Input / Output Levels

I’m using an SSl SiX which allows for it’s master mix Send into the Mod Duo X and Return back to the mixer and out to speakers. This can be engaged on/off via a button on the master mix. If I wire it up where the Send goes straight into the Return and engage this signal path the result is the same signal.

However, if I put the Mod Duo X into this path and engage, the signal drops significantly in volume. This happens even with Bypass enabled on the Mod Duo X. The workaround is I have to use the Gain 2x2 which appears in the default pedalboard and crank it up to +12db to get an equivalent volume.

Is this correct? Is there a device wide volume setting that I am unaware of that can send the signal in and out at unity without the need for amplification?


I thought I had resolved this as I remembered a while back I reduced the Input / Output levels in the System menu. I went and changed them back to 0db but then the inputs were clipping even though the output on my mixer was not, so I went to the audio source and adjusted that until the input LEDs on the Duo X were not clipping.

At that point I then engaged / disengaged the send/return with Mod Duo X in it, and there is still a noticeable volume drop.

This seems to be just the way the Duo X works as I can’t see any other settings that would be causing this. Can anyone else chime in and let me know if this is their experience or not.

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Have you checked the output volume too? What I found that works best it a combination of both adjusting output/input level. I think that the scale of the dBs of the Duo is dBFS so getting it at 0 it’s really really high (line level in dBFS would be like -18). Try a combination of output, input and a gain plugin if that doesn’t work


Thanks @jesusperezsv.
@KidYoshiSan, as @jesusperezsv said, I believe that your issue is mainly related with gain staging. If the out of the mixer is not clipping, I would say that is only the gain staging inside the MOD DuoX.
My suggestion is mostly the same as @jesusperezsv said: reduce the input gain to a level where it doesn’t clip and compensate on the output gain as well to a non clipping level. If you still have a drop on volume, compensate on the return channel of your mixer.

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It’s also worth noting that it may also be a headroom issue — the SiX doesn’t clip until +27dBu. I’m not sure what levels the Duo X are happy with. @KidYoshiSan, how hot are you running your master mix?

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Thanks for the tips. The output on the mixer was just under 0db so it wasn’t being pushed beyond what the Duo X can handle. I’m unable to control the return level on the master as it goes out and back in at unity. The solution would be to lower the signal going into the Duo X and then boosting before it leaves the Duo X. The downside to this is I can’t use the bypass option as this results in a lower volume.


So if you want to use it, I would suggest you adjust the gains so it keeps the levels if bypassed or not.
Indeed a pity that you can’t control the gain on the return of the mixer. Isn’t it possible to return to a different channel?

While we’re on the subject of Input/Output levels, I’ve run across a weird problem. I’m using a Dwarf with my basses, and I’ve found that when using my Ibanez BTB 1206 (a 6-string) that has a preamp running at 18v, I’m hearing something overloading, especially on the low B string. the LEDs aren’t even in the yellow, but with headphones on it’s apparent that SOMETHING is being overloaded. I was using the BRIG:Direct.Shim pedalboard, so not a lot of gain structure there. I tried playing with some volume pedals to reduce the incoming gain which worked somewhat, but still unsatisfactory to my ears. There’s no way to lower the output level on the preamp that’s inside the bass guitar. Any idea why I’d hear an overloaded circuit somewhere in the Dwarf but no visual indicators?

Isn’t it possible that is on your headphones and the headphones volume is too loud for those “deep lows”?

No. I’ve found that I’m hearing this at very low input gain levels inside the MOD pedalboard. I used one of the volume pedals to reduce the gain going into the individual pedals; the distortion was there all the way down to -30dB on the gain pedal. Also, the headphones I use (Sennheiser HD280) normally handle low frequencies with no problem. I’ve used them in monitoring/tracking my bass before without trouble. I even switched headphones to be sure it WASN’T the headphones.

And when you play especially that string do you you have CPU and RAM spikes?

I don’t remember there being spikes in those areas. I didn’t have a lot of pedals so I wasn’t using a lot of processing resources. That’s why it was so weird to me to hear that happen.

I had issues with low B also.

For me turning down the input gain of the dwarf resolved it. It was only the initial attack of the note that was peaking, and happening so fast it didn’t trigger the input LEDs.

Hopefully you can also find something that works for you.


@Roachmanfwa do you mean before? So this issue appeared recently?

As I think about it, yes. I used the same bass at Christmastime and didn’t notice this problem.

Have you updated the device?

Yes. I did the day the update was available.

By the way, the other active basses I have don’t have a similar problem - they’re both 5-strings as well, but with 9v power rather than 18v preamps.

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Hmm that may be the reason.
How is the behaviour of that specific bass for example with a sound card (if you can test that setup)?

I’ve never had a gain/distortion problem recording with that bass. I’ve had this bass for close to fifteen years - never had this issue either live or in the studio.