Does the QPAS have an ADC in it?

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nickerz
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Does the QPAS have an ADC in it?

Post by nickerz » Sun Apr 25, 2021 5:34 pm

So I'm having trouble getting information on the QPAS because Make Noise seems to be one of those companies that overly drapes their releases in marketing and lore, which is fine really. But I'm sensitive to knowing my signal path and generally don't introduct ADC's into it because I already run a hybrid setup. If it's doing something digital, that is the point I'd bring it ITB anyways. So my filter bay I want to keep analog.

They mention it's 4 "state variable filter cores." The use of the word "core" here seems ambiguous. So I suppose the quickest way to boil this down is does this thing have an ADC in it?

:sstorm:

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Re: Does the QPAS have an ADC in it?

Post by Stice » Sun Apr 25, 2021 5:55 pm

No. From the manual: ‘The QPAS is a 100% analog filter for musical applications and is not suitable for laboratory use.’

Filter core is pretty common terminology.

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Re: Does the QPAS have an ADC in it?

Post by colossus » Sun Apr 25, 2021 6:01 pm

You don’t even need to go to the manual. It literally says it’s analog on the product page.

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Re: Does the QPAS have an ADC in it?

Post by nickerz » Sun Apr 25, 2021 6:17 pm

colossus wrote:
Sun Apr 25, 2021 6:01 pm
You don’t even need to go to the manual. It literally says it’s analog on the product page.
I haven't found the description of analog to mean a whole lot these days. Literally every vendor is trying to do some form of hybrid tech to make a product cheaper. Isn't meant to slight Make Noise in specific, just a sign of how things are out there right now. Honestly wish I could trust an analog designation without any thought beyond that.

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Re: Does the QPAS have an ADC in it?

Post by KSS » Sun Apr 25, 2021 6:40 pm

I would send an email to MN directly. Or call and ask. The rest is guessing no matter what we say.
And I agree OP is wise to look into what's actually beneath the panel. If it matters to them.

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Re: Does the QPAS have an ADC in it?

Post by sduck » Sun Apr 25, 2021 8:16 pm

This got me curious, so I took a look at my qpas - here's a scan of the second pcb -
qpas.jpg
I'm just seeing the 4 filter sections, those chips are almost all TL072s with a 2164 for each section - all analog. The other pcb is much harder to remove, but i was able to poke around there also and don't see anything that looks like a DAC - it's just the same 072s and such.

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Re: Does the QPAS have an ADC in it?

Post by moremagic » Sun Apr 25, 2021 8:23 pm

thhey say its four filter cores because if they said it was four filters , somebody might think its got 4 channels

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Re: Does the QPAS have an ADC in it?

Post by KSS » Sun Apr 25, 2021 10:00 pm

sduck wrote:
Sun Apr 25, 2021 8:16 pm
I'm just seeing the 4 filter sections, those chips are almost all TL072s with a 2164 for each section - all analog. The other pcb is much harder to remove, but i was able to poke around there also and don't see anything that looks like a DAC - it's just the same 072s and such.
Thanks for the PCB photo, sduck! Clearly shows four 2164 analog filter cores

Based on the manual, I'd expect to see at least two more 2164s on that 2nd board. Or 4 13700's. One 2164 -or two13700- for the VC rez, and another for the input VCAs and 'housekeeping'.

Definitely no reason to suspect any need for digital.

--------------------------
Has anyone put a scope on the smile pass outputs? From the name and manual -along with TonyR's the making of txt I expect these are related to a shallow notch or inverted BP. Massaged by some feedback-CV. If anyone's done a deep dive here, I'd enjoy reading aout your results!

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Re: Does the QPAS have an ADC in it?

Post by starthief » Sun Apr 25, 2021 10:23 pm

I don't think there have been *any* cases yet where a Eurorack company lied about a filter being analog.

Delays are pretty much the only case where some might call it "analog" when it's got a PT2399 for instance, or other digital delay chip with an analog feedback path. A bad habit from the guitar pedal world. Assume any audio delay is digital unless it specifically uses a BBD, tape, an "oil can" etc.

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Re: Does the QPAS have an ADC in it?

Post by nickerz » Mon Apr 26, 2021 12:01 am

starthief wrote:
Sun Apr 25, 2021 10:23 pm
I don't think there have been *any* cases yet where a Eurorack company lied about a filter being analog.

