Fonken 167 enclosures build- notes

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Hi-
I moved the new Fonken167s up to the living room yesterday, and thought I'd post a few thoughts and pictures. These are floorstanders with Easttech bass drivers in a 14L box in the base, for some added help at the bottom end. I haven't hooked up the bi-amp setup (just casing the amps) yet, so the bass drivers are just decorative at this point. These boxes are very fine-sounding, and definitely a 'step up' for the 167s in my (modest) system.

First, a big 'Thanks' to Dave at Planet10 for the plans, advice and couldn't-be-beat deal on the bass drivers.
Contact Dave for plans and info, as well as 167 enhanced/modded drivers and phase plugs.

John
 

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Construction-
As per the plans, the boxes are 18mm Baltic birch plywood. Heavy stuff though not as bad as mdf , so you will be glad to get the 5x5 sheets ripped into smaller panels if you have limited working space. Wrapped in cherry wood-backed veneer.

I wouldn't rate the boxes themselves as difficult to build, though there are quite a few parts and you need to think through the assembly sequence. However, they are difficult to get a very clean finished result, as the vent openings and trimming the veneer give lots of opportunity for 'cosmetic' mistakes. (I made plenty). If you can be happy with a flat or textured paint finish you can save yourself a lot of 'fussy' work, and the sound will be just the same.

Cutting the bevels on the front corners was not very difficult with a 10" table saw with a good outfeed (and infeed) table. It will be worth your while to take an hour or two to set up temporary feed tables to keep these cuts under control and safe. The boxes are heavy and need good support.
 

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Veneering-
I hadn't worked with thin veneers for many years- I generally use sawn veneer on projects where I can't work in solid wood. It's obviously an area where a bunch of mistakes will be made before you get the 'knack' of working with the material.

This Australian publication is a great resource for techniques to use with veneer- both 'real' (thin/fragile) and sheet veneers. Modern sheet veneer like I used (4x8 sheet, wood-backed) is very tough and easy-to-handle compared to standard veneer, and eliminates the problems of joining and taping to cover large panels. However, the veneer layer is very thin - it seemed thinner than standard veneer- so you should take care not to sand through- hand sanding (if at all) is recommended.

I used the yellow glue and iron method on the veneer- I tried using my vacuum bag system, but had problems with uneven bonding- probably the glue was not thinned enough. For vacuum bagging Titebond makes a special veneer glue which might help (I didn't try it). A new $10 iron with a stainless base and 'shot of steam' feature was a help as well.

I found that the edges tended to have bond problems, so I ran a thin bead of CA adhesive along the overlapping veneer joint before trimming with a block plane and hand sanding.
Note- the wood backing on the veneer is a luan-type wood, which is softer than the face veneer, so the surface is easily dented- you will need to take care to pad your workbench. Just a 'touch' on the bench edge can leave a visible mark, and steaming out dents is problematical with the ironed-on veneer system.

The project took a few hours a day for about a week- so no instant gratification. Making the jig for the recess for the 167s took some time, and the home-built circle jig needed a few more holes drilled to match the drivers.

I'm happy with the result- these are very good-sounding speakers.

Cheers
John
 

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AuroraB said:
Very nice build... and very intersting!

Are these plans published? _ in that case I missed them!
What is this - a 167 Fonken with sort of integrated sub - or ?

Thanks for the kind words.

For plans and info, contact Dave at Planet10 .

The 'normal' Fonken167 floorstanding boxes have a void space at the bottom- with a bit of modification they can handle a sub/bass driver.
As I mentioned, I haven't hooked up the bass drivers yet- the 167s on their own are doing a very respectable job delivering the music. I do like bass, so perhaps tend to demand more than necessary in that area.

Cheers
John
 
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Good work John.

AuroraB said:
Are these plans published? _ in that case I missed them!
What is this - a 167 Fonken with sort of integrated sub - or ?

Plans are not officially published. I have been distributing the early plans on request. Since all of the builds have been executed with a few aesthetic changes i do want to get those into the plans before giving them out anymore (won't take me long).

