EHX - Riddle QBalls VCF

uncleboko · Post by **uncleboko** » 25 Oct 2011, 14:56

Any clues as to whether an OTA or opamp VCF is used?

uncleboko · Post by **uncleboko** » 26 Oct 2011, 06:56

And any guesses as to how tthe envelope generator is made up - it does sound very very good, and the slow sweep sounds as smooth as the Space Drum decay

uncleboko · Post by **uncleboko** » 28 Oct 2011, 06:49

Maybe something will surface eventually.

uncleboko · Post by **uncleboko** » 29 Oct 2011, 13:02

A youtube to circuit diagram function might be useful

uncleboko · Post by **uncleboko** » 09 Nov 2011, 15:21

A blank!

uncleboko · Post by **uncleboko** » 10 Nov 2011, 10:47

I'm wondering if they use a new in house IC for the VCF or whether a stash of CA3094s has been uncovered

uncleboko · Post by **uncleboko** » 11 Nov 2011, 12:57

uncleboko wrote:I'm wondering if they use a new in house IC for the VCF or whether a stash of CA3094s has been uncovered

R.G. · Post by **R.G.** » 12 Nov 2011, 21:40

The LM13600, LM13700, CA3280, and NE5517 are all closely equivalent in function to two CA3094s in a single DIP. There are differences in the Iabc input and the pre-distortion diodes as well as lower overall noise. Takes a bit of circuit adaptation, but not much.

uncleboko · Post by **uncleboko** » 15 Nov 2011, 15:04

R.G. wrote:The LM13600, LM13700, CA3280, and NE5517 are all closely equivalent in function to two CA3094s in a single DIP. There are differences in the Iabc input and the pre-distortion diodes as well as lower overall noise. Takes a bit of circuit adaptation, but not much.

This really is a riddle

earthtonesaudio · Post by **earthtonesaudio** » 15 Nov 2011, 16:00

Is there some reason to assume this is an analog pedal?

uncleboko · Post by **uncleboko** » 15 Nov 2011, 16:31

Because it sounds analog.

Scruffie · Post by **Scruffie** » 15 Nov 2011, 16:40

Quick Specs
80 Hz to 5 kHz frequency response tailored for guitar
Optional expression pedal control
Fully-analog circuit
Switch selectable analog distortion designed for guitar
Start and Stop sweep control
Low Pass, Band Pass, High Pass filter select
Start and Stop for filter sweep and Q control
Separate Dry and Effect outputs
9.6VDC 200mA power supply included

So yeah, it is analog.

LM13700 Based Envelope Filter I guess, they seem to use them alot now... no clue about the detection.

uncleboko · Post by **uncleboko** » 15 Nov 2011, 18:34

How are they doing the start & stop frequency envelope generator I wonder?

earthtonesaudio · Post by **earthtonesaudio** » 16 Nov 2011, 00:45

Scruffie wrote: So yeah, it is analog.

LM13700 Based Envelope Filter I guess, they seem to use them alot now... no clue about the detection.

Aha! I didn't scroll down enough on the EHX page, obviously.

Scruffie · Post by **Scruffie** » 16 Nov 2011, 00:51

earthtonesaudio wrote:
Scruffie wrote: So yeah, it is analog.

LM13700 Based Envelope Filter I guess, they seem to use them alot now... no clue about the detection.
Aha! I didn't scroll down enough on the EHX page, obviously.

Haha, I assumed it was digital myself, I just happened to catch that in the specs.

Easily done.

Post by **Ice-9** » 16 Nov 2011, 11:23

Could be a clue in this picture.

uncleboko · Post by **uncleboko** » 16 Nov 2011, 11:27

Am I seeing + and - 9v at the top?

Post by **Ice-9** » 16 Nov 2011, 12:24

uncleboko wrote:Am I seeing + and - 9v at the top?

No it looks more like 9v centre negative logo to me.

uncleboko · Post by **uncleboko** » 08 Sep 2016, 16:14

Amazing that no circuit has surfaced after all this time!

Post by **Ice-9** » 09 Sep 2016, 21:40

uncleboko wrote:Amazing that no circuit has surfaced after all this time!

Did you not see my post above where I circled in black a clue.