Digital Volume Infinite Encoders slow and need many rotations. Why is that?

[DrSpan]

So today i measured my Dsp Volume Knob.

I takes 19….. in words Nineteen Rotations to go from absolute silence to maximum output.

Is it technically not possible to have a good Finite encoder where you can regulate volume in 1 rotation like it always was possible until
it became digital ?

 

[staticV3]

Digital Volume Infinite Encoders slow and need many rotations. Why is that?

Because it is poorly programmed.

 

[DrSpan]

Because it is poorly programmed.

It is great sounding tbh. And measurements here on the site are awesome. But this encoder gets me ….

My Motu also needs around 5-6 rotations from silence to max and its a very good interface.

I simply dont know how it works. Someone used the arguments when talking about my Dsp that is has a „fine“ adjustement

but in analog i never had this issue . So whats the technical issue-difference ?

 

[DVDdoug]

That's just a marketing/engineering choice. 19 revolutions seems excessive. I don't know what's common for steps-per-revolution but in home environments 1dB or 1/2dB steps should be enough resolution. In mixing & mastering you might want 0.1dB or 0.01dB resolution and that would need multiple revolutions.

Sometimes there is "acceleration" where quick movements make bigger adjustments than slow movements.

My Motu also needs around 5-6 rotations from silence to max and its a very good interface.

Inputs on an interface also need to cover a much wider range. You might be recording birds in a tree at a distance, or from a close-mic'd guitar amp or drum. And microphone sensitivity varies greatly with condenser mics typically being 20 or 30dB "hotter" than dynamic or ribbon mics.

 

[voodooless]

Encoders with few steps are cheap, so if you want a bit of resolution for the volume control, you'll need quite a few rotations. Then again, 19 seems very excessive. What product is that?

You can have encoders with more than a hundred steps per rotation easily. They would do the trick but are very expensive. Otherwise, a lot can be done in software. You can measure the speed of rotation and adjust the volume ramp-up accordingly. This will give an unnatural feeling though, which is probably why they didn't do that.

 

[DrSpan]

Encoders with few steps are cheap, so if you want a bit of resolution for the volume control, you'll need quite a few rotations. Then again, 19 seems very excessive. What product is that?

You can have encoders with more than a hundred steps per rotation easily. They would do the trick but are very expensive. Otherwise, a lot can be done in software. You can measure the speed of rotation and adjust the volume ramp-up accordingly. This will give an unnatural feeling though, which is probably why they didn't do that.

It is a Flex MiniDsp TRS (balanced)
That said, it is not specifically this device. I could change the Knob (that is a bit wobbly as it is) and have less rotations as i`ve done on synthesizers of mine.
However also my Motu Ultralite is not a lot better. It has a smaller knob but you still need 5 (or 6 cant remember) full rotations for the whole dynamic range.

The Motu goes in 1db increments , the Flex in 0.5db

So my question is i guess,

1) What is the limit of resolution you can achieve using todays "state of the art“ technology using one Encoder that has a Beginning and an End point like an Analog Volume potentiometer?

 

[RayDunzl]

So today i measured my Dsp Volume Knob

Ok, you made me look:

Mine, on the preamp, takes about 3 1/2 turns to go from 000 to 151.

 

[DrSpan]

That's just a marketing/engineering choice. 19 revolutions seems excessive. I don't know what's common for steps-per-revolution but in home environments 1dB or 1/2dB steps should be enough resolution. In mixing & mastering you might want 0.1dB or 0.01dB resolution and that would need multiple revolutions.

Sometimes there is "acceleration" where quick movements make bigger adjustments than slow movements.


Inputs on an interface also need to cover a much wider range. You might be recording birds in a tree at a distance, or from a close-mic'd guitar amp or drum. And microphone sensitivity varies greatly with condenser mics typically being 20 or 30dB "hotter" than dynamic or ribbon mics.

I think its predominantly because The Motu has much smaller diameter knobs to be honest. its easier to have faster rotation like this . Also it goes in 1db steps and the flex in 0.5

"In mixing & mastering you might want 0.1dB or 0.01dB“. i personally dont cause when i want to hear 0,1 db ,,, No if i am honest i cant hear 0,1 db difference in Loudness Level as in „Turn the Volume 0,1db louder“ and doubt 99% of people would hear that.
I can hear 0,2-0,5 differences on the Eq easily though when working but its different cause Eq changes the way is sounds ….. ok lost track here
Returning to the Subject ,

I will make it the aim of my life to find an Encoder that regulates the Volume with the Feeling my beloved but gone Spl 2Control gave me.
Not directly 1 on 1 comparable cause its analog i know but i am talking about replicating the ergonomy of a thing like that in the Digital realm.

 

[DrSpan]

Ok, you made me look:

Mine, on the preamp, takes about 3 1/2 turns to go from 000 to 151.

Hello.

What amp and what diameter is the knob ?

 

[RayDunzl]

What amp and what diameter is the knob ?

Krell KCT preamp

About an inch and three quarters, 45mm.

 

[DrSpan]

Krell KCT preamp

About an inch and three quarters, 45mm.

Thanks for the info.

