Hi All,
If I pan any track hard left or right and send to the reverb effect, the reverb is dead center.
Is it normal for the A4MKII reverb to sum to mono?
Hi!
I think the signal path until the amp page is entirely in mono. There it gets sent to the Reverb, but also to the panning AFTER that. So I think it’s not “stereo” before that.
(Anyone) Please feel free to correct me if my understanding is incorrect or incomplete.
The signal diagram in the appendix shows the effects sends coming after the pan.
The effects are digital, so my concern is that this is a firmware problem.
There’s also an issue with the delay sending both the dry and wet signals to the reverb, rather than just the wet, so you end up with the dry signal being sent to the reverb from both a track’s Amp page and from the delay page. I’ve reported this in a ticket already but never heard back.
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Afaik there was something about the return effects signal carrying dry audio as well when you send tracks through the individual outs and effects through main out only on the Analog Keys.
So they might not be 100% wet.
Or was that only with the external inputs?
I think almost all reverbs do this. Even if they have a stereo input, the nature of reverb doesnt have “panning”. A real reverb will come from all around you even if the initial sound was made on the left or right side.
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I just checked the manual. Page 109 does describe it as you said and I just checked the A4 does seem to act like you described.
There are true stereo reverbs. It’s not so uncommon. And indeed weird, the signal flow diagram indicates fx sends after panning.
Yeah, I think it comes down to the complexity of the algorithm. Maybe the A4’s is quite basic. I’m still going to submit a ticket just in case.
Yeah, but those arent “true stereo”. More like dual mono. 
Then again, shouldn’t a dual-mono reverb give the impression of stereo just from panning?
I guess I might have confused some stuff…when you use the external inputs, you can’t get a 100% wet effects signal, but for the synth voices you can.
What do you mean? It’s been a while since I dabbled into that kind of stuff.
I think its one of those terms that are confusing. But a true stereo reverb is acting like a real physical space. And in a large hall, after the initial sound is made, the reverb will come from all around you. And that is the nature of reverbs. And “true stereo” reverbs have some internal crossfeed to emulate this.
So if you have a reverb that you can feed something only to the left channel, and the reverb will only come out of the left channel is more of a dual mono reverb lines. One for the left, and one for the right channel. As this is not “natural”.
And then you have the mono in, stereo out ones. Or those who sum left and right to mono, then feed the reverb.
I found out that i didnt really hear a difference between using some reverb pedals in stereo vs mono, so it was easier to use them as mono to save up on aux sends on my mixer.
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Thx! 
Btw, I’ve checked the fx on my AK and suprisingly chorus and delay retain the panorama, the reverb doesn’t.
Didn’t expect that.
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Great thread. TIL why stereo reverb appears to sum to mono. But it’s behaviour makes total sense.
A good test is to run the output into a daw and sum to mono there. If it’s “true stereo” as Thomaso described, with a high amount of cross feed, you’ll hear the stereo width decrease when when it converts to a mono source. The wide stereo width comes from the subtle left/right variations.
A dual mono reverb without any cross feeding won’t increase stereo width, but it’s still stereo in that it (or the input signal, at minimum) can be panned left/right.
Ticket submitted to Elektron. I’ll let you all know what they say. Thanks all.
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