hen's tooth cafe contestant, micmix dynaflanger

[Tompski]

What if someone on this thread boiled the main ingredients of this story down to an email that we could send out to a shortlist of suitable pedal builders around the globe and see if we can ignite someone's interest in building it? is the there not another bbd/chip that can be used instead?
What about the original designer/builder? He could have a come back like Mike Biegel from Mutron! Am I dreaming???

Although we all know we are after that sound that Frank got so we need someone to build two in one so it may need to stay as a rack or half rack.
Surely someone can build a modern interpretation which has the same functionallity?

[Redvers]

Hi guys, first post. Has anyone here played a Zoom GFX 707? It had an effect called time trip which was envelope controlled delay. But it had mix control, feedback and sensitivity. It did everything from warped tape sounds, delays that got longer and shorter according to picking dynamics, chorus, but most importantly it did the Dyna flanger sound.

It could do positive and negative too so its worth checking out because you could throw two of these in a rack, maybe use the other fx, comp, wah, delay etc and get a pretty close approximation of the Dynaflanger very cheaply.

[pinkjimiphoton]

we need to ressurrect this beast. SOMEONE has gotta have one. i'll be seeing dweezil next month, and if i can chat with him after the show again, i'll ask if he'd consider letting one of us see an actual unit, get gut shots/measurements etc.

i'll ply him with pedals and hope for the best. but i mean, shoot, if we could bring the ludwig back from the shades, and dino and phil could do the same with they synthi. what the hell, right?

[PMowdes]

we need to ressurrect this beast. SOMEONE has gotta have one. i'll be seeing dweezil next month, and if i can chat with him after the show again, i'll ask if he'd consider letting one of us see an actual unit, get gut shots/measurements etc.

i'll ply him with pedals and hope for the best. but i mean, shoot, if we could bring the ludwig back from the shades, and dino and phil could do the same with they synthi. what the hell, right?

Consider me interested.  I've downloaded the schematics.  perhaps i'll have a go at drawing something up, I've got a relatively clean slate at the moment

Could we use the SAD1024 mods that were put on the mutron flanger at all here??

[Scruffie]

The Mutron ran the SAD1024 in series configuration if I recall so was using the 3007 as intended.

Besides the point, it wont be too hard to adapt to an MN3007 but we need to know the clock frequencies. Given the heavy filtering at 25KHz it's a good chance the minimum is going to be 50KHz so we'll need to double that to 100KHz so just halve that 50pF clock cap, assuming a 20:1 sweep ratio the max is going to be 2MHz so it'll definitely need a 4049 buffer.

The current mirror output'll need flipping but apart from that...

Edit: Whoops, forgot the parallel multiplexing, 25-500kHz might be more likely in which case a 4049 shouldn't be necessary.

[digi2t]

Well, since my bro P-mow has jumped into this fray, I guess I'll take a dip too.

I have a whole bunch of these...



They are KA528БР2 (KA528BR2). Russian equivalents (supposedly) to the SAD1024, but with worse signal to noise figures than the 1024. Not really sure how that would impact the overall performance, but if someone can help me with the pin to pin translation, I would be ready to push this into service here.

Here is the datasheet (in Russian); https://www.promelec.ru/pdf/528br2.pdf

I think I have a VERY loose translation of an application note somewhere at home, but I'm on the road till Wednesday. In the meantime, here an app sheet; http://www.155la3.ru/datafiles/ka528br2.pdf

[Scruffie]

I've read they're more like MN3001 which is a very big distinction and would be far worse than an MN3007 in this application.

We'd need to know its insertion loss if any, it's gain vs. freq, it's clock pin capacitance, P or N channel, if the output voltage varies with frequency and if it needs gate biasing.

