intellijel Hex VCA

MrBiggs · Post by **MrBiggs** » Fri Apr 15, 2011 9:34 am

Started a new thread about these VCA questions so matttech can stay on-topic.

viewtopic.php?p=444539

I'm suddenly puzzled.

matttech · Post by **matttech** » Fri Apr 15, 2011 9:37 am

MrBiggs wrote: You mentioned in your first post that you are led to believe that Doepfer VCAs don't sound good. Which of course is goofy. If you're switching between Cwejmans and HexVCAs and A132-3s, then I suspect you might find some complaints. But when starting out with this stuff, get what you understand, get what's available, get what you can afford. Fretting about all the variations in theory is great masturbation and good for some schoolin' but really doesn't mean much until you plug in a cable.

2Ã‚Â¢

some good points made there, pretty much seconding what i was trying to say.

as with recording gear - digital to analogue converters, eqs, compressors, mic preamps and the like - there is often a lot of guff talked about how one product is "miles better" than another, when what we are actually talking about is minute differences in sound that, often, are merely that - "differences" (eg: one preamp may sound different to another, but which is "better"? - it ALL comes down to personal preference.....and this is EXACTLY why i have gone with a few different VCAs - i KNOW i'll need a load of them if i want to do multiple simultaneous lines (which i do), so my thinking was this: rather than just plump for one type, i may as well buy a selection second hand, then whichever i prefer stays....and i sell the others on at little or no loss

this way I get to make my OWN mind up based on real-life A/B-ing, as opposed to reading spec sheets and watching youtube videos.

and if i learn that actually there is very little to tell them apart....well, then that's a valuable lesson learned! (i learned that lesson VERY early on in my hi-fi purchasing days, when we did some blind listening tests between a Ã‚Â£2000 cd player and a Ã‚Â£200 one. nobody could tell which was which. i then made the decision to in future spend my money where it made the most quantifiable difference......)

VCAs excite me the least out of any of the modules, and my instincts tell me to put my money into more "creative" modules, but I do NOT claim to be an expert in these matters.....so in my mind it's prudent to make sure i am not tainting what is rapidly becoming a pretty expensive system through sheer ignorance. i am particularly interested in seeing how the different VCAs react to, say, the same envelope settings - after all we're not JUST talking sonic transparency or signal to noise here, so potentially there could be noticeable differences.

or not....time will tell.

plus, i love geeking out over such things!

matttech · Post by **matttech** » Fri Apr 15, 2011 9:41 am

MrBiggs wrote:Started a new thread about these VCA questions so matttech can stay on-topic.

viewtopic.php?p=444539

I'm suddenly puzzled.

hey man - don't get puzzled

i'm merely pontificating (and killing time at work until i get home to witness the birth of my REAL, rather than hypothetical, modular monster

)

i might actually be all "VCA-d out"

matttech · Post by **matttech** » Fri Apr 15, 2011 9:44 am

noisetheorem wrote:MrBiggs makes a lot of good points here. Coming from software and the Nord modulars, VCA's are very confusing, and the answers rarely satisfying.

In my mind, VCAs should be simple. Think of an attenuator, and a CV just controls where that knob is. But its not that simple. There is AC/DC coupling, offsets, response curves, whosits whatsits and thingamajigs, and it just seems the only way to find out what works is to buy them all and test them personally. That is frustrating.

or fun, depending what you're particular fetish is....

i'm starting to see my modular build almost in scientific research terms, but that will all change once it's going "dwwwwaaaargh, dwwwwaaaargh, thwippp...thwerpp, thwippp, thwerrrrp" and scaring small children

MrBiggs · Post by **MrBiggs** » Fri Apr 15, 2011 9:46 am

matttech wrote:
MrBiggs wrote:Started a new thread about these VCA questions so matttech can stay on-topic.

viewtopic.php?p=444539

I'm suddenly puzzled.
hey man - don't get puzzled

No not over anything you wrote. Puzzled by the A132-3 I've used thoroughly for 18 months...

