Scan-Speek 4" for 49 cents?

[Æ]

Re: Scan-Speek 4" for 49 cents?

Alternate thread title: I'm a cutter now!

I've been trying out driver modifications on some old NSBs.

I like what you did, experimentation and hardly expensive or risky at that.

[jbruner]

Re: Scan-Speek 4" for 49 cents?

yeah. get a brass or copper washer

When I need a copper washer, I hammer a penny to the right size and drill a hole in the center. Much cheaper.

[jbruner]

Re: Scan-Speek 4" for 49 cents?

There isn't much copper in a penny these days :p

It was a 1963 penny. The 2011 penny achieved a 10k Le of .216
Anything before 1982 is good.

[Sidi]

Re: Scan-Speek 4" for 49 cents?

yeah. get a brass or copper washer

[killa]

Re: Scan-Speek 4" for 49 cents?

There isn't much copper in a penny these days :p

[jbruner]

Re: Scan-Speek 4" for 49 cents?

How about trying a copper pole piece?

That would be great if you mean a copper-clad pole piece.
However, I put a penny on the pole piece of sample 3 and measured.

Blue is original, red is penny


Inductance @10k dropped from .229 to .212 -this was very consistent.
Frequency response was essentially unchanged. Distortion was pretty much the same except for 3rd and 5th order which saw one or two dB improvement.

[fatmarley]

Re: Scan-Speek 4" for 49 cents?

How about trying a copper pole piece?

[jbruner]

Re: Scan-Speek 4" for 49 cents?

I am willing to bet the revelators would still be smooth without the slits. Perhaps in the case of the revalators it is a marketing tactic to drive up the price :eek: While they are great drivers the slit cone may not be the reason. If it is these slits might also improve the seas driver.

I'd take that bet. I'd say they are definitely smoothed by the slits.

Compare the 4db peak on the slit Revelator


to the 10dB break-up on the state-of-the-art non-slit Illuminator

[dlr]

Re: Scan-Speek 4" for 49 cents?

Since the slit cone has such a huge affect I would think the compound used to seal the slit back up would also have a huge affect. I would shoot for something that gets hard but stays flexible. Iwouldn't think a compound that stretches easily would work well as the slits would try to seperate and cause the cone to deform under stress.

Yes, my suggestion for this is sold by PE, "The Wet Look", what I've used in my testing. I believe it to be the same compound as (or very similar to) what is used by driver manufacturers when they apply an application to the diaphragm/surround interface.

dlr

[winslow]

Re: Scan-Speek 4" for 49 cents?

Like vulcanized CA glue...

Since the slit cone has such a huge affect I would think the compound used to seal the slit back up would also have a huge affect. I would shoot for something that gets hard but stays flexible. Iwouldn't think a compound that stretches easily would work well as the slits would try to seperate and cause the cone to deform under stress.

[Tin_Ears]

Re: Scan-Speek 4" for 49 cents?

I probably need to stop at this point and clarify my intentions.

I do not intend to try every questionable method of driver modification. I am willing to humor your suggestions because I love you all so much I just want to scratch you behind the ears, but the next phase will focus on proven methods of actual improvement. I've done mass dots, paint, coatings, and holes in the dust cap. Usually those things create more problems than they fix.

I wanted to find out if the well-known slit-cone method had any drawbacks. Could you damp the out-of band resonances without hurting the Clarity, Liveliness, Immediacy, Transparency?

Why, yes, Yes you can!

So the bottom line here is that the 2 slit samples are listenable. I have actually been playing them for days. That is the true test-can you stand to listen to it. I cannot tolerate the stock speaker or the 2 coated samples. I'm sure the slit samples will provide for much easier crossover design, too.

Well, you certainly made my little doggy head tilt and tail wag. I look forward to seeing your other tests. I have a few extras of these you can have if you need them to complete your testing.

[killa]

Re: Scan-Speek 4" for 49 cents?

Since the slit cone has such a huge affect I would think the compound used to seal the slit back up would also have a huge affect. I would shoot for something that gets hard but stays flexible. Iwouldn't think a compound that stretches easily would work well as the slits would try to seperate and cause the cone to deform under stress.

[J Fallows]

Re: Scan-Speek 4" for 49 cents?

I thought that you were going to wait until tomorrow to sink my battleship.
Anyhow, it's really interesting to see the test results.
Nice work and Thanks.

[jbruner]

Re: Scan-Speek 4" for 49 cents?

I probably need to stop at this point and clarify my intentions.

I do not intend to try every questionable method of driver modification. I am willing to humor your suggestions because I love you all so much I just want to scratch you behind the ears, but the next phase will focus on proven methods of actual improvement. I've done mass dots, paint, coatings, and holes in the dust cap. Usually those things create more problems than they fix.

I wanted to find out if the well-known slit-cone method had any drawbacks. Could you damp the out-of band resonances without hurting the Clarity, Liveliness, Immediacy, Transparency?

Why, yes, Yes you can!

So the bottom line here is that the 2 slit samples are listenable. I have actually been playing them for days. That is the true test-can you stand to listen to it. I cannot tolerate the stock speaker or the 2 coated samples. I'm sure the slit samples will provide for much easier crossover design, too.

[jbruner]

Re: Scan-Speek 4" for 49 cents?

I doubt the thick stripes of flexible glue will be nearly as effective as the slits.

Yeah, 3dB of break-up suppression doesn't compare to the slit samples that both supplied 11dB down.

The worse news is that instead of enabling me to listen through to the music, the stripes veiled the sound so heavily that it sounded like it was in thick mud, totally ruining the pace, rhythm and timing.

Sample 4 is now garbage.




Blue is original, Green is edge only, Red is stripes and edge glued.