I can take some guesses from the graphs in those folders as to what's what and if they're right, while not bad in areas, it's not really the best suited for this job. Headroom looks more like a 320X series chip, gain vs. freq looks pretty good, don't see any gate biasing in the application, insertion loss is 5dB (which would be what makes it more like the MN3001 and is the real killer) and I think its saying it'll run from 20kHz - 1MHz so I assume the clock pin capacitance isn't too high. It would however, be perfect for a Tychobrahe Pedal Flanger clone...

[Kevin Mitchell]

While googling for DanaFlanger gutshots...
https://www.youtube.com/watch?v=VQ-UCvlRGlc

-KM

[Kevin Mitchell]

This would make a good winter-time project. I have both MN3204 and MN3004 BBDs that I could play with here. Perhaps I could grab a TDA1022 as well seeing how SB has a stock of them. Though it would be best to get a clone running with an SAD1024 first but getting my hands on one of those could be a nightmare.

There's a few rackmount units I would like to build and this one is high on the list.

-KM

[Scruffie]

This would make a good winter-time project. I have both MN3204 and MN3004 BBDs that I could play with here. Perhaps I could grab a TDA1022 as well seeing how SB has a stock of them. Though it would be best to get a clone running with an SAD1024 first but getting my hands on one of those could be a nightmare.

There's a few rackmount units I would like to build and this one is high on the list.

-KM

The MN3204 & TDA would be very poor choices, the MN3204 would require TTL logic for the clock or a total redesign and the TDA has awful insertion loss that you'd need to find somewhere to counteract and which is going to make noise a lot worse.

The MN3004... it's not perfect, again, insertion loss (although nowhere near as bad as the TDA) and poor gain vs. clock specs (the datasheet has it losing 1dB at a 10:1 ratio) but it might be acceptable, only you'll need two of course.

[Kevin Mitchell]

The MN3204 & TDA would be very poor choices, the MN3204 would require TTL logic for the clock or a total redesign and the TDA has awful insertion loss that you'd need to find somewhere to counteract and which is going to make noise a lot worse.

The MN3004... it's not perfect, again, insertion loss (although nowhere near as bad as the TDA) and poor gain vs. clock specs (the datasheet has it losing 1dB at a 10:1 ratio) but it might be acceptable, only you'll need two of course.

Thanks for the input, Scruffie!
I have 3 MN3004 BBDs in a Hammond XB-2 I'm likely going to scrap and retrofit. Figured it would be worth the experiment! But as I said - I'll try with the SAD1024 first and then go from there.

-KM

[pinkjimiphoton]

what about adapting it to use FPGA's? (Field Programmable Gate Arrays)
i was told you can use them to emulate most analog chips... and looking at the schematic for the SAD it doesn't look too complex, just a shit load of the same thing 1024 times

[petey twofinger]

sorry to zombie boost this but a man can dream

[wayne kirkwood]

I worked at MicMix and, along with Bill Hall, developed the prototype DynaFlanger. Bill left MicMix before the product came to market - it was my job to bring it into production. The schematics posted here and in the OP are from my file copies.

A couple of years ago I re-introduced another MicMix product, the XL-305 reverb, which is/was built by AudioScape. https://www.audio-scape.com/products/xl-305r The XL-305 was reborn here: https://micmixaudio.com/forum/php/viewtopic.php?f=6&t=213

I've always wanted to do an improved DynaFlanger or DynaPhasor - one of the experiments I ran back in the early 80's was to add an exponential converter between the control voltage stage and VCO clock. It tracked frequency and envelope in a much more musical way. I think Frank would have liked it. The DynaPhaser prototype used SSM2040 filters - today I'd use THAT VCAs. https://micmixaudio.com/forum/php/viewtopic.php?t=368

There's a tiled easier-to-follow version of the DynaFlanger schematic here: https://dynaflanger.com/forum/php/viewtopic.php?f=12&t=612

I sold my DynaFlanger back in the late 80's and the original work was done almost 45 years ago. There's no reason I see an MN-series couldn't be made to work to replace the SAD1024 particularly in a design that has two MN running in parallel with one fixed and the other providing delta-T to provide zero-crossover flanging.