Speaker kit experiments - an archive of the Jäger Speaker development

[debk]

What a great idea!  That I will have to do when they are out

Debra

[Doc B.]

A small update  - I have quotes for different materials, save for one that I had requested but was missed. The choices are plain MDF, cherry veneered MDF, Baltic birch and Bamboo ply (similar to Blumestein speakers).

The Plyboo looks very good on paper and of course we know that Clark does great things with it. But in as big a cabinet as we are talking about the cost is "yuge". And my understanding is that sanding before finishing is a long and tedious process. Clark definitely earns his very reasonable prices!

I suspect plain MDF is a deal killer for most folks. A material that is so unfinished seems going in the wrong direction considering that the cabinets assemble in about 15 minutes each. Slapping on some flat black paint is a simple finish, but not really worthy of the sound quality IMO.

That leaves us with Baltic birch and cherry veneer MDF. I don't have the birch quote yet. If it seems reasonable I may have some made up to try out. If it seems beyond the price range I'd like to stay within, I know that the veneered MDF prototype is performing very well and should be easy to finish with something as simple as a light sanding and wiping on a few coats of oil. That should work nicely with the look of the amp bases if finished the same way. And of course one could stain it and do other types of finish as well.

[debk]

MDF vs BB that's a controversial subject.

Seems like BB wins out in most of the literature I have read.

One of the disadvantages of MDF is that the dust from cutting and sanding can be a health hazard

Debra

[Doc B.]

Luckily since the panels will be premade MDF dust is not really an issue for the end user. Any sanding would be done only on the relatively benign cherry veneer before applying a finish.
The main theoretical advantage of birch ply is that it is somewhat more stiff than MDF. Plyboo is even more stiff. But as I say we need to keep the cost in mind. The MDF seems to be working quite well, with the cabinet feeling pretty vibration free thanks to the internal bracing.

[debk]

i was actually thinking more about you guys if you where to do all the cutting.

Debra

[Doc B.]

John Rutter of Harmonic Design Works is facilitating the manufacture of the panels for us. John has been providing wood bases for us for many, many years and I have great faith in his abilities to get the job done right. The cabinet panels are being done at a local (made In America, yay!) cabinet manufacturer John works with who has CNC capabilities. CNC is the most cost effective way to get the repeatable accuracy that we need for cabinets that go together with the cam locking system. The safety regs for woodworking manufacturers are pretty strict these days and they typically have very effective ($$$) dust filtration equipment. JR can probably tell you stories about how much he has had to invest in that stuff.

[debk]

thanks for the info.
I really am looking forward to this

Debra

[caffeinator]

I like the look of cherry and am fine with MDF as long as it's wrapped (or at least externally covered) in a veneer.  Either BB or MDF/veneer sound great to me.  The idea of the cam-lock assembly appeals greatly.

FWIW, I have my S8's with the flat-pak veneered cabs still going strong.  I know they're veneered; can't recall what's underneath.  Whatever it was, it's been wonderfully durable and low (really no) maintenance and still looking lovely after all these (like at least 15) years and at least four inter-house and many intra-house moves.  The assembly of the flat paks was straightforward and fun; just enough effort to feel like I more or less made them but without the 'teachable moments' of my other speaker cabinet projects.

Really looking forward to these and saving my pennies already.

[Doc B.]

S8 cabs are veneered MDF. They were finished and these will not be, so that's one difference. Another is that I think these drivers sound quite a bit more refined, particularly in terms of imaging, than the S8. The assembly of the cabinet will be similar in terms of effort. The new crossover will be a bit more work to build than the S8 one. Have not figured out how that will be packaged yet. I'm leaning towards an external box, as we plan to offer an active tube crossover in the future to replace it. The wiring of the new speaker will be much less work than the S8. Wiring those 8 woofers was a royal PITA.

[caffeinator]

Hi Doc,

Sounds great to me - I'd gladly trade all that internal speaker wiring, especially with that coated wire, for more external build (the crossover) and some cabinet finishing.  An external crossover with the possibility of a future active tube version is also an intriguing and attractive option.  A perhaps dumb question - could the crossover (either version) be implemented upstream of the amps to facilitate a bi-amp or multi-amp setup?

[Doc B.]

Yes, that is part of the plan. I will be experimenting with biamping the passive crossover soon. A Kaiju biamping each channel should sound great. Or a couple of Stereomours, Seductors, etc. And of course one could instead connect the passive crossover in a more traditional manner for a single amp and strap a Kaiju or a Seductor too. There will be lots of room for experimentation.

[Doc B.]

Bit by bit - yesterday we verified that the bass ports hit their design frequency of 37Hz nicely. It's not clear in the photos I have shown so far, but each woofer is in its own ported chamber. There is a solid planar brace at the midpoint of the cabinet's height (i.e., right between the woofers) that effectively splits the one cabinet into two bass cabinets.

[Jay]

I should have held off on those Great Plains Audio 604's.
Jay

[tdogzthmn]

I should have held off on those Great Plains Audio 604's.
Jay

I'd love a pair of GPA 604's!

[Doc B.]

A quick update -

We have some quotes from the cabinet manufacturer and we are evaluating what the best price/performance material will be. In the meantime the manufacturer is making up another prototype cabinet for us to check on a few design changes regarding the way the cabinets assemble. Dimensions have not changed from the first prototype. When this second prototype arrives we will be able to evaluate the performance of a stereo pair. They hope to make the parts this week. Fingers crossed...