Can CHR-70 work in a tall MilliSize (DeciSize?) Onken?

[TheSeekerr]

Hi,

A question that's probably best put to Planet10: can CHR-70 work in an Onken-ish bass reflex box? A quick spot of modelling suggests that something on the order of 10-12 litres tuned to around 50hz should work quite well.

I have an application where I can go practically as wide as I like (thinking around 16ish cm - am I right in thinking that the response of the CHR-70 negates the need for baffle step around this width?) and up to 40cm tall, but no more than 21cm deep.

Budget for this build (it'd be a gift) doesn't stretch to a sub, so it needs to be ported to achieve reasonable extension. Which brings us back to all things Onken-ish - a millisize is definately too small, while a primesize is too deep. Is there a practical way to modify the Onken shape into what I want it to be, or is it time to hit the drawing board?

[planet10]

The CHR would require a box larger then milliSize for sure. When i went to put it into said size i ended up with sealed. The CHR is broadly similar to A7 in terms of boxes, so recent development of the deciSize dMar-Ken7 has me thinking it is time to look at the CHR in this size box.

Taxes and some Metronome drawings are ahead in the queue thou.

dave

[TheSeekerr]

Hi Planet10,

Any chance of getting the Decisize dimensions? Just rough exterior will do.

[planet10]

I'll have a look at the curves to-night and see if the guess is right.

dave

[planet10]

10 litre tuned to 51 Hz, needs the high aspect ratio long ports to bring the Q down. should approach bass performance of miniTower. F10 in the low 30s.

dave

[TheSeekerr]

Awesome, any ETA on plans for decisize enclosures? I seem to recall that there aren't any published for the A7 yet either.

(also, will it fit in my 21cm depth restriction? My rough guesses were suggesting it would be hard to fit the ports in)

[planet10]

The A7 dMar-Ken7 is actually a bit smaller at 9 litre.

I went back and klooked at the CHR. 9 litre 51 Hz is actually a bit better.

The A7 box is 220.4mm deep, but tuned a tiny bit higher.

So in the CHR box the port spacers will need to be a tiny bit shorter.

Because of a licencing deal with a Danish company, plans for these will cost a token amount (and end up being very extensive), but i do need some beta builds. if interested email me I could get basic drawings out fairly quickly.

dave

[TheSeekerr]

220.4mm is acceptable - the absolute maximum was 225, this suits me just fine

I'll email you shortly.

[planet10]

Here is the visualization of the deciSize Alpair7 box. The CHR bezel is smaller, and as mentioned port spacers will be a bit shorter.



dave

[Henkjan]

I have the CHR70 in 4 liters sealed (with HP capacitor)...... small enough?