Here is a thread which covers the 2nd pair (that we know of) made.http://www.audio-talk.co.uk/phpBB2/viewtopic.php?t=1397

Chris has 3 more pair at the finishing stage, 1 pairr of which are for our own use, so we'll have a set for the upcoming diyFEST.

It is good to hear that John likes these better than the ML-TLs the 167 were in because for the effort involved they need to be :) It is also nice to see the twist of repurposing the void at the base of the cabinet for bass helper duties. As configured Jiohn has a 1/2 ft^3, one could move the 167 down a notch or 2 (should be placed with the midpoint between 2 slot vents) to gain more volume, Bass driver could be placed on the side to accomodate a (but) larger driver. It would also leave room above the 167 to add a tweeter to end up with a bi-amped, mostly full-range hi-efficiency 3-way.

dave
 
Some questions:

What had you heard the 167's in previously?
How would you characterize the sonic difference between the two designs?
How is the bass of the Fonkens alone?
Where do you intend to cross to the woofers?
How low do you expect the woofers to get?
What are the (approximate) exterior dimensions of the Fonken167 without customization?

I've got plenty to keep me busy ATM, but my 167's keep whispering in my ear about the Fonken enclosure...

Thanks!
 
Adam, I can answer a couple of these questions:

Fonken 167 approx internal volume 27 liters (net of lateral bracing). Dave is currently revising the drawings to reflect some aesthetic revisions per the last batch (4 pairs)

AFAIK, John's only previous speaker with 167 was another DIYer's build of Bob Brines' MLTL design (in Baltic Birch)

My own experience with the 167 includes a variation on the stock Fostex BR enclosure (i.e. modified dimensions to Golden Ratio), Scott Lindgren's/Planet10 Demitri (aka the Audio Magus White Lotus with Hemp Acoustic FR6.5), and L&R mains and center channel for a custom 5.1 HT system (with dual CSS woofers per side)

Based entirely on subjective (visceral) listening evaluation, I found both the Demitri and MLTL to extend deeper at the bottom, but at the cost of control and articulation.

Perhaps it`s due to over 2 years of listening to various incarnations of the original Fonken (Prime) design with both FE127E and the steroid version with F120A, but I find the imaging, soundstage dimensionality, and smoothly controlled bass roll-off of this particular design format to be its major advantage over all others I`ve heard to date (including the Floorstander and milli siblings) with the same drivers.

A close second would be the Brynn (which I`be built) or presumably the Half Chilli (not yet)

Caveat: in most cases the drivers involved were fully treated with the Planet10 enhanced EnABL process, and in the case of FE167E, with phase plugs. It`s probably not overstating the matter to say that these treatments far exceed mitigation of some of the characteristics that cause many listeners discomfort with the Fostex Sound - particularly in the case of the FE127E, the transformation is quite remarkable.
 
AdamThorne said:
Some questions:

What had you heard the 167's in previously?
How would you characterize the sonic difference between the two designs?
How is the bass of the Fonkens alone?
Where do you intend to cross to the woofers?
How low do you expect the woofers to get?
What are the (approximate) exterior dimensions of the Fonken167 without customization?
Adam-
Thanks for your interest and questions.
Chris has hit most of the answers to your questions.
I am not at all into describing sounds in words, so you will have to take that into account....
I am big on bass,and of course it's the bass that's affected primarily by the enclosure- the mid/highs are coming right off the drivers.
Previous enclosures were Brines 1600s. V. good sounding boxes. Part of the problem was that cosmetically they needed a bit of work, and I decided that it would be more fun to just build something different- thus the replacement. They did have bass that went lower than the Fonkens- more 'whump' , but it was not as 'crisp/tight' . With a lot of speakers and poor recordings, I find that I can hear 'lots of bass' but that it is hard to tell what note is being played- ie not enough fundamental and too much lower overtone in some cases. With a recording that gives the bass its due respect ;) , the Fonkens do a fine job. I'd think that many folks would be happy with them without any more bass reinforcement. (Patricia Barber:Companion is one of my 'test discs'- sounds great).

I'm not into the home theater thing- just music- so I'm sure the woofers will fill in the bottom of the music just fine. If I want the 'blow-em-up' stuff I guess I'll install 'seat-shakers'....

