Synth-DIY Yahoo! Groups Archives

Thread

Quantizer delay: test results

2003-02-16 by peff2cv <m_2_f@hotmail.com>

Ok, folks, I have been reading the continuing quantizer thread(s) and
decided to settle it once and for all, at least scientifically...

I pulled out the oscilloscope and there IS both a delay and slew
(portamento) effect imposed by the QTKB. I initally set the TKB up to
alternate between min and max pot settings between stages and ran it
with a DTG at various speeds.

Results:

Delay: the QTKB adds an average 2-3 millisecond delay between input
and output.

Portamento: this is nonlinear so it's hard to quantify in ms/v but I
measured it takes ~10 ms to slew between values. The QTKB seems to
output a new value at ~2 ms intervals so there are bigger
"stairsteps" between TKB stages as you increase the pot values
between 2 stages. But, there is definiately a zippering portamento
thing going on here.

That's the view from the lab. I leave the debate as to the musical
implications up to you, the composers. I personally have no beef with
delay, but would like to see the portamento eliminated or minimized.

cheers,

Peff

Re: Quantizer delay: test results

2003-02-16 by Chris Whitten

> I personally have no beef with
> delay, but would like to see the portamento eliminated or minimized.

I totally agree with you.
I haven't noticed a delay but the portamento is extremely annoying.
CW

Re: Quantizer delay: test results

2003-02-16 by jan-hinnerk.helms@t-online.de

Thanks to Peff for the measurements!

That leaves me with one last QTKB question (yes, and then I won't
mention this again, promised): do its TKB OUTPUTS carry an already
quantized signal or are they just "thrus" for the unquantized TKB row
outputs?

Regarding a quantizer without portamento, please see
http://www.analogic-acs.com/quantizer.html
The 5 microseconds slew time for quantization quoted there for the
Quantizer prototype should really be quick enough, and it already has
banana jacks. Gur Milstein is the guy behind the project, regarding
availability he recently wrote to me:

Show quoted textHide quoted text

> we are cheking the posubilty to make a batch of the
> TM-116 pcb's to offer also kit's , i would let you
> know more detials as soon as i know more .

I keep my fingers crossed. Also for his sequencer project, which looks
like a nice row expansion to a TKB.

Best regards,
have a nice start into the week
Jan-Hinnerk

Re: Quantizer delay: test results

2003-02-16 by John Papiewski

The TKB outputs on the quantizer are already quantized. If you want
unquantized outputs use the regular outputs on the TKB itself.

jan-hinnerk.helms@... wrote:

Show quoted textHide quoted text

> Thanks to Peff for the measurements!
>
> That leaves me with one last QTKB question (yes, and then I won't
> mention this again, promised): do its TKB OUTPUTS carry an already
> quantized signal or are they just "thrus" for the unquantized TKB row
> outputs?
>
> Regarding a quantizer without portamento, please see
> http://www.analogic-acs.com/quantizer.html
> The 5 microseconds slew time for quantization quoted there for the
> Quantizer prototype should really be quick enough, and it already has
> banana jacks. Gur Milstein is the guy behind the project, regarding
> availability he recently wrote to me:
>
>
>>we are cheking the posubilty to make a batch of the
>>TM-116 pcb's to offer also kit's , i would let you
>>know more detials as soon as i know more .
>
>
> I keep my fingers crossed. Also for his sequencer project, which looks
> like a nice row expansion to a TKB.
>
> Best regards,
> have a nice start into the week
> Jan-Hinnerk
>
>
> To unsubscribe from this group, send an email to:
> SergeModular-unsubscribe@yahoogroups.com
>
> Keep on Patchin'!
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

Re: Quantizer delay: test results

2003-02-17 by Joe Pavone

Hello all.... sorry I didnt jump into this sooner. I have noticed the
problem with the quantizer, and it did not bother me much until I was
feeding the QTKB outputs into an ASR... The delay from th quantizer can
really screw you up here. I talked to Rex about it at length and he felt
that the quantizer was not the best design and that was it's normal
behavior.

My solution was to use 2 doepfer quantizers on the side in a small
cabinet and forget the QTKB. The Doepfer, like the AS quantizer, has a
gate in and out and since you feed a gate into these quantizers, and
they then give you a gate out... you just dont have these problems.

Rex suggested that an aditional sample and hold between the qtkb and the
asr, but that would also reqire some sort of gate delay that would fire
slightly after the main clock driving the TKB to catch the notes after
they have settled from the Qtkb output. Seemed like alot to go
through... I suggested to Rex that he re-disign the quantizer and add a
gate input.... we chuckled about this for a while.....

....jp

peff2cv wrote:

Show quoted textHide quoted text

>Ok, folks, I have been reading the continuing quantizer thread(s) and
>decided to settle it once and for all, at least scientifically...
>
>I pulled out the oscilloscope and there IS both a delay and slew
>(portamento) effect imposed by the QTKB. I initally set the TKB up to
>alternate between min and max pot settings between stages and ran it
>with a DTG at various speeds.
>
>Results:
>
>Delay: the QTKB adds an average 2-3 millisecond delay between input
>and output.
>
>Portamento: this is nonlinear so it's hard to quantify in ms/v but I
>measured it takes ~10 ms to slew between values. The QTKB seems to
>output a new value at ~2 ms intervals so there are bigger
>"stairsteps" between TKB stages as you increase the pot values
>between 2 stages. But, there is definiately a zippering portamento
>thing going on here.
>
>That's the view from the lab. I leave the debate as to the musical
>implications up to you, the composers. I personally have no beef with
>delay, but would like to see the portamento eliminated or minimized.
>
>cheers,
>
>Peff
>
>
>

Re: Quantizer delay: test results

2003-02-17 by Chris Whitten

> I talked to Rex about it at length and he felt
> that the quantizer was not the best design and that was it's normal
> behavior.
>
> My solution was to use 2 doepfer quantizers on the side in a small
> cabinet and forget the QTKB.

Quite ironic, as the usual line out of STS is that Serge modules are
incredibly high spec and can't be surpassed by other makes.
I'm of the opinion that the PSU isn't as bomb proof as claimed also.
CW

Re: Quantizer delay: test results

2003-02-17 by DarkStr717@aol.com

I can't hear any of this in my compositions so i guess this debate has little
value for me. Personaly i just don't care about test results. When it comes
to music I've always trusted my ears as the final "test" device.
Kind regards
John DuVal

Re: Quantizer delay: test results

2003-02-17 by Chris Whitten

> I can't hear any of this in my compositions so i guess this debate has little
> value for me.

I've heard slewing.
No need to test.
CW

Re: Quantizer delay: test results

2003-02-19 by metafoetus2002 <jan-hinnerk.helms@t-onli

--- In SergeModular@yahoogroups.com, Chris Whitten <cw.chris@z...> wrote:

Show quoted textHide quoted text

> Quite ironic, as the usual line out of STS is that Serge modules are
> incredibly high spec and can't be surpassed by other makes.
> I'm of the opinion that the PSU isn't as bomb proof as claimed also.
> CW

Hi Chris,
can you please be so kind and clarify on your PSU concerns?
Thanks in advance
Jan-Hinnerk