kind of enclosure to use for the center channel. I'm thinking a vented enclosure may work well, but sealed is also an option. What would work better? I've read the TB's perform well in many enclosures.

Also, one thing to note is that this setup is not a true fullrange. I will have a sub crossed over around 80hz. Music is also important to me, but this will be mostly for HT applications.
 
#9
I have modeled the TB driver in mathcad using a bipole MLTL configuration. Could you guys take a look and offer any suggestions you might have? I think playing around with the stuffing some could help smooth the higher frequencies a little bit more...

I have attached an html version of my modelling. The worksheet is too big to be attached.
 

Attachments

#13
Oh I apologize. It worked on my computer, but apparently I forgot to attach the images with the file. however with the images I cannot get the file to be small enough to be uploaded to the forum. So here is the information that I have inputted into the sheet:

fd=75 hz
re= 6.8/2 ohms
lvc= .01 mH
Bl= 4.8 N/A
Sd= 2*.0057m^2
Vad=2*5.99 L
Qed=.48
Qmd=1.5

L=35 in
position = .5
So= 48 in^2
Sl= 48 in^2
Density = .5 lb/ft
rport= 1.5in
lport= 3 in

This is supposed to be a bipole MLTL so that is why some of the values are doubled or halved.

and stelleg151, doesn't the fostex have a very limited xmax (.35mm). It seems to me that even though it is more efficient it may not be able to handle enough power to bring it to appropriate spl levels.
 
#14
Frequency Response from mathcad
 

Attachments

  • freq-resp.jpg
    freq-resp.jpg
    60 KB · Views: 161
#17
Should I be worried about the ripples in the higher frequencies?

also, it would be nice to have dimensions that lend themselves to construction with pre-cut shelving. I have a table saw, but would like to simplify the construction some. My last project was two RLH and that took longer than I wanted, due to all the cuts.
 
#18
big_kahunah said:
Should I be worried about the ripples in the higher frequencies?
Click to expand...

Only if you forget the stuffing.

also, it would be nice to have dimensions that lend themselves to construction with pre-cut shelving. I have a table saw, but would like to simplify the construction some. My last project was two RLH and that took longer than I wanted, due to all the cuts.
Click to expand...

That shouldn't be a problem if you can get 36" long shelving.

Jeff
 
Status
Not open for further replies.
Top Bottom