Re: crossing point- You probably know more than I do about this (which would be easy). Right now I'm looking at somewhere in the 300Hz range- with line-level XO the components are cheap and easy to find in the parts box, so changes just take a few minutes. I may just run the 167s 'straight through' without any LF roll-off and just use a low-pass on the woofers. With lower-order , gradual slope XOs it seems a bit easier to make things smoother so perhaps a bit more latitude for errors. I'm putting trimmers in the LF/HF feeds so that I can keep the levels balanced- I just want the woofers to help, not really detract from the 167s.

re: Fonken 167 dimensions- Plans are still a bit in the 'beta' stage as I understand it, so you should contact Dave(Planet10) for info. My copy of the plans show 88x28x24 cm (HxWxD) exterior dimensions for the 'standard' box.

re: 167 drivers- My 167s have P10 phase plugs and Puzzlecoat/ModgePodge 'pre'-treatment.


Cheers
John
 
To expand further a bit on John's above post - a great demo track for Patricia Barber fans would be virtually anything from Modern Cool, but particularly "Constantinople", "Post Modern Blues", and "For Company" ; and for the lyrics alone "If This Isn't Jazz" from (Companion)

Another of my favorite tracks for vocals are Eva Cassidy, "Fields of Gold", and "Tall trees in Georgia", from Live at Blues Alley

if the latter is only a chick and guitar, I can live with it.
 
Just a quick update:
While I'm working on the bi-amps and making decisions there (integrated input switching/volume or just power amps?), I set up a temporary bi-amp rig:
CDP/DAC --->Volume pot---->Passive XO---> Amps---> Speakers
feeding the Hipass to the 167s and the loPass to the Easttechs. I didn't like the result as most of the 'good, tight' bass wasn't getting to the 167s. So I changed the setup so that the 167s are getting unfiltered feed after the 'master volume' and the Easttechs are getting the bass feed after the volume pot and LoPass (around 300Hz).
Fullrange amp is MauroPenasa myRef, Bass amp is Dokorder800X.

Result- the Fonkens are still great on the jazz/folk/vocal stuff, but now can better handle rock. Also bass lines in general have more power.

BTW, as Dave mentioned in another thread- there will be no need for a trimmer on the bass feed- they need plenty of input to keep up with the 167s.

Cheers
John
 
300 hz is higher than I would have guessed, since I figure the 167s as competent an octave or 2 below that. Especially since your XO is line level, so components are relatively cheap. Do you intend to try out lower points?

My 167 Metrinomes switch over to my sub at 90 hz or so. Of course, that's a traditional separate sub w/ plate amp, so it has to cross lower.
 
AdamThorne said:
300 hz is higher than I would have guessed, since I figure the 167s as competent an octave or 2 below that. Especially since your XO is line level, so components are relatively cheap. Do you intend to try out lower points?

Adam-
The 167s are doing 'full duty' and the gradual slope of the low-pass filter for the woofers means that in practice they are just helping out where they are needed. Having volume controls on both the bass and full-range amps (as of now) as well as the line-level 'master volume' means that there are lots of 'balance control' possibilities.
One benefit of the present setup is that the drop in level with the extra pot means that all the volume controls are now working in the mid & upper ranges of adjustment where tracking errors have less effect.
It seems to be working well, but of course 'early days yet'. Lots of scope for twiddling and tweaking.
As you mention, line level filters use small and cheap components, so changing things is quite easy. The new bi-amp case is large with plenty of room for a couple of solder terminal strips for the filter components.
(BTW, this is all still my 'second-line' system, though it gets most of the playing time these days. The MusicMachine and the AN10s are still a step above, IMO, especially for small combo music.)
Cheers
John
 
>>> Another of my favorite tracks for vocals are Eva Cassidy, "Fields of Gold", and "Tall trees in Georgia", from Live at Blues Alley

I had this cd and lost it! Eva's amazing.
Godzilla


One of my absolute favorites - tracks 7 -9 never cease to choke me up

I often muse what Sting would think of her rendition of "Fields"

She already knew she was sick when she sang "People Get Ready"
 
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