Always wanted a Kav 300 integraded or its other brothers when i was younger.
But ironically now that i could finally afford it i ended up looking for amps so small i can hide under my desk and dont want a Krell cause its too heavy.
Life has an unbeatable sense of humor i admit

 

[TurtlePaul]

In addition to the 0.5 or 0.1 dB resolution, keep in mind that most digital encoders are able go to -99 dB while most old analog pots have terrible channel balance and inconsistent attenuation past -25 or -30 dB. If you did set the digital to only go to -25 dB with 1dB resolution it would fit in a single rotation.

 

[DrSpan]

In addition to the 0.5 or 0.1 dB resolution, keep in mind that most digital encoders are able go to -99 dB while most old analog pots have terrible channel balance and inconsistent attenuation past -25 or -30 dB. If you did set the digital to only go to -25 dB with 1dB resolution it would fit in a single rotation.

So i 0.5 the step resolution limit by todays standards? I am not up to date with these technical aspects tbh.

"most old analog pots „. i am talking about things like the Spl 2 Control. It did not sound like it had any issues. At least anything tha bothered me.
However i say a post of someone (i think here on this site but am not sure) that had done measurements with his Spl Volume 8 (which is what i would need if i applied a Volume controller on the outputs of the MiniDsp but then saw the channel discrepancies and it scared me off for now…….

Don`t know if it was Series related bad Quality control though

 

[voodooless]

It is a Flex MiniDsp.

That makes about 12 pulses per revolution, that is indeed quite a low number.

 

[Berwhale]

It is great sounding tbh. And measurements here on the site are awesome. But this encoder gets me ….

My Motu also needs around 5-6 rotations from silence to max and its a very good interface.

I simply dont know how it works. Someone used the arguments when talking about my Dsp that is has a „fine“ adjustement

but in analog i never had this issue . So whats the technical issue-difference ?

The unit needs to be programmed to respond to (rotational) velocity as well as position information from the rotary encoder. At low velocities, is should adjust the volume in small increments for fine control, at higher velocities, it should adjust the volume in larger increments for gross volume control. i.e. if you turn the knob quickly the volume changes a lot, if you turn it slowly the volume changes a little (for the same change in knob angle).

 

[TurtlePaul]

So i 0.5 the step resolution limit by todays standards? I am not up to date with these technical aspects tbh.

It is not the limit. device makers need to trade off fine grained control vs. how far the knob needs to be turned. I usually find 1 dB to be sufficient to get close enough to perfect volume but digital systems are precise to 0.1 dB or less if needed.

 

[MCH]

1) What is the limit of resolution you can achieve using todays "state of the art“ technology using one Encoder that has a Beginning and an End point like an Analog Volume potentiometer?

A Google search "single turn absolute encoder" gives plenty of 12 bit (4096 steps) and even saw 22 bit (way too many steps) encoders. I guess state of the art will be even more bits, and more $$$. Now you only need to find someone that builds you a volume knob with them.

 

[DrSpan]

That makes about 12 pulses per revolution, that is indeed quite a low number.

I asked over at their forum but got only „i never use the knob i used the remote“ or „its perfect the way it is“ so i gave up there.

The unit needs to be programmed to respond to (rotational) velocity as well as position information from the rotary encoder. At low velocities, is should adjust the volume in small increments for fine control, at higher velocities, it should adjust the volume in larger increments for gross volume control. i.e. if you turn the knob quickly the volume changes a lot, if you turn it slowly the volume changes a little (for the same change in knob angle).

A Google search "single turn absolute encoder" gives plenty of 12 bit (4096 steps) and even saw 22 bit (way too many steps) encoders. I guess state of the art will be even more bits, and more $$$. Now you only need to find someone that builds you a volume knob with them.

I don`t know how to interpret these results . Thats why i ask here. I cannot calculate what it means in the End consumer Device if you use 12 bit or 22bit resolution encoders.

I simply cant understand how nobody seems to bother about knobs that need multiple rotations to do such a trivial task that was so simple to do or decades and
did everything in one or less that one rotation in comparison. Its like being in a dream and no ones sees you hahahah
so i dont think i will ever get what i wish for so….‍

 

[voodooless]

A Google search "single turn absolute encoder" gives plenty of 12 bit (4096 steps) and even saw 22 bit (way too many steps) encoders. I guess state of the art will be even more bits, and more $$$. Now you only need to find someone that builds you a volume knob with them.

AliExpress shows about $€£ 25 for a 16 bit encoder, double for 18 bits. It’s not cheap but would resemble an analog volume pot very well. Since these things are build for high RPM usage, one should probably add some friction so it will actually stick to a position.

Obviously you can’t just jerry rig such a thing in a Flex. You could however probably find a drop in replacement for the Flex encoder with more pulses per revolution.

 

[DrSpan]

It is not the limit. device makers need to trade off fine grained control vs. how far the knob needs to be turned. I usually find 1 dB to be sufficient to get close enough to perfect volume but digital systems are precise to 0.1 dB or less if needed.

For me the first priority would be "1 Rotation" encoder and Secondly if it is in 0.5 or 0,1db increments