Delays are pretty much the only case where some might call it "analog" when it's got a PT2399 for instance, or other digital delay chip with an analog feedback path. A bad habit from the guitar pedal world. Assume any audio delay is digital unless it specifically uses a BBD, tape, an "oil can" etc.
I'm still suffering from PTSD from trying to wade through guitar pedals and other things that have been digitally recreated for the last couple years. And to be fair, BBD is considered analog from guitar world. That's exactly why this thread is here though. So much guitar gear copy is a complete excercise to try and figure out if it's analog or digital. Sometimes just the controls are digital, sometimes some of the effect is digital but other parts are analog. Sometimes it's an "all analog signal path" but part of the effect is digitally created and put into the path (so it's doesn't hit a ADC)...

Just really trying to be careful. In guitar land since I've been going back to analog gear my tone and playing has improved dramatically. ;)

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Re: Does the QPAS have an ADC in it?

Post by drxcm » Mon Apr 26, 2021 1:16 am

I think BBD is considered analog in every world, not just the guitar world!

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Re: Does the QPAS have an ADC in it?

Post by moremagic » Mon Apr 26, 2021 2:25 am

ive had somebody argue that its not analog because the s&h circuits in the bbd are clocked & thus not continuous in the time domain, but it wasnt too convincing, given that clocking via an analog give continuous control over when the s&h's get clocked

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Re: Does the QPAS have an ADC in it?

Post by drxcm » Mon Apr 26, 2021 3:03 am

Tenuous at best .. there are a lot of analog processes that can generate “digital” signals. Eg gate = on / off, or a comparator, or analog logic. But digital gear implies something altogether different.

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Re: Does the QPAS have an ADC in it?

Post by notmiserlouagain » Mon Apr 26, 2021 3:13 am

I always found the digital/analogue demarcation line unhelpful, better would be hardware/software based...
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Re: Does the QPAS have an ADC in it?

Post by KSS » Mon Apr 26, 2021 3:28 am

notmiserlouagain wrote:
Mon Apr 26, 2021 3:13 am
I always found the digital/analogue demarcation line unhelpful, better would be hardware/software based...
I agree. I created a thread like this awhile back. I've ended up using "No uP, no firmware" as my reasonable line of distinction.

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Re: Does the QPAS have an ADC in it?

Post by R.U.Nuts » Mon Apr 26, 2021 4:24 am

moremagic wrote:
Mon Apr 26, 2021 2:25 am
ive had somebody argue that its not analog because the s&h circuits in the bbd are clocked & thus not continuous in the time domain, but it wasnt too convincing, given that clocking via an analog give continuous control over when the s&h's get clocked
It's true that BBD Chips are clocked and thus splice the analog input signal into discrete voltage values. But these values won't get converted into binary numbers. So there's no true AD/DA conversion involved with BBD chips. Hence they're called analog, which is true IMHO.
Furthermore guitar pedal manufacturers use terms like "analog style" or "analog voiced" if they're talking about digital pedals that emulate analog. If they're saying "analog" I'd take this for granted. If that's not the case I'd say that's a fraud.
But then there are Youtubers that say "this delay is analog" because it sounds like an analog delay even though the manufacturers clearly claims that the pedal is a digital emulation of analog or PT2399 based. But you can't blame the manufacturers for this.

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Re: Does the QPAS have an ADC in it?

Post by starthief » Mon Apr 26, 2021 8:19 am

moremagic wrote:
Mon Apr 26, 2021 2:25 am
ive had somebody argue that its not analog because the s&h circuits in the bbd are clocked & thus not continuous in the time domain, but it wasnt too convincing, given that clocking via an analog give continuous control over when the s&h's get clocked
Yeah, that's not what defines digital. If values are not being represented in a numeric (binary) form, it's not digital. Since BBDs use capacitors to store voltages, and the clock simply passes values from one to the next, that's definitely not digital.

...

I don't really get the OP's reasoning. In no way is every digital module in Eurorack already covered by some DAW plugin or Max patch or whatever. There are a few ports in VCV Rack, and Noise Engineering has some plugins (with, I believe, variations in sound and features compared to the hardware anyway). But show me the Shapeshifter or Odessa or Kermit mk2 VST plugin... :hmm:

Much less something that you suspect might be secretly digital based on no particular evidence. There's no QPAS clone plugin either!

Even where the sound is (theoretically) identical when running in a DAW vs. on dedicated hardware, the experience of using it is different, and thus the results. For a lot of us, that's the main reason we are into hardware.

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Re: Does the QPAS have an ADC in it?