matttech · Post by **matttech** » Fri Apr 15, 2011 9:52 am

MrBiggs wrote:
matttech wrote:
MrBiggs wrote:Started a new thread about these VCA questions so matttech can stay on-topic.

viewtopic.php?p=444539

I'm suddenly puzzled.
hey man - don't get puzzled
No not over anything you wrote. Puzzled by the A132-3 I've used thoroughly for 18 months...

one real bug-bear i have is crosstalk - and this is another reason why i want a few different products to test-drive. if i got, say, all a131's and they had noticeable crosstalk it would do my head in. but if i have 3 completely different products and they ALL have it, then you just have to go "that's the way it is then" and move on....

likewise, if they are all different and one has NO crosstalk and the others DO.....well that's ANOTHER valuable lesson!

ANYWAY......

ItÃ¢â‚¬â„¢s Friday, Friday
Gotta get down on Friday
EverybodyÃ¢â‚¬â„¢s lookinÃ¢â‚¬â„¢ forward to the weekend, dwwwwaaaargh, dwwwwaaaargh, thwippp...thwerpp, thwippp, thwerrrrp weekend
Friday, Friday
GettinÃ¢â‚¬â„¢ down on dwwwwaaaargh, dwwwwaaaargh, thwippp...thwerpp, thwippp, thwerrrrpFriday
EverybodyÃ¢â‚¬â„¢s lookinÃ¢â‚¬â„¢ forward to the weekend!
dwwwwaaaargh, dwwwwaaaargh, thwippp...thwerpp, thwippp, thwerrrrp

Dofkev · Post by **Dofkev** » Fri Apr 15, 2011 10:14 am

What I found surprising about the hex vca is how much it decreased the volume of audio signals. I only have experiance with a few other vca's, but they all atleast amplified audio signals somewhat. When an audio signal is applied to the hex vca, I can turn the respective offset knob 100% clockwise, and it might equal the level of the incoming signal, but it doesn't seem like it adds anything - It actually seems lower than the incoming signal.
Can anyone speak to this? Is there something wrong with my module?

Mitchk1989 · Post by **Mitchk1989** » Fri Apr 15, 2011 10:20 am

I think its supposed to be unity at full clockwise.

robotfunk · Post by **robotfunk** » Fri Apr 15, 2011 10:25 am

I don't know of any VCA that amplifies. Voltage Controlled Attenuator would be a better description than VC Amplifier.

Mitchk1989 · Post by **Mitchk1989** » Fri Apr 15, 2011 10:30 am

I think the malekko one amplifies in exp mode.

MrBiggs · Post by **MrBiggs** » Fri Apr 15, 2011 10:37 am

And apparently the newer SSM A132-3s amplify some as well, though they distort. This is according to Doepfer.

http://www.doepfer.de/a1323.htm

Doepfer wrote:This circuit is still in production and available without problems. The main difference between the old and the new version of the module is this: for the old version with CEM3360 the maximal amplification was limited to 1. Even if the control voltage is increased the amplification stucks at 1. For the new version with SSM2164 the amplification is not limited to 1. If the control voltage is increased even a higher amplification than 1 is possible. With a corresponding input level this may lead to distortion at the output because the output swing is limited to about +/-10V and clipping occurs. Amplification "1" is obtained at about position "8" (i.e. 3 o'clock position) of the manual control "Gain" for both linear and exponential mode.

But yeah, from what I understand the Intellijel's and most other VCA's don't add anything in volume. What you put in is what you get out at maximum clockwise.

