I have to say I really like this thing - thick, meaty bass.

bought a 2nd hand model d a while ago - same thing. turned out, somebody used it in an eurorack an didn't reconnect the ribbon from the main board to the outputs after reassambling it. or maybe the ribbon is just lose?

I was long looking for Pro One and almost got one couple of time, couldn't be happier with this clone

Interesting, i'll have a look inside.

If you really want an authentic SCI PRO-ONE experience with the Behringer, you need to fit your PRO-1 with a *broken* keyboard.

-former owner of three Pro-Ones.

your machine your choice but, i would say don't send rando sysex files to enter dfu mode - very easy to get stuck in there depending on the programmer inside and then you may end up needing access to a st link or similar and hoping the same hive mind that got you in the crapper can actually help you get back out, that or making a warranty claim, the latter will throw up the reason the machine is stuck

if you think you want an older FW request it

Just for the record, Behringer uses the term DFU mode for their bootloader, which is different from any built-in DFU mode that the microcontroller might have.

An owner of two original Pro Ones here - I had the keyboards swapped for modern replacements a few years ago and they finally became the synths they should always have been. The difference is phenomenal.

Same here - they are a joy to play now.

Hi.
Just got a PRO 1 and have a question about the filter cutoff range. I am getting no change in filter response from the 2 o'clock position to full open.... is this normal? From zero to the 2 O'clock position i get the nice filter sweep i am expecting.. seems like upper 1/3 of the knob motion is just full open filter sound.

I also thought it was weird. I ended up reading the original service manual for the Pro-One.
At a setting of ~6.5 the cut-off frequency goes ultra-sonic.
No idea why they would do it like that.
I wish the low end would go lower - have the cut-off go below 0. You can send a negative DC signal to the cutoff CV if you want to create a low kick.

Yes. the filter does not get low enough for the deep low kicks... dont use CV to much.. how would some one send a Negative DC anyways.. what equipment would be needed...

A eurorack module like the Intellijel Quadratt or Triplatt could be used. Just plug one of the outputs into the Pro-1 filter cutoff CV, set the Quadratt/Triplatt channel to -/+ and turn the dial to the left to taste. When the Quadratt/Triplatt are used without an input, they just output a voltage based on the dial position. Super handy modules to have, given all the other things they can do (mixer, scaling, offset).

There’s likely ways to do it with other semi-modular synths as well, depending on what you have handy. I’m not sure if it can be done with Pro-1 self patching.

I have a Moog Grandma. The output from the attenuator can be used for this. If nothing is plugged into the input of the attenuator, the output works like a DC signal.

You can also try with a negative envelope to get the cutoff below 0.

I haven't found a way to do it with just the PRO-1.

A couple of oversights??

* Maybe you guys can sanity check my observations, but I noticed you can't switch Arpeggiator Modes while the Arp is running. That was an interesting feature of the old one to be able to switch from Up to Up/Down (or Down if that's how your Pro-One was hardware configured).

* Also it does not recognize the MIDI Sustain (hold) pedal. I checked the MIDI that the controller was putting out and it was OK as far as I could tell. This could be useful for live in place of the panel switch. There are a couple of ways to implement that, but I didn't notice any recognition at all.

Hi guys,
former owner of a SCI Pro-One back in the '80s and now fresh owner of B. Pro-1. I admit it touches the general flavor and a rapid tweak of the control panel worked as a sonic time machine, with some quirks. My unit exhibited inconsistent Attack-Decay-Release max. times:
Filter Envelope
Attack time max. 3.5 seconds, Decay time max. 13 seconds, Release max. 28 seconds

Amplifier Envelope
Attack time max. 6.5 seconds, Release time max. 18 seconds, Release time max. 32 seconds

I filed a ticket at MusicTribe Support and soon was asked to send them a short video showing the issue, I sent them a detailed test of the A-D-R times arranging a simple patch with the envelope under test routed to Oscillator Frequency. I got a reply after 2 weeks telling me that the development team after seeing my video didn't find any fault and that my Pro-1 -from their point of view- is working as designed.
I told them what I think of such a short-sighted "development team" that don't know how a synth should properly work.

I sent my unit back for replacement and hope to get a better working one, by the way I would ask if anyone is experiencing such inconsistent envelopes.

