Should I Build: Onken Box For Altec 604E?s ?

[Tralalalala]

Hi all,

I?m considering building a pair of Onken boxes for my Altec 604e?s?

Today I got a pair of 612C DIY cabs.


Anyone out there got any experience with Onken boxes with Altec gear, - especially the Duplex series?

I?m eager to hear what you got to share / tell me about the design...! - sound, size and how to build... etc..

I will use a low watt class A transistor based amplifier for this Onken setup - like the Hiraga "le Monstre" - 8 watt class A amplifier .



I?m hoping someone out there got something to share !

Best,
Tralalalala

[Cal Weldon]

Onken style boxes have a good reputation with Altec appreciators.

[Tralalalala]

Hi !

Maybe I should be more specific about my questions:

I?ve looked into the ONKEN design:

The building of the design is described thoroughly in this article ;

Untitled Document

There is mentioned use of hot glue in this article - used by carpenters - to build this ONKEN design - is this rabbit skin glue ( organic )? - or is it another type of hot glue?

[Tralalalala]

OK.

This is my third replay to my own thread ;-) - not too fun... BUT:

I will not give up that easily !


So I?ve drawn up the ONKEN box digitally.

You`ll find two attachments in this post!


1. I?ve now made contact with a US company that produces hide glue.
Will keep you updated!

Where I live there is possibilities to get a hold of 24mm baltic birch plywood.


Three questions:

1. Bevel was a long subject in my thread about building my 612C cabs.
I?ve seen pictures on net that there is no bevel around the speaker opening on ONKEN cabinets-
Should I or should I not build the ONKEN design with a 45 degree bevel?

2. So I?ve built a 621C cabinet with 45degrees joints - this ONKEN design is not built like this - probably not the original 612C cabs either...
Why is it so - pros and cons of straight and 45degree joints on a speaker cabinet? ( I can build stuff - but I?m not an expert on speaker design at all.... )

3. If straight joints can I use lamello biscuits instead of screws around the box and on fixed parts?

[GM]

Greets!

I?ve built one pair of the Onken 360 loaded with 416-8Cs for a neighbor way back when, compared it with my tower variant with single large vent [aka [ML]TL or [ML] TQWT nowadays] and we both preferred mine as we felt it was the more accurate reproducer, i.e. a ?tighter?/?dry? presentation. It also showed a flatter response using a 1/3 octave RTA.

I would on any rear mounted driver with an XO point > ~4316?_sec/cutout diameter to ensure its cavity resonance don?t audibly comb filter with the driver?s and/or HF response.

Since it?s an Onken with relatively huge amounts of [lower] mids harmonic though, it?s a moot point, so only do it for cosmetics if so inclined.

Only some consumer products employ mitered joints, all others are either dowel, cleated butt joints. Screws can be used for cleats, otherwise are a no-no as it weakens the joint. For temporary pinning purposes, use wire brads, staples or finishing nails.

Since you?re using an amp probably with a similar output impedance and assuming your 604Es have the older low Qt motors, then the cab size, tuning should be fine for the 360.

Don?t read French, so no clue about any particulars and had to convert all metric to decimals for us to build his cabs, using cleats, finishing nails and whatever wood glue was sold at Home Depot [probably Elmer?s Construction back then] to bond it all together. FWIW, once PL400 came along in caulk tubes, I only use it for any serious construction.

Spending $$ on some old tech glue seems a complete waste, but whatever ?floats your boat? as long as it?s not elastic.

GM

[Tralalalala]

Hello GM ,

Thank you so much for your replay!

The amp will work fine with the original specs of the 604E?s - for your information:
the speakers are set to 16 ohm imperdance operation; both speakers have new cones and new diaphragms from GPA.

I have built a copy of the N1500-A crossover with components described on Jeff Markwarts site.


After your replay I understand that the use of staples with straight joints is probably the best way to go.
I will probably not get a hold of the hot glue - it is way too comprehensive start building stuff with hot glue - I got too carried away there....

And after your input ; understand the reason why there is no bevel on the Onken cabinet .

Thanks.

[Altec Best]

Do NOT (Rabbet or Dado) the braces into the panels as this will weaken the panels.This will cause them to resonate IMHO..

[Tralalalala]

Thanks!

Understand.

Good - Will then use butt joints with headless staples for these braces. and glue of course...

[Tralalalala]

Hi,

Attaching full cutout plan for the build of the 360L Onken box.

uhm.. parts that are not included in this drawing ; the frames that will hold the front baffle in place. I will probably use 2" 3" pine for this frame.

One question:

I did draw this cabinet with a 27mm plywood. ( thats somewhere in between 5/4" and 4/4" )

Is it a big difference building the cabinets out of 27mm and 24mm plywood in this design?
Difference is in inches : 3mm = 0.12 inches.

[Audio_by_Goodwill]

I did draw this cabinet with a 27mm plywood. ( thats somewhere in between 5/4" and 4/4" )

Is that something that you can source locally? Plywood greater than 3/4" is not common in the US.

I could see going with a thicker material front and back, but the sides should be pretty strong considering the two panels are so close together, connected with the braces.