Post by moremagic » Mon Apr 26, 2021 9:49 am

starthief wrote:
Mon Apr 26, 2021 8:19 am
moremagic wrote:
Mon Apr 26, 2021 2:25 am
ive had somebody argue that its not analog because the s&h circuits in the bbd are clocked & thus not continuous in the time domain, but it wasnt too convincing, given that clocking via an analog give continuous control over when the s&h's get clocked
Yeah, that's not what defines digital. If values are not being represented in a numeric (binary) form, it's not digital. Since BBDs use capacitors to store voltages, and the clock simply passes values from one to the next, that's definitely not digital.
nobody said it was digital, old boy was just real picky about what he considered analog continuity. as stated, the argument certainly didnt convince me, but there are people out there who dont consider bbd's to be entirely analog. of course, this was back when junos were generally not considered entirely analog either, so i wonder if that was related

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Re: Does the QPAS have an ADC in it?

Post by nickerz » Mon Apr 26, 2021 3:41 pm

notmiserlouagain wrote:
Mon Apr 26, 2021 3:13 am
I always found the digital/analogue demarcation line unhelpful, better would be hardware/software based...
That's why I asked if there's an ADC.

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Re: Does the QPAS have an ADC in it?

Post by nickerz » Mon Apr 26, 2021 5:23 pm

starthief wrote:
Mon Apr 26, 2021 8:19 am
moremagic wrote:
Mon Apr 26, 2021 2:25 am
ive had somebody argue that its not analog because the s&h circuits in the bbd are clocked & thus not continuous in the time domain, but it wasnt too convincing, given that clocking via an analog give continuous control over when the s&h's get clocked
Yeah, that's not what defines digital. If values are not being represented in a numeric (binary) form, it's not digital. Since BBDs use capacitors to store voltages, and the clock simply passes values from one to the next, that's definitely not digital.

...

I don't really get the OP's reasoning. In no way is every digital module in Eurorack already covered by some DAW plugin or Max patch or whatever. There are a few ports in VCV Rack, and Noise Engineering has some plugins (with, I believe, variations in sound and features compared to the hardware anyway). But show me the Shapeshifter or Odessa or Kermit mk2 VST plugin... :hmm:

Much less something that you suspect might be secretly digital based on no particular evidence. There's no QPAS clone plugin either!

Even where the sound is (theoretically) identical when running in a DAW vs. on dedicated hardware, the experience of using it is different, and thus the results. For a lot of us, that's the main reason we are into hardware.
I'm into hardware for fidelity which is why I'm building a hybrid setup. What I create is much lighter on soundscape than what I see most modular guys do so it works for me. I get the benefit of nearly unlimited sequencing options, map it to a midi controller and then send that into the real world, process it and back into my interface. I'm still working things out, but right now I'm working on my filter bank which is why I asked.

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Re: Does the QPAS have an ADC in it?

Post by natureclubcassettes » Mon Apr 26, 2021 6:13 pm

nickerz wrote:
Sun Apr 25, 2021 6:17 pm
colossus wrote:
Sun Apr 25, 2021 6:01 pm
You don’t even need to go to the manual. It literally says it’s analog on the product page.
I haven't found the description of analog to mean a whole lot these days. Literally every vendor is trying to do some form of hybrid tech to make a product cheaper. Isn't meant to slight Make Noise in specific, just a sign of how things are out there right now. Honestly wish I could trust an analog designation without any thought beyond that.
Hello, and welcome to the Forum.

I have yet to come into contact with a Euro manufacturer that I thought was trying to mislead me, especially with regard to something being "analog" or not. Maybe take a step back from the sweeping generalizations. Was this something you had encountered a lot in the pedal world? Euro is still pretty niche and I doubt a manufacturer would get very far without someone calling their bluff, especially here on the forum. Moreover, I have never encountered this sort of bad intention in all my time in euro (almost ten years).

off topic, but to the OP: I hope this isn't intentional, but have you said your username out loud? Because it sounds like a slur in the English language. Maybe re-think that one? Really don't mean to be rude here. Good luck with your Euro research, and best regards :)

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Re: Does the QPAS have an ADC in it?

