EL70s have arrived!!

[planet10]

Using the typical kit us diyers use to measure T/S has us measuring on a different part of the T/S curves.

I am now convinced that if what we measure is close to the factory (measured using LEAP or LMS) then that just means that the T/S curves are closer to horizontal.

Dan Wiggins has talked about this forever. It really struck home when Mark measured a set of FE127eN i sent him. Measures attached are for the same driver(s) just measured with different kit (and likely different weather conditions)

It really leaves a coundrum as to which parameters to use when designing. I typically use the numbers from the factory.

Looking at my measured EL70 data, i do see that i am measuring Fs between 70 & 75. Did you say that the set you got were a set of protos?

dave

[CSS/XBL]

Hi,

Those were the original prototypes which also got quite a bit of play so it's possible that the Fs is lower. I think Dave's results from larger batches are probably pretty close. Not sure what we've used in calculating tuning but they generally sound great.

Bob

[tuxedocivic]

I got an Fs of 72hz. I meant the spec sheet says 64hz, but the impedance curve on the same spec sheet says 97hz. That is, if you define Fs as the impedance peak.

I consider an Fs within 10hz of factory spec to be very good, as I measure with low voltage, rather than factories use high voltage. Therefore I get a higher Fs usually. Like you say Dave.

So my enquiry isn't about my measured differences, rather the conflict on the spec sheet.

[planet10]

Now i see what you are talking about.

Not the wrong impedance curve, just that it didn't get grabbed when the graph was moved on the page, you can see that the start of th eimp curve is not at 0 (the document is over 10 layers in Illustrator).

I have fixed the doc and put it here. Bob can download and replace his. I have left the name the same so any external links should still work

http://homepage.mac.com/planet10/CSS...ata-080909.pdf

Thanx for the QC Ryan.

dave

[tuxedocivic]

Perfect! That now makes my measurements very close. Even that resonance around 600hz. Mine is about 700 iirc.

[CSS/XBL]

Thanks Dave, I'll upgrade the file shortly.

Bob

[fakeout]

Downloads

Is that the link to a ton of downloads? I only see 13 plans for the EL70. OK, I don't mean to be cold, just that I don't see many compact designs.

[planet10]

The EL70 excels in larger boxes. Half MicroTower (microTower for that matter) and mMar-KEL0 are pretty small.

Some of those 13 plansets have more than 1 design (7 in the Lake District). It also works (very well) in Frugel-Horn Mk3.

p10 hifi | Box Library / CSS

One thing missing is the CGR Mar-Kel70.

And then there are the paid plans, which include updated Mar-Kels (including 2 versions of the floorstander) and Maeshowe (it is not small).

dave

[chrisb]

fakeout:

I doubt anyone has heard every single enclosure to which this driver is well suited, but I have heard a few myself - if you have the floorspace, the Castle version of micro-tower is a knock-out with dual EL70s per side. If size is an issue, the most compact enclosure that I'd recommend for them would be :


http://homepage.mac.com/tlinespeaker...map-231009.pdf

The larger Mar-Kel70 is definitely a better performer, but not easiest for a first build

http://creativesound.ca/pdf/Mar-Kel7...map-110410.pdf

[fakeout]

Thanks for the suggestion. I realized I could maybe accomodate the Mar-Kel70 by putting them under my monitor (like having a board on top of the speakers to support the monitor instead of having them right underneath the monitor which would require even smaller cabinets). (I have one computer where I stand up so my monitor is close to my head.)

I feel like experimenting with even smaller designs though, who knows, maybe try various designs with cardboard although I'm not sure it will give me a real clue as to what the sound would be with birch plywood. In any case, I know I don't want to bother my neighbor too much with Earth-shattering bass of a large back loaded horn or something like that. I once heard him yelling out loud (through the walls) that he had no control over cocaine. You never know what this guy might do when he's "emotional". lol, not that I don't think I can handle the guy, just that you'd never know what he'd be capable of...