Mark Audio CHR-70 Application Thread

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Triffid... a simple little TV/FM/CD speaker

Quick easy speaker for a small room driven by 20W using DVD/FM/CD as sources.

Vented speaker, Vb=6 litres, Fb=59Hz, F3=49Hz, option of BSC / no BSC, long hair wool damping in the lower 200mm of tube, selective damping on inside walls. Can go lower but I've picked a compromise between low extension and power handling and the BSC is not required in it's current application.

Not usually a fullrange user but rate this driver above FR125S (sealed, vented), FE127E (vented, TL), W3-871SC (vented) in that order. Gets a thumbs up as a fullrange driver as unlike a lot of the others it does cover a broad range very well just like the FR125S but with a bit more life and detail. The detail can go missing in action when things get congested but that's to be expected at this price point and driver type.

The SPL is not a problem in my case as most amps have excessive gain anyway. The low impedance could be an issue for some amps (some tubes?) and also ChipAmps that are running high rail voltages.
 

Attachments

  • chr70.jpg
    chr70.jpg
    62.6 KB · Views: 5,685
italynstylion said:


^I never got a response to this. If my terrible math is correct that would mean all 3 sides should be ~1.155inches?


Well Scott can correct me on this, but I think the exact geometry of this part is one of the lesser critical areas of the design. IIRC, on the Aiko with a similar wedge, I used a right / isosceles triangle (45/90/45) as I frequently use this shape for inside corner blocks as well, and had a few dozen feet of material pre-cut.

So with a height of 1" (25.4mm), the sides would be 1.41" (36mm)
 
I started clamping a few things today and got carried away. I ended up finishing the assembly for the BVR's. They are still bare wood but I'm going to test them out and listen to them a bit before I finish them with paint.

Honestly, I would have heard them tonight if it weren't for one thing. I thought I had a bunch of really small screws to mount the drivers. Actually, I do have them....but they aren't small enough! I didn't realize just how small the mounting holes are. It's ok though. I'll hear them tomorrow morning after I go to Lowes and get some screws.
 
Friend of mine might be commissioning me to build him some new speakers for his home theater system. I'd like to try something nifty with the CHR70s. He wants something relatively badass to go with their 58" plasma and all that, so I was thinking pairs multple chr70s for left, right, and center, and a single chr70 for each of the rears. Floor standing BR (or maybe something fancier?) for the left and right, sealed center and rears. They already have a decent powered sub with adjustable crossover.

now, with the whole "doubling up full-rangers" being a problem with the phase cancelling thing, I was thinking of other ways to incorporate these drivers into multi-way speakers. First I was thinking maybe two CHR70s as mid-bass drivers, with a single Alpair5 in the middle running the highs.

Getting into the Alpair stuff might be a little overkill in this case, and I'm thinking "if the CHR70 is enough quality but just not enough quantity.. why not just add more of em?" So what about a 3-way CHR70 floor stander, with the top and bottom drivers running mid-bass, and the center one running highs.

Am I totally off my rocker?

Would certainly look slick, anyway :p

I was thinking wire the midbass units together in parallel, and wire them in series with the treble unit, then balance them out in the crossover, working out to a overall 6-8ohm unit, which seems tasty
 

Attachments

  • front.png
    front.png
    30.6 KB · Views: 1,834
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.