Obviously I updated the firmware.

thanks in advance
Max

Since the envelopes are digital on the Behringer Pro-1 I imagine they will all be about the same.

Be sure to update the firmware?

He said he did, but it might be nice to know which version of firmware he is using. There are several versions out in the wild.

Version 1.3.1.
SynthTribe found the latest release available and prompted to update the Pro-1. No choice of different firmwares.
After recognizing the ADSR issue I did a reset, checked for improvements then performed the firmware update again. No change.

For the record, I asked MusicTribe support if there was a chance to fix the ADSR behavior with a specific firmware. As I said, they even didn't recognize envelopes are broken. Probably they never see a proper working synth nor stumbled on the Sequential Circuits' Pro-One owners manual. Or they just copied a broken Pro-One and that's it... who knows.

If B are trying to copy the OG specs with their envelopes, A, D and R should be around 1sec when set to "6" and R should be at least 15 secs when set to max (and I'm guessing the same is true of A, D max)

In my experience A,D,R are more like 1.5-2.5 on OGs when set to "6" and A,D around 15-30s on max, R times go up to 30-60s, although sometimes the max times for them all go higher. There is variability between filter and amp envelope times. These are with ageing components.

Yours seem quite typical for an OG apart from the max attack times seem short, and maybe the max filter decay a little low. When you get a replacement you could check the times at "6" to see if they are the right sort of length there.

my 2 cents:
If you're unhappy with it send it back and move on - I did that with their MS-1(01) which mostly doesn't even sound like the original. Got their Pro-1 as well, but that difference in the envelopes luckily doesn't bother me.

Before SynthTribe.exe, there were other loaders and these used typical .SYX firmware files. So there are many other firmware versions out there. SynthTribe.exe makes the firmware distribution hidden and very controlled, so without major detective work you are stuck with the current version. The TD-3 users have made some headway though.

Unfortunately I sold my Pro-One about 1986 and at that time I didn't use to meseaure ADSR times against the manual specs, it simply worked beautifully and never disappointed me. OG manual declares equal time range of "from 2 ms to more than 6 s" for both envelopes, from memory I can't disagree.

What's definitely wrong with my unit are the uneven full scale values of each envelope stage, it's in no way acceptable be it pure analogue or digital design. (IMO) ADSR stages must all behave the same way, otherwise it's a designer (or circuit) fault. Once full scale values are regular and even then we can talk how the potentiometers (or encoders) position influences in-between values; but this relates only to the inner potentiometers law (linear, logarithmic..) and the connected discrete network in the analogue domain or how the encoder rotation is mapped in the digital domain.

Sorry for being wordy.

Max

I sent it back. If the next unit will show the same issue then I'll have to chose between a further replacement or a refund. At the moment I am prone to think of quality check fault.

Apart from ADSR long times (r...), fiddling with the panel controls of the Pro-1 was a pleasure in that it clearly inherited the timbric personality of the OG and I easily reproduced plenty of sound patches I loved. So there are not only complaints.

No worries. Just saying that OGs I've owned/played also have different max times on different stages and on the two different envelopes...

... and would still be considered within spec according to the OG service manual, which only refers to position 6 (~1sec) and max release times being at least 15 seconds.

Will be good to know if your numbers are right for all Pro 1's (with latest firmware) i.e. B's model is like that - or whether yours was bust somehow.

Thanks, I will take a look.

Still love this Pro-1 Clone, the reason why it doesn't play notes below C1 when triggered via MIDI/USB has never been answered, or has it?

I still hope there'll be someday a firmware update, that makes the built-in Midi-to-CV converter go 1-2 oktaves lower.

Totally agree, discrete components degrade over time, especially true for capacitors... my Korg MS-20 (1983) exhibits a degraded keyboard sample/hold capacitor, sustained notes over 10 seconds start to slowly decay in pitch. It can be fixed but I like it like that.

This is my point, too. Hence my post here. Pro-1 owners, let's know how good are your ADSRs

I fear there is some hardware limitation that doesn't allow such an octave extension from MIDI. But you can easily step over it and get plenty of sub-bass: set Oscillator B in Lo-Freq mode, re-tune if necessary and be done. Maybe lower Oscillator A volume for overtones, or just sync it to Osc. B and play with harmonic content at taste. Cutoff and Resonance as you like.