Rolls DU-30B

I bough this item as I wanted the music volume to decrease when I was speaking, but soon I realized it is not possible to use it as I wanted.

Even if you have a lot of settings which configure the device my problems were the following:
- as soon you make a fsss... or breath stronger, the ducker effect starts and the music volume is lowered .... but this isn't my wish
- another problem is when you have longer pauses between words while speaking as this causes the music volume to increase and then again to decrease.

Of course that depending on exactly what you want to do, this item can be perfect for you.

so after much online searching it appears this is probably the only stand alone mike / music ducker available on the planet ! With only one video review currently available on u tube it was with some trepidation I purchased one ( thomann have an excellent returns policy by the way ).
A few years back I had an original ( not the inferior Chinese made versions) citronic sm450 dj mixer with built in Automatic mike talkover & it was superb with adjustable parameters I could be anywhere in the venue away from the mixer and perform my comedy dj act and not have to be worried about being drowned out by the music I would be playing 😀 move forward 20 + years and unless you can budget for a top of the range pioneer mixer there's nothing decent around that will do the job.... 🤔
I currently use an excellent Yamaha mg 12 fx mixer for live work - so I have just tested the rolls unit with a music source - connection is simple stereo rca in and out into your stereo mixer channel, then plug your chosen mike into the XLR input - after a little experimenting with the controls I achieved the level & time I wanted to reduce ( duck ) the music for clear mike sound BUT I wasn't happy with the audi quality on the microphone- there's just a volume control and no eq... here's MY SOLUTION use an XLR microphone splitter cable - one end into the rolls unit & the other into your regular mixer mike channel, then adjust the mike volume on the audio ducker so it still 'triggers' the unit but use your main (mixer) level & eq to what your happy with 😃 I've found this works excellent- music ducked to a level I'm happy with & my regular mike sound not impaired in any way 😀

Etant guitariste expérimental, j'ai tendance à utiliser un son de guitare et d'autres sons comme ma voix, des samples, des bruitages...
Un ducker est donc indispensable pour éviter un effet "bouillie" sonore. En fait il se comporte comme si vous aviez un petit ingénieur son qui s'occupe du mixage avec vous!
Il va baisser le volume d'un des signaux selon le volume d'un autre signal.
Exemple: je chante par dessus un air de guitare que je joue, l'air de guitare va passer à l'arrière plan très légèrement pendant que je chante, plus je vais chanter fort plus la guitare sera en arrière plan. En revanche, quand je vais m'arrêter de chanter la guitare va revenir naturellement à son niveau initial.
La progression de retrait et de retour peut également être réglé pour qu'elle soit lente ou très rapide.

Un gadget indispensable donc !