ersatzplanet · Post by **ersatzplanet** » Fri Apr 15, 2011 10:42 am

The main problem with VCAs in general is that in the past they were not functionally the same. Filters, VCOs etc. all basically work the same whereas VCAs have been designed differently by different manufacturers. The EMS synthi line had VCAs combined with envelope generators (later emulated on the Nord Modular series) and E-Mu made VCAs that actually amplified the signals. In most cases the term VCA should mean Voltage Controlled Attenuators not Voltage Controlled Amplifiers since most VCAs only reach unity and don't amplify.
I used to teach Electronic Music at a collage here in WA and the concept of a VCA was always a problem to some. You always got the "why is the sound on all the time?" question. I ended up making it standard to point out that of all the modules on the system that the VCA is the one you have to turn off the gain, offset, level - whatever the control is labeled (turned CCW) and run it with a control voltage. Then the gain, offset, level whatever control make sense as "adding" to the CV.
I learned on a Arp 2500 and my first synth was a VCS3 so moving between those two systems meant re-learning A LOT of things. Modulars nowadays are much more like each other than they once were. For instance on a EMS rig there are NO input attenuators - all modules have output attenuation (or you use a pin with a bigger resistor in it).
AT least the modules available in Eurorack systems act similar to others in the same family.

-James

MrBiggs · Post by **MrBiggs** » Fri Apr 15, 2011 10:50 am

I hadn't even thought about the "always on" issue. That's what really killed me starting out. When I was still assuming the keyboard synth paradigm, I didn't understand that pressing a key is one way or another sending a gate signal that triggers an envelope that opens the volume up. This took a long time to make sense of the idea that the keyboard is a CV controller and a mere trigger/gate generator and a trigger/gate can come from almost anywhere. THAT is what made me go back to Reason and rethink everything about that software, and what made me find my "regular" synths so limiting.

hawklord2112 · Post by **hawklord2112** » Fri Apr 15, 2011 10:54 am

matttech wrote: i'm starting to see my modular build almost in scientific research terms, but that will all change once it's going "dwwwwaaaargh, dwwwwaaaargh, thwippp...thwerpp, thwippp, thwerrrrp" and scaring small children

this. very much so.

i will admit to having modules before case. and minicase before anything massively useful (thanks again to monobass for that). and a most unusual progression of modules.

the HexVCA is going to be in my case at some point. even if they arent "vanilla VCAs", the sheer density wins them points.
will admit though that this thread has opened my eyes to what it could do above volume controlling my dwwargh dwarrrgh thwipp.

ersatzplanet · Post by **ersatzplanet** » Fri Apr 15, 2011 11:01 am

MrBiggs wrote:I hadn't even thought about the "always on" issue. That's what really killed me starting out. When I was still assuming the keyboard synth paradigm, I didn't understand that pressing a key is one way or another sending a gate signal that triggers an envelope that opens the volume up. This took a long time to make sense of the idea that the keyboard is a CV controller and a mere trigger/gate generator and a trigger/gate can come from almost anywhere. THAT is what made me go back to Reason and rethink everything about that software, and what made me find my "regular" synths so limiting.

For most users the "A-HA!" moment comes when you tell them about the idea that almost all the knobs on a modular synth can be "turned" via a control voltage - that is when you see the minds working. I used to teach the functions of the hardware, manually turning knobs and such then drop the idea of CV on them when we hit EG and LFOs - I would replicate the knob turning with a CV and show them where the physical limitations would drop away with CV and that CVs can come from almost anything - once that idea sinks in you are hooked...
-James

hawklord2112 · Post by **hawklord2112** » Fri Apr 15, 2011 11:05 am

ersatzplanet wrote:once that idea sinks in you are hooked...
-James

hey - we're all hooked already.

Thonk Support · Post by **Thonk Support** » Fri Apr 15, 2011 11:17 am

noisetheorem wrote:MrBiggs makes a lot of good points here. Coming from software and the Nord modulars, VCA's are very confusing, and the answers rarely satisfying.

That's interesting actually.. cos i never used to use explicit 'VCAs' on the Nord Modulars, just route through the VCA that's hardwired to all the envelope types... but then when I did start using the simple properly modular VCAS on the Nord my patching got a hell of a lot better. I think the nord still protected you a little from that 'always on' thing with the built in routing (or normalisation as I call it now

)

intellijel · Post by **intellijel** » Fri Apr 15, 2011 11:21 am

Apologies about my website being not being up to date, I have been promising this and new manuals for weeks now but it keeps falling lower on the priority chain unfortunately.

