diyAudio Full Range Reference Project

[gmilitano]

Re: More lower mids

Granted they only have about 50 hours on them, and they already sound better than they did at first, but I am not optimistic that they will eventually fill the room a lot better.

Hi George,

Give it time. I broke the FE127E in for about 100 hours. At that point, the mids and highs were pretty good and have not changed much. However, since then I have been able to drop the crossover point from about 100Hz to 80Hz. These guys need major hours before they fully break in.

Also, since you are monopole, the problem may not be lack of bass, but rather that they are to bright as a result of baffle step.

Give this a read:

http://www.quarter-wave.com/General/BSC_Sizing.pdf

Moving the speakers towards a wall can also help reduce baffle step.

 

[stelleg151]

Yeah I have been considering putting in a BSC, I think I will try that, although I was hesitant to because the SI was rumored to sound much better without any circuits in between it and the drivers, but perhaps I will tinker.

Thanks dave,
George

 

[rabbitz]

I found BSC was a must with a monopole FE127E and the amount required varied from room to room even though they were similar amounts from the back wall.

On this FE127E there is a BSC table which only applies for the 200mm wide baffle. There's a great BSC spreadsheet to calculate these components on the quarter-wave site mentioned in GG's post.

 

[preiter]

I had to add BSC to my FE127 monopole as well. You can avoid it by building a bipole, the the BSC circuit is a lot cheaper than two more drivers.

 

[stelleg151]

I had to add BSC to my FE127 monopole as well. You can avoid it by building a bipole, the the BSC circuit is a lot cheaper than two more drivers.

Most definately.

Also, I dont have the drivers flush with the face of the box, does that matter at all?

 

[planet10]

Also, I dont have the drivers flush with the face of the box, does that matter at all?

Everything matters, but the 126 & 127 are most often just mounted. The shallowness of the bezel & its shape tend to minimize any issues. If you are worried, just build up the baffle with some felt.

dave

 

[gychang]

Hey guys,

Wow, long thread! - After learning about and deciding to buy myself a T-amp to play with and mod (I'm a little late to the party - this is all new to me), I wanted to build myself a decent pair of simple, full range speakers to be able to enjoy music with.

After deciding to use either a Fostex FE207 or FE127, I stumbled across this thread....

Well, 69 pages later - I have ordered a pair of 127's, my T-amp, and some assorted caps - and I am juiced to get started building a pair of the folded monopole design!

Thanks to you guys for starting the thread and developing the designs - I likely wouldn't even be giving this a try if it wasn't for all of your work!

Now I just want the stuff to get here, so I can get started!!

I am a owner of a unmodified sonic T-amp, let me know how things turn out...

gychang

 

[stelleg151]

I am a owner of a unmodified sonic T-amp, let me know how things turn out...

gychang

I have that setup and I love it. Been using electronic BSC, and they work great.

 

[Ray Collins]

I need a pair of bookshelf speakers to actually use on the bookshelves in my kitchen. Would the Fonken, miniOnken or rabbitz's monopole work?
Thanks,

Ray

 

[planet10]

Sure... the miniOnken with the FR125 would definitly need damped ports to not be way bass heavy.

dave

 

[GM]

Greets!

More than likely, open back will be sufficient with the FR125S since you'll get strong cavity resonances.

GM

 

[Ray Collins]

GM,
If your input was for me I missed the point; please explain.

Ray

 

[GM]

Greets!

Make a box with no back, IOW a dipole, and if there's too much mids/HF reflections either place a decorative potholder behind it or lightly stuff the rear of the box.

GM

 

[Ray Collins]

GM,
Uhhhh.....still new to much of this....but.....did my leg just come off in your hand?!

Ray

 

[GM]

??

 

[Ray Collins]

Were you pulling my leg (kidding me) about no back and the pot holder?

 

[planet10]

I wouldn't use a pot holder, but i don't think he was kidding

dave

 

[Timn8ter]

Sounds reasonable to me. There are published plans for a FR125S dipole although this one is probably larger than what you have in mind.
http://creativesound.ca/pdf/EasyPole.pdf

 

[Ray Collins]

Appears that the Yolk is on me.....too much thinking Inside the Box?!

 

[GM]

Were you pulling my leg (kidding me) about no back and the pot holder?

Greets!

Nope, I never 'kid' about speaker design advice unless we're all just being 'silly' for whatever reason. This doesn't mean to imply that it's always good advice though, all knowing I'm not, I just come up with the best I can at that moment.

GM