MDF? - Onken Cabinet for Altec Duplex 604E

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Hey all ..

two questions....

Could someone with knowledge about this certain wood horn:

*is the curve correct on the Yuichi A-290 Horn on my drawing ( see attached drawing ) ?

**what driver(s) should I consider for the A-290 Horn?

- - - - - - - - will the EV DH1A driver work until I get ahold of a better one?
 

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simple Google search on the 755a - glad to see KimPak - assume its like the great old "Kimsul" (?) fwiw I used N1500a scheme with my 604e in a Karlson - very nice on things such as Hans Hotter's Winterreise, Gary Karr's Koussevitzsky album. Stan Ricker ran 604 with just a small highpass cap.
 
Kimsul is another Kimberly Clark product simliar to Kimpak but it is impregnated with some kind of oil or resin. Kimsul was actually marketed as acoustic and thermal insulation whereas Kimpak is packing material.

Works great for 755A cabs!

Hard to do a google search on these products because you will come up with 1000 Korean references...Kim Pak, MD. Kim Sul Choi, etc!

I suppose the key to happiness with any speaker is to have only problems you don't care about or the ability and inclination to listen through them. Personally, I never got there with 604s but maybe someday I'll try again.
 
I´m quite sure the drawing is correct. I see on this page : Wood Horn
- that the pictures of the horn has the same type curve as the drawing that is attached in my previous post.

Since this thread spans a lot in topics addressed -

I have something I wanted to ask about the 604E duplex

I think you GM talked about the last time he heard a 604E playing it was EQ-ed differently than with the original N-1500A crossover. - was this done digitally?

I was wondering if anyone has tried DPS and SMAART ( for example : miniDPS and a REW like explained on this site: Stereo 2 Way Xover )

Will the 604E duplex preform better this way?
I have read that the 604E duplex is notoriously known for its ragged frequency response.

What difference will a budget DPS system make on my 604?
 

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I'd say that miniDPS and REW would definitely help you out a lot. Aside from possibly being the shortest path to ALTEC Nirvana, it would be a very useful learning tool.

Moving beyond off-the-shelf passive crossovers would require access to something like REW anyway (if you want to know what the filer is actually doing)...plus a heck of a lot of work and relevant knowledge.

However, it might be worth having something like N1500s around a a point of reference. It will probably end up on a shelf in the garage.

The miniDSP-->biamp setup will also allow you to tailor the amps to the individual drivers. When I had my Onkens bi-amped, for a time I used strong PP 6L6 AB2 Altec 1420s on the woofs and a pipsqueak single ended amp on the highs. The original French Onken cats liked small Class A transistor amps. I heard that the Japanese liked big Onken systems with 200W transistor amps.

Most people don't have an amp around small enough to underdrive the Onkens but some of us do. I have run the whole system on 3.5W SE 5998 amps and even a Fi 2A3 SE but the woofers started waking up with 8W or more.

Those wood horns woukl probably kill on a high-quality small 2020 T-Amp or similar. Doesn't take much power to rock the joint with those but it's gotta be smooth or you will die.
 
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Sorry to be late to this thread. Not been on the interwebs much lately. My reply wont be all up to date. :)

Never heard an MDF Onken. Don't think i'd build one. But if thats what the budget allows, OK. Would OSB be any better? In California you can get the thick stuff.

I don't know the crossover Mr Hiraga used, he would not say as it was meant as a commercial venture. Wish I knew as JH is a master of the passive crossover.

If you start with your 604 and a Markwart crossover you will have something ver nice. Later you can add a big midrange horn and still use the 604 horn as a tweeter. I've done that and liked it.

FWIW I have used the 605 & 605 on OB and the 604 in a big 12 cu ft BR box. All were different, all worked well. All needed different crossovers.
 
*I guess the ONKEN cabinet will be built , I`m not sure if they will be built in MDF or birch plywood. I can't make up my mind about that.

I tried working with MDF only once. I didn't like it all. No complaints about sonics but working with it is horrible. I don't have a proper shop and due to the toxic dust have to work on the driveway - but even then the dust was awful. Even with a face mask it found a way into my face. Just awful stuff - I will avoid it like the plague. It's also darn heavy, noticeably more awkward to work with than BB ply. And it's harder on tools, high speed router bits and the like will experience more wear and tear.

So I vote for BB ply, even if it costs more. And it's possible to get a nice finish on the ply without veneering it as I did here:

The Big'un - A Large Mono Loudspeaker

If I had a proper shop to deal with MDF dust it would be easier, but my time if valuable, and in short supply, so why bother making something where you are second guessing it.
 
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Yeah, cool offbeat choice. I remember finding a small vintage enclosure like that with an 8" in it at a hamfest in the 80s

What's the story? Does the port fire into a space between the front panel and the baffle board in such a way that the port hole is also the speaker hole?

They sure tried a lot of freaky stuff back in the 50s when hi-fi was young.

The Karlson enclosure in your avatar reminds me of a story told by Wayne Green, who was the marketing guy for Karlson and later editor of 73 Ham Radio Magazine.

Karlson apparently had a design for widebanding a microwave slot antenna and he decided to make a speaker based on it, The design was published and the speaker cabinet scheme caught on. Eventually they had like five companies making boxes to meet the demand. Wayne admitted, however, that all this time they weren't exactly sure how the speaker worked beyond the notion that a slot of varying width should spread the resonance of sound waves like it did for RF.

A similar concept later showed up in the Altec tangerine phase plug with its thin triangular slots.

"Modern" speaker builders would never come up with either of those designs. Too worried about diffraction, BSC, and whatnot.
 
Well, the 1952 Jensen Transflex tapped TL is the first BP6 I'm aware of, though it wasn't touted as such and nowadays is viewed as a tapped TL [TTL]: Jensen Technical Bulletin No. 4

B0s3 became the #1 consumer brand with their various 'subs', some of which were coupled cavity [vented] 6th order, but don't recall actual model #s these days.

Around here, the various tapped TL, TQWT, 'horn' 'subs' that dominate the Subwoofer forum are acoustically series tuned 6th order [BP6] alignments in that instead of a series of coupled [vented] cavities combined to load both sides of the driver to a vent exit [terminus], a tapped [straight or tapered] pipe is all these cavities, vents morphed into one long pipe folded back on itself with the driver at 'x' amount of offset at the closed end and at 'y' offset from the terminus, which in compact designs is usually the same offset, whereas the low tuned ones have a 1/4 WL offset at 'y' after the DSL DTS series of THs.

A [no longer available] DTS10 subwoofer kit build-up, measurements to better visualize it and its performance potential/net bulk: Danley DTS-10 "Super Spud" DIY kit - AVS Forum | Home Theater Discussions And Reviews

GM
 
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