RS52AN-8 Break-up Suppression . . .

Steve_Lee

That peak at 12KHz . . . is it a harmonic event, mechanical or what?

Can I flatten it with DSP or does it need a passive notch?

tktran

If you’re talking about the peak above shown here:

Reference:

https://hificompass.com/en/speakers/measurements/dayton-audio/dayton-audio-rs52an-8

You can take care of it with DSP.

You can take care of it with a passive notch filter in parallel with the driver.

You can take care of it with a passive notch filter in series with the driver input. This has added advantage is that it will also suppress the harmonic distortion components marked in blue and purple below-

This has been done for many years but recently documented by Lars@Purifi

Reference:
https://purifi-audio.com/blog/app-notes-2/low-distortion-filter-for-ptt6-5x04-naa-11

Steve_Lee

"The RS52ANs sound considerably cleaner and more open when suppressing the top end breakup, even if its well outside the passband after the crossover"

From post #249 --> https://www.diyaudio.com/community/threads/the-dome-midrange-thread.407105/page-13#post-7565435

DSP won't fix that . . .

Steve_Lee

DATS V3 data for two current production RS52AN-8 mid domes after 48 hours of break-in at 325 Hz attached at link below - link good until 1-20-24 for those interested.

https://we.tl/t-LilFJ8IANw

tktran

Hi Steve,

I can’t seem to access those files.

Do you mind posting screenshots of what you see in DATS?

Please show a zoomed impedance trace, eg. Y axis of 10 ohms.

Windows Key-Shift-S to do screenshot.

Steve_Lee

Thanks for checking-in, Thanh.

Steve_Lee

Z data in .txt export:

Steve_Lee

Fumbling around with on line calculator using opposite notch filter terminology

Steve_Lee

They [RS52AN-8] sound hissy & dull compared to the HiVi DMB-A's even when employing PEQ & killing all freq's above 4KHz and using steep XO slopes, so DSP cannot fix the SQ and it appears to be a resonance problem. [lending credence to Wolf's prior admonition(s) concerning resonance damping with passive components].

tktran

Hmmm.

The impedance plot suggests that there are two resonances:

This seems to similar to the one detected around 2020:

With this frequency response:

Please read this post; accounting for difference between the early production run circa 2008:

https://www.htguide.com/forum/forum/primetime-a-v/mission-possible-diy/driver-testing-discussion/32744-driver-evaluations-for-a-new-project?p=833366#post833366

And this post; documenting the change:

https://www.htguide.com/forum/forum/primetime-a-v/mission-possible-diy/driver-testing-discussion/32744-driver-evaluations-for-a-new-project?p=833367#post833367

This certainly complicates the issue…

jr@mac

PE never addressed that issue, either. Not to my knowledge, anyways. Pity - those mids have so much potential.

Wolf

Steve, that is a parallel notch, as the parts are all in parallel with each other.

Steve_Lee

I think I will see if I can send them back to PE for a refund and get some other domes instead.
Life is too short to waste on broken toys . . .

Steve_Lee

Thanh - thanks again - you are consistently helpful and educational.

tktran

Steve,

If they are relatively new, I certainly hope they will.
Actually, even if they aren’t new, It certainly doesn’t meet the advertised claims (spec sheet)

ugly_woofer

PE takes anything back.

Steve_Lee

Return request sent to PE this afternoon with a link to this ^ thread.
Purchased 2 months ago and only got around to testing them last week.
I was hoping that the RS52AN-8's low Fs and metal domes would outshine the HiVi DMB-A's sufficiently to make me use them with the Fountek NeoCd3.5H Horn ribbon tweeters but, alas - it was not meant to be metal on metal . . .

jr@mac

Hear anything back from them?

Steve_Lee

Got bounced around for a bit but they issued a Return authorization this morning and will send a return shipping label shortly.

Thanks for asking, JR.