www - the w winter work, a Fostex FF125wKeN fullrange project

[Johan]

Thanks Steve. It actually came out better than I hoped for.

Today I put them in temporary use at the main system:



Regarding the finish I haven't decided yet. I like the very light almost white colour of the WL70 on the photo. It is finished in ash veneer and then treated with soap flakes. The speakers now have a very similar colour and look quite good. But unfinished they wont keep that colour very long., so I have to do something. The look of the fresh and newly sanded birch ply is very nice, but as soon as any sort of oil product gets near them, I think they change to a much too dark and yellow tone.

When I started the speaker build I thought of perhaps veneering them in ash also. I fear however that the chamfers and the port openings will complicate that a lot. The visible ply layers at the chamfers give the boxes a nice touch. Normally I don't like to see the ply layers, but here it looks good I think.

I have made some experiments on scrap ply pieces with thin white stain oil with wax oil on top. I am reluctant to the result, it is not exactly what I want. Perhaps I will do the soap flake thing on the speakers also.

[willbewill]

You could lime them?

http://www.bozzle.com/id_limingwood.html

http://www.wood-finishes-direct.com/product/liming-wax

[autobayer]

Hi Johan.
Your woodwork is - again - outstanding and I´m sure, the finish will be as well.
But man: HOW DO THEY SOUND ?
Cheers
Chris

[Johan]

The first impressions are ready. I am not very used to put words on these things, let me try anyway.

The overall sound is very nice. All instruments are clear and natural. There are lots of details. Vocals, guitar and piano are very good. There lacks a bit of bass, but what is there is detailed. The midrange I like very much and the treble is good.

They seem very direct, perhaps fast is a word to describe this. Attachs are very distinct, not smeared in time.

I have noticed more guitar and song tracks than I knew of on some songs. I guess that is a result from good timing and the midrange and treble capabilites from the speaker.

My JBL E80 floorstanders have more bass, but also more muddiness. They sound like if a thick carpet is hanging in front of them.

My wife almost directly said the Fonkens are good. After todays A/B testing, she now says the Fonkens should stay. She thinks they sound much better. At first, a bit direct and screamy, but then she likes them much more. She likes the details and says that they are not boomy.

The Fonkens sound really good already. From what I have heard playing time will improve them. Perhaps I wont even feel the need for that bass.

Thanks for the lime tip Malcolm! That may be an idea also. It seems like a variant of the white oil and wax I have tried.

[sukram]

Hallo Johan,

if it is possible you should change the flax damping and use wool instead.
Years ago I tried flax as damping material but it seems that it sucks the bass out of the music and used wool instead.
The speakers will need a few hundred hours of breaking in. I used FE103 and they improved even after 500 hours.

 A great build, fantastic woodworking!


Cheers
Markus

[autobayer]

Thanks Johan,
they must stay 
I can assure you, that with all full range drivers play-in-time can reach about a year.
And I´m not jokin.
My latest drivers (Triax with a classic stiff accordion surround) now have about a year on their back and they really started to sing about 6 months ago and after 9 months they really opened up.
Since you both like them already, this will be a fantastic journey - and you will maybe surprised of the effect in time.
Cheers
Chris

[ropie]

Great work, Johan!

[Johan]

Thanks all for the kind words!

The infinte play in time you all claim has been noted. I will try not to listen to carefully now then, just wait to later.

if it is possible you should change the flax damping and use wool instead.
Years ago I tried flax as damping material but it seems that it sucks the bass out of the music and used wool instead.

Ist es wirklich so Markus? 

Do you think it's that bad?

I looked around for an alternative to the recommended recycled denim isolation and found this ecological flax thermal and sound isolation and think it seems ok, actually. I have now looked a bit more and I have found references to a test method EN ISO 354:2003 "Acoustic measurement of sound absorption in a reverberating room". Here's a test result for 50 mm flax stuffing:



From the graph it doesn't look to dampen the bass very much. The dampening increases with the frequency. I think the graph looks similar for other materials also, but I may be wrong.

[autobayer]

Johan.
All the "fine ears" I know use sheep wool 
Cheers
Chris

[fetteler]

Johan,
I like your graph and yes, other damping materials  have their greatest effect at high frequencies too. Isn't the purpose of the damping to limit standing waves in the enclosure? The real bass frequencies have a wavelength so large that they will hardly notice a few centimetres of damping - whichever material is used.  The damping will however be extremely effective in limiting standing waves and the associated irregularities in frequency response from the lower mid-range upwards.

For what it's worth, I found these graphs of two different wool based sound insulation materials and they show very similat characteristics to your flax although the absolute attenuations per unit thickness may differ of course....






I personally would not get hung up on this point and would get on with enjoying listening to what you have made.


Cheers,
Steve.

[sukram]

The infinte play in time you all claim has been noted. I will try not to listen to carefully now then, just wait to later.
Ist es wirklich so Markus? 

Do you think it's that bad?

Hello Johann,
unfortunately it seems that flax is not really good as damping material.
I had the same graph and was very enthusiastic  about using it. I used it in a Le audiophile Petite box with Fe 103 but it was extrem awful no bass and almost lifeless. I used the normal isolating material (30mm sliced in pieces of 15 mm) not the felt  material which you used.
After that disaster i used woolfelt and it was a great improvement. Later I tried to only one small sheet of flax under the lid and the rest woolfelt but that was as bad as complete flax.
I used a handful of flax stuffing and put it in other speakers only to find out that it was not good.
Also using it for room damping it was not very successful the only good application was using it behind the speakers. Using it on the sidewalls or behind the listening position sucked the life out of the music.

[fetteler]

I notice on the Planet 10 site that the speaker's only supposed to go down to 60Hz or so. Mind you, the whole site was peppered with graphs which had no title or labels on the axes! Grrrrrrrrr!!!!! What's the point of that?

Maybe everything is as it should be?

Cheers,
Steve.

[Johan]

I see what you mean, and I completely agree, Steve; graphs without axes titles are nearly useless. Who knows what they show?

[strata]

I have modified my speakers by replace the damping material to audio wool and dressed the inner chamber walls with bitumen. It did a huge difference in terms of better and firmer sound through out the whole register. Here is the link to the wool.

http://shop.monacor.se/servlet/us_pyra?wts.PAGE=h_ix3.htm&$GUEST=GST&wts.ACTION=loginguest&p=H

[fetteler]

Johan,
I wonder if, as an experiment, it would be instructive to block up the cabinet vents entirely and see what effect this has. In the back of my mind I am wondering if there's a cancellation effect at low frequencies This would show it up for sure.

Cheers,
Steve.