SkyWriter wrote: ↑

Tue Dec 22, 2020 2:03 pm

That's a beauty Rob!

How many HP ?

38HP, high grade pots and knobs, with production units at £250, the panel is black adonised rather than the Behringer printed ali.

Picture of the AMSynths 984 Quad Mixer - sounds fantastic - limited run goes into production next month

Hi, as part of my 2500 project I designed and started building a prototype 1038 using CEM3310's and 8 sets of trimmers selected by a rotary switch with 7 segment LED display. Pretty basic, as I wanted to imagine what ARP would have done. The ideas didn't make it into a Behringer 2500 project which w...

Hi, the AMSynths Moog modules are moving into production with product profiles on the web store this weekend and first shipments before Xmas. The PPG 303, 984, 905, 928 modules are on schedule. I may also release the DIY kits like 993, 904C, true CP3A. There will be a PPG 313 Sequential Switch, as i...

Hi, I have been modifying the Behringer CP3A-M to make both a true CP3 and a true CP3A. I will also try and clarify the designs. The Behringer module is an accurate clone of the CP3 with matched transistors and NO op amp. Great sound but its not a CP3A. The SOIC chip on the PCB is a 337 voltage regu...

The Behringer CP3A-M is actually a CP3 module, all transistor design from the IIIP. It will slew any signal below -6v, also makes for lovely distortion. Great for audio but not so good for CVs. The CP3 has a high cut filter which I have added to the Behringer with a toggle switch. To get a true CP3A...

I couldn’t say much in August due to NDA, but very pleased to see the 2500 modules getting to customers. The basic modules are released first and then then the more complex modules. The 1005 is a very flexible module for creating ring mod sounds and both filters have a very clear quality. The Env ge...

Hi The 993 connects to 902, 911, 911A Daughter PCBs and the 904C connects to a 904A Daughter PCB which is also used with the 904B. That part was easy as none of the jack sockets are normalised. The 993 inputs are wired to a 994 Multi. Next step is to pre patch the CP3A-O, 921A and 921B. This probabl...

The AMSynths AM904A Daughter board replaces the Behringer filter caps with larger value polypropylene,matched caps, to recreate the Moog IIIP 1967 low pass filter. The filter resonance has improved, with resonance down to 40Hz and a 3rd harmonic in self oscillation, low end response has also improve...

The AMSynths 993 module is up and running, with LEDs in the 911’s, no patch cables here...904C and 984 next

Hi, The stock 914 does sound very good and the SMD caps in the upper frequencies are fine, not harsh. The next level up is matched polypro and polystyrene caps, maybe with OPA4134’s. To do polystyrene caps in the HF bands really means a new PCB and some careful meaurement of the SMD values, although...

Hi, I have modified my 904B with matched 680nF polypropylene capacitors in the low range, and a pair of 180nF + 220nF polypropylene capacitors in parallel for the high range. Its a tight fit to get all the caps in, and the 180nF are mounted on the rear of the PCB. I like the sound.  My 904A has new ...

I have fitted the Alpha C50K to the 923 and they are an improvement, I also found some nice 14mm diameter knobs on Mouser. I have Bourns 1MA and 5KB on order and will test at the weekend on 911, 911A and 921B. The original Moog 921B schematic (not the 921) shows an unknown resistor R8 in parallel to...

The tempco is close enough to the 3046 to not be concerned about thermal drift. The 3046 is not heated and this is all smd in a small pcb. Adding a thermal paste might help but I see no evidence to do this. It tracks fine. Sorry Rob. The data shared here doesn't back what you wrote. If it were fine...

The tempco is close enough to the 3046 to not be concerned about thermal drift. The 3046 is not heated and this is all smd in a small pcb. Adding a thermal paste might help but I see no evidence to do this. It tracks fine. Its more of an issue if the wrong tempco was used or no tempco in the 112. A ...

Hi, the 923 does have reverse log pots, but Moog used steeper tapers and larger diameter pots back in the 1960’s. Behringer couldnt do a custom pot, unfortunately. Putting a resistor in series may create the right resolution at near max settings. I will try this

A quick update on my B55 mods and additional modules; 993 Trigger And Envelope Controller - prototype is being tested and the internal patching to the 911’s, 911A, 902’s looks possible without removing any jack sockets from the Behringer modules as they are not normalised. Pictures soon, my panel ma...

yep! Edited- thanks..

Hi, If you are building up a System 55 or IIIP using the B55 modules you might notice some missing modules; the 993, 904C and 928. At AMSynths I am making these for my Klaus Schulze IIIP replica, and the test panel for the 993 Envelope Controller is attached. If there is enough interest, I can make ...

Hi, One of the objectives of the Behringer collaboration is to bring an amazing set of euro rack modules, at large production volumes. Something that AMSynths could not do alone. We are a few weeks away from launch and we hope our customers will no longer be frustrated in the web store being out of ...

Hi Very exciting news as this brings an Audity replica closer to being made, especially as I have the schematics! The VCO’s are discrete but the LFO is 2030, the LP and HP are 2040. The resonant filter can be done with the 2164 as can the VCA’s. The envelope generator will have to be a CEM3310 or di...

eBay or UTsource
I can send them to you for free if it’s a small order
Drop me an email at sales@amsynths.co.uk

I must get my 702 working

10x 8109 JP8 filters will be shipping in 10 days, drop me an email at sales@amsynths.co.uk to preorder. The 8328 filter module is in stock now, for anyone wanting a CEM3328 low pass filter.

Very cool using the 3310 as a basis. How did you use the modulation input to vary the timing? I was aiming to get the replica into a 16 pin footprint...

Hi, I have started researching the IR3R01 envelope chip in more detail, and there is a post on my website to record progress to a working replica here: https://amsynths.co.uk/2019/05/09/roland-ir3r01-clone/ . If anyone has ideas or real world measurements please comment on the post or here. My initi...