Mark Audio CHR-70 Application Thread

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HareBrained said:
Even listening to a KEXP podcast of Steve Earle, which only 192kbps, sounded fantastic.

In my experience, the soundcard (and driver) has an incredibly large amount to do with lossy format sound quality.

My Yamaha DS-XG50 makes .mp3 sound bad with the Windows drivers, but oh soooo sweeeet with the Linux ALSA drivers :)

:2c:
 
well I know this is probably heresy but...

I just ordered two pairs of these and plan on using them in a cabinet with
a separate woofer. I don't know which woofer but I have had great experience with
the JBL LE14a. I don't know, maybe one of Dayton's aluminum cone RS series subs.

Anyway, I would like to use these open baffle for the top end. I am wondering if I am going to need two drivers if I am not asking it to do anything below 150hz? If I am going to need two drivers can I mount them at right angles like the previously mentioned designs, but on an open baffle? Would this create any problems?

Optionally I could use them in a bipole configuration?
 
In my experience, the soundcard (and driver) has an incredibly large amount to do with lossy format sound quality.

My Yamaha DS-XG50 makes .mp3 sound bad with the Windows drivers, but oh soooo sweeeet with the Linux ALSA drivers

just wondering if this was specific (more evident) to the chr70 or is it for all your speakers? I'm pretty curious about the difference between different sound cards. From what I've experienced most inbuilt ac97 and intel hd audio cards are pretty similar with alsa and windows drivers
 
gychang said:



waiting for a "guest room" (not BIB size but smaller foot print) floor standing, stylish model with adequate bass. Can't wait.

gychang


"adequate" is a bit of a nebulous target to aim for, but if the guest room you're talking about is less than 300 sq ft, and SPL levels needn't be excessive, I'd imagine there are any number of enclosures that might fit the design brief.

Indeed, I'm a couple of days away from buttoning up a couple of variants on a new compact floorstanding enclosures for the CHR70 (an other similar drivers) from the DaveD/Planet10 idea engine. We try to actually build an listen to at least one design from each new genus before getting to excited about publishing drawings, so the one hint for now is - bipole.

and, oh yes - "many things old are new again" (along with, when we're lucky, perhaps a new perspective of, or lexicon for describing how they work)
 
frugal-phile™
Joined 2001
Paid Member
And here is a teaser for one that probably isn't diminuative enuff for Mr Chang's need :D

Muhahaaha

maeshow-c-3D.gif


Meant to load into a wall or corner. Suitable for CHR-70, FE126e, and a 3rd (not yet released) driver. This is actually a spin-out from working on Frugel-Horn Mk II

dave
 
planet10 said:
And here is a teaser for one that probably isn't diminuative enuff for Mr Chang's need :D

Muhahaaha

An externally hosted image should be here but it was not working when we last tested it.


Meant to load into a wall or corner. Suitable for CHR-70, FE126e, and a 3rd (not yet released) driver. This is actually a spin-out from working on Frugel-Horn Mk II

dave

Oh, my... this is great.

any chance on the dimensions?

gychang
 
2 HareBrained: Please Help

HareBrained said:
....
The driver opening is visible through the far chamber. Half-inch material was used throughout. Because of some errors on my part, I had to use MDF for the port walls. All ports have the same effective length (slot port effective length is longer than actual length by half the height due to end being next to wall.) The height of the ports is 3/4". I used a couple of scraps of wood to set the spacing. The center port does wrap on both ends, again minimizing the walls. The driver chamber is twice the volume of the other. Besides the obvious stuffing, I glued some foam behind the driver, and I'm thinking of adding a little acousta-stuff in the driver chamber.
....
- John [/B]

Hi John,
I had no experience in speakers design; just trying to reproduce your design. Could you please review my dimensions?
  • I’m not sure that ports are right size.
  • Speaker is centered by tom chamber, so it slightly closer to one of the sides. Can I place speaker (vertically) in the middle of front baffle?
  • What the right place of the center port? Numbers on picture (9 5/64 and 10 27/64) are wrong. What are right ones?

If you want I can send you my Google sketch up file.
Thank you,
Vlad
 
frugal-phile™
Joined 2001
Paid Member
_henry_ said:
it looks good, is it possible to do with Alpair 10FR?

Maeshow is large. If even possible A10 variation would be huge. A ball park would be multiply the ratio of Vas by the size of Maeshow.

Martin has designed an A10 horn, that should be fine once the excess bass has been figured out.

Details of how full Maeshow plans (with a few others we have had in hiding) will be made available will be announced after Scott & i figure out the timimg & the details.

It is 5' tall.

dave
 
Re: 2 HareBrained: Please Help

Voldemar1 said:


Hi John,
I had no experience in speakers design; just trying to reproduce your design. Could you please review my dimensions?
  • I’m not sure that ports are right size.
  • Speaker is centered by tom chamber, so it slightly closer to one of the sides. Can I place speaker (vertically) in the middle of front baffle?
  • What the right place of the center port? Numbers on picture (9 5/64 and 10 27/64) are wrong. What are right ones?

If you want I can send you my Google sketch up file.
Thank you,
Vlad


Voldemar1 said:
Sorry
Forgot to attach picture.

I think what you're seeing within Sketchup is the measurement marker being off the edge a bit.

Not that it matters, but I had the top and bottom pieces running the full width (8.5"). For me, this simplified cutting. Given that, here's the cut list:
* All pieces from 0.5" material.
* Ports are 0.75"x4".
* Front & Back: 8.5" x 21.5"
- Driver center loc: 3.75" from side & 6.5" from end, off center to avoid inter-chamber port.
* Interior pieces are all 4" wide:
- Top & Bottom: 8.5" (#2). Overlaps both sides. Front and back overlap these.
- Long side: 20.5"
- Side Between Ports: 7.75". Overlaps port walls.
- Side Port to Top: 11.25"
- Horizontal port walls: 6.75" (#3)
- Vertical port wall: 9".
- Bottom port extension: 1.5". Port wall overlaps end of this.
- Interior chamber port extension: 1.25. Port wall overlaps end of this.
* Suggest making back removable to allow stuffing adjustments.
* I doubled the amount of acousta-stuffing in driver chamber to mellow ripple.

Qs Answered:
The driver can be lowered some. The port exit may be too close to the driver. You want the sound to interact with the chamber before entering the port. You could try it in the middle (given sufficient clearance behind the driver), and maybe at 4"-4.25" to give the inter-chamber port more room. My driver height was chosen because of my ear height above my desk. The overall height/shape was chosen because I had room. If this shape doesn't work for you, it can be altered. It's the volumes that are more important.

The top of the "center" port is 11.75" from the top edge. Putting the top edge of the horizontal port wall that helps form that port at 12.5" down from the top.

That should help.
 
Voldemar1,

I have a few CHR-70's. I have not yet decided on the enclosure for them. Thank you for sharing your design. But can you tell me why should I want build this enclosure instead of a standard BR? A standard ported design will give me an F3 of about 37 Hz in a smaller less complicated box. What is the benefit of building your box? I am not asking this to be disrespectful of your design. I just want to understand how the benefits of this design justify the additional cost, complexity and size. In short, is it worth the effort and why?

Thanks,
Steve
 
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