Analogue Haven is by far my biggest distributor so they have all the most current information. On each module page there has a detailed description and often links to demo videos. I also have a vimeo and youtube page with video demos.

I started building a new website but simply have not had enough time to finish the porting and adding all the new content.

Also regarding availability of HexVCA: Post Modular UK and Schneiders Buero should both have stock (they received shipments this week) and I believe Analogue Haven still has some as well.

intellijel · Post by **intellijel** » Fri Apr 15, 2011 11:26 am

Dofkev wrote:What I found surprising about the hex vca is how much it decreased the volume of audio signals. I only have experiance with a few other vca's, but they all atleast amplified audio signals somewhat. When an audio signal is applied to the hex vca, I can turn the respective offset knob 100% clockwise, and it might equal the level of the incoming signal, but it doesn't seem like it adds anything - It actually seems lower than the incoming signal.
Can anyone speak to this? Is there something wrong with my module?

Full clockwise should be unity volume (no gain). If you are using the "SUM" output then there is a -6dB drop (to give more headroom for summing multiple signals).

However if your CV is higher than 5V then the VCA will amplify. You can amplify quite a bit but it will distort eventually.

The Azimuth VCAs are actuually configured for about +3dB gain when fully clockwise.

shacksman · Post by **shacksman** » Fri Apr 15, 2011 11:26 am

intellijel · Post by **intellijel** » Fri Apr 15, 2011 11:27 am

shacksman wrote:So when will these be landing in the uk ?

They are already there. Talk to David at Post Modular.... he only has 10 and I think they will go quickly.

sparks · Post by **sparks** » Fri Apr 15, 2011 11:34 am

intellijel wrote:Also regarding availability of HexVCA: Post Modular UK and Schneiders Buero should both have stock (they received shipments this week) and I believe Analogue Haven still has some as well.

How about Escapefromnoise? I really wanna get it from there, and have had a pre-order for the HexVCA (and some other Intellijel-stuff) for some time.

intellijel · Post by **intellijel** » Fri Apr 15, 2011 11:38 am

sparks wrote:
intellijel wrote:Also regarding availability of HexVCA: Post Modular UK and Schneiders Buero should both have stock (they received shipments this week) and I believe Analogue Haven still has some as well.
How about Escapefromnoise? I really wanna get it from there, and have had a pre-order for the HexVCA (and some other Intellijel-stuff) for some time.

Escapefromnoise get their stock from SchneidersBuero. Now that SB have stock (they were majorly delayed due to their involvement with Musikmesse) EscapefromNoise should be getting a shipment from them.

sparks · Post by **sparks** » Fri Apr 15, 2011 11:45 am

intellijel wrote:Escapefromnoise get their stock from SchneidersBuero. Now that SB have stock (they were majorly delayed due to their involvement with Musikmesse) EscapefromNoise should be getting a shipment from them.

Aha, I was aware of, but did not think about, that.
Makes sense. Thanks for the answer.

Really looking forward to the uScale as well.

haven · Post by **haven** » Fri Apr 15, 2011 1:12 pm

One of the big differences in sound between different VCAs I have tried is the way they react to audio rate modulation.

All the Doepfer VCAs I have tried sound much less detailed and blurry when modulated at audio rates compared to the HexVCA and Azimuth or Cwejman VCAs. Cwejman and Intellijel are using THAT VCA chips, where the Doepfer ones I tried are CEM. This is shown in the HexVCA demo video Danjel put on Vimeo. THAT VCAs also react to fast envelops more accurately in my experience.

So if you were interested in using a VCA for sound design (I love love love AM patches) or short click sounds like in modern techno I would recommend the Intellijel VCAs. Or of course Cwejman if you have the extra money.

Keep in mind I work for Intellijel and have not tried all VCAs available so I am slightly biased.

MOD WIGGLER

MOD WIGGLER

intellijel Hex VCA