Post by dubonaire » Mon Apr 26, 2021 8:39 pm

natureclubcassettes wrote:
Mon Apr 26, 2021 6:13 pm
nickerz wrote:
Sun Apr 25, 2021 6:17 pm
colossus wrote:
Sun Apr 25, 2021 6:01 pm
You don’t even need to go to the manual. It literally says it’s analog on the product page.
I haven't found the description of analog to mean a whole lot these days. Literally every vendor is trying to do some form of hybrid tech to make a product cheaper. Isn't meant to slight Make Noise in specific, just a sign of how things are out there right now. Honestly wish I could trust an analog designation without any thought beyond that.
I have yet to come into contact with a Euro manufacturer that I thought was trying to mislead me, especially with regard to something being "analog" or not. Maybe take a step back from the sweeping generalizations. Was this something you had encountered a lot in the pedal world? Euro is still pretty niche and I doubt a manufacturer would get very far without someone calling their bluff, especially here on the forum. Moreover, I have never encountered this sort of bad intention in all my time in euro (almost ten years).
That's my experience too. The thing about euro modules is you can see the circuit boards, so I don't think any maker trying to do that would get very far anyway.

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Re: Does the QPAS have an ADC in it?

Post by studioutopia » Mon Apr 26, 2021 9:41 pm

Not to make sweeping generalizations - but there is a common perception in the guitar pedal world that guitarists are not *very technical*. There is a bit of a belief in hocus pocus/voodoo stuff. And there are a lot of examples of fraudulence and misrepresentation. Some examples:
- That certain old capacitors exhibit magical tone - regardless of specifications or what a scope can tell.
- The distrust that certain manufacturers breed by gooping black epoxy all over a PCB to hide a.... let's face it... a really simple overdrive circuit (ARP did this too, if I remember correctly, to obscure a ladder filter design?)
- That aforementioned pedal, has mystical qualities - something Josh from JHS made fun of by listing his serial #4 on Reverb for $500k.Sooooo good....hahaha
- There were even a lot of amps in past decades that had big wooden cases and ventilation grills - passed off as tube amps. Yet they often had no tubes - or only had 12AX7 tubes in the preamp section (see: "Chocolates may contain lark's vomit").
I would agree, there is some magic in nostalia, heritage, classic aesthetics. I have several classic Fenders and Rickenbackers - and they bring me warm fuzzys.
But back to the Digital vs Analog discussions... yes. There have been many experiences in the guitar community of pedals being passed off as analog BBD delays, only to find out there was a PT2399 in there.
I have not experienced this to any harmful extent in Euro. I think largely due to the technical nature of its users and that the PCB is not hidden - as someone pointed out. I have seen a few attempts at obscuring circuit designs (most likely not to be malicious).
1/3 of my modular system is digital. It doesn't bother me at all. Although I do prefer my oscillators and filters to be analog - probably more of a "analog soul" thing. Interestingly - while my analog oscillators are far from the stability of a VST instrument with temperature drifts and other minor instabilities, my two digital oscillators have their own quirks - and those quirks don't impart the same musical and lovable character that the analogs benefit from.
I am generally not into Make Noise modules... but...
QPAS is a fantastic filter. I've had it for a year and a half. It has some mystique to it and some very unique behaviours. It can and will surprise you. Along with LXd, it will never leave my system.

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Re: Does the QPAS have an ADC in it?

Post by ari ellis » Mon Apr 26, 2021 10:03 pm

Without wanting to stan too hard, rest assured that Make Noise didn’t get where they are by lying about the architecture of their products.

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Re: Does the QPAS have an ADC in it?

Post by nickerz » Mon Apr 26, 2021 10:15 pm

natureclubcassettes wrote:
Mon Apr 26, 2021 6:13 pm
nickerz wrote:
Sun Apr 25, 2021 6:17 pm
colossus wrote:
Sun Apr 25, 2021 6:01 pm
You don’t even need to go to the manual. It literally says it’s analog on the product page.
I haven't found the description of analog to mean a whole lot these days. Literally every vendor is trying to do some form of hybrid tech to make a product cheaper. Isn't meant to slight Make Noise in specific, just a sign of how things are out there right now. Honestly wish I could trust an analog designation without any thought beyond that.
Hello, and welcome to the Forum.

I have yet to come into contact with a Euro manufacturer that I thought was trying to mislead me, especially with regard to something being "analog" or not. Maybe take a step back from the sweeping generalizations. Was this something you had encountered a lot in the pedal world? Euro is still pretty niche and I doubt a manufacturer would get very far without someone calling their bluff, especially here on the forum. Moreover, I have never encountered this sort of bad intention in all my time in euro (almost ten years).

off topic, but to the OP: I hope this isn't intentional, but have you said your username out loud? Because it sounds like a slur in the English language. Maybe re-think that one? Really don't mean to be rude here. Good luck with your Euro research, and best regards :)
It's pronounced like the english word for pants and I've had the name before the internet race wars of 2021. Since idk... since ISDN?

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