here i check pulsar modular mdn p455's dual mono frequency response and you can see the left and right channels are the same...


but when i check the mid/side frequency response...


wow...that is sum difference !

let's see what this blue trivial pursuit game piece button does when i turn it off...


oh...there is no difference anymore.

there is also same sum difference with the saturation, sample pixs attached showing with grapefruit slice button on/off.

that is sum plugin...

Instead of making posts that get no replies and then reposting the same post, why not go to the dedicated product thread in 'products older than 2 months' and post your findings for the developer to see?

If you've found a bug, wouldn't it be better for users if the developer was aware?

Analysis is forbidden in the new products forum, the rules say to post plugin analysis here. I posted last time here and had my thread moved to gear shootouts for some reason, asked several times to have it moved back and got no reply. So i did it myself.
This is not a bug, just an example of a plugin using mid/side summing and processing.
There was discussion of the stereo image being effected (good and bad opinions) so I wanted to show what is happening.

Yeah, the new rules are quite prohibitive

Personally the 'I did the plugin doctor thing and the knobs on this classic eq don't match the actual frequency' (ignoring the hardware didn't either) etc posts get old. I like the 'no plugin doctor' in product posts rule. More discussion of actual use cases, less weird or in the weeds 'we got em boys' posts.

A separate post like this discussing those things for people who care about them just makes more sense to keep useful discussion going. So many people on this site want to use the eyeballs coming to a thread as their personal army to spam their personal pet peeve that should really just be a single post or a support ticket or them choosing to pass on a product.

In this case HighKoalaTea has called this developer all kinds of names, Koala said they aren't wasting their time when asked to submit a ticket if they think it is an issue, and posted to other of the developer's products to continue to post about a different product and call the developer names when they didn't get the response they wanted. That's not a good faith effort that ads to the community, and the results of the rules (oh no's, a new thread had to be made, that's what, 6 clicks) doesn't seem 'prohibitive' but productive. If people care, the new thread gets traction and can focus way better on the issue raised than commingled within a 'new product' thread.

Here I shared an audio example of this plugin/setting and how the stereo image can be effected.
https://gearspace.com/board/so-much-gear-so-little-time/990549-high-pass-filter-phase-issues-post16968128.html

This particular setting has the most significant M/S difference. None of the others have such a "mis-match" of M/S HPFs. They still have different freq response for M/S and side level boost.

Saw discussion again of how this plugin alters stereo image so I bump this in case anyone wanted some real answers to why...
(really wish I could post there :()

Well if that's why it sounds that way, makes sense I guess.

I said what I found out in that thread the other day, to me activating the "stage focus" button simply f's up the sound. I am surprised MDN and the Pulsar team think anything sounds better with it on. It's a head scratcher for sure.

I guess some people just don't mind massive sound sucking black holes in their stereo image and find them cool, or they just can't hear them, idk.

I still think the plugin sounds great without the "stage focus". It is just not a "spatial revelation" plugin as it markets itself.

Try the Silver Bullet plugin and the aspect ratio button, I find it's not too aggressive with the stereo image.

Yeah, it's a nice "betterrizer".

the infamous blue button has made its way onto the new pulsar modular mdn p821 tape plugin...

the input for this test was a sine sweep @ -15 dbfs pk / -18 dbfs rms.
it is on the left channel only, thus being equal in the mid & side (-21 dbfs pk).

blue button off:
mid = -17 dbfs pk, side = -16.1 dbfs pk

blue button on:
mid = -17 dbfs pk, side = -14.7 dbfs pk

The "widening" in p821 is just a simple gain boost of the side channel. When checking the crosstalk, the only real difference (aside from error noise) is that it's polar inverted.
If I level match the mid & side, they will null to the level of the "error"/noise, in this case about 16 bit +/-.

Apparently things got too reel on the p821 product thread and my posts were removed and I was banned. I will continue to post stuff here for anyone interested.

i would post this in the mdn p821 thread, but i can't, so...since this has to do with the "blue button", might as well do it here.
even though you turn it off, it's still on, so you can use these figures to compensate.
i tested using several different sources and these figures seem to be the general consensus for the difference of mid/side. since there is an element of "randomness" that limits the accuracy for measurement of peak values, these figures are approximate (truncated) but very close. also, i don't know too many mid/side gain utilities that have the numerical precision to match, so it would be pointless. i was able to get cancellation down to the level of "randomness" when level matching mid/side (approx 16 bits). I tested with this post p821. you should try both and see what works best for you.

900/15
m/s diff = side +0.855 dB
900/30
m/s diff = side +1.084 dB
456/15
m/s diff = side +0.145 dB
456/30
m/s diff = side +0.076 dB

(*just to make sure it's clear...the measurements are the difference, so apply the inverse gain for compensation)

(*also, once you start clipping, the proportions get skewed, so you're on your own lolz)