Questions tagged [synthesizer]
The synthesizer tag has no usage guidance.
107
questions
1
vote
1
answer
19
views
Help IDing a high-power IC - OODOW 836 T57
I'm fault finding for a Korg M50 Synthesizer.
Symptoms: on every boot a message appears saying the device is updating the left/right control panel firmware, after which it requests a re-boot. ...
- 309
0
votes
0
answers
37
views
Info about this older transformer from my Kimball organ
I have been harvesting parts from my dying kimball "Swinger 300" and I finally got around to disassembling the power supply. It had what I assumed to be a transformer attached, as the only ...
- 1
0
votes
0
answers
83
views
How to synthetize a 10 kHz signal from 1 Hz analogically
I would like to synthesize a 1 Hz signal to a 10 kHz one without using MCU or related DPLLs.
Anyone has a schematic example? I found this reference schematic on Art of Electronics.
Would that suit (...
- 79
1
vote
1
answer
94
views
How to properly connect oscillator circuit to amplifier?
edit v2:
Schematics:
The ic on the left is a 40106, and the thing inside is a Schmitt trigger with inverting output.
In 'edit v1' below you can see a wiring diagram.
edit v1:
Rough schematics and ...
- 27
3
votes
1
answer
65
views
How to debug unexpected behavior on voltage-controlled oscillator PCBA?
I designed a circuit for a voltage-controlled oscillator (VCO) for use in a synth and had it fabricated and assembled as a PCBA. I got three assemblies back and while two behave exactly to spec (and ...
- 358
0
votes
1
answer
44
views
Replacing a linear softpot (ribbon sensor) with a regular potentiometer
I'm a beginner with electronics. I'm trying to replace a softpot on a cheap synthesizer with a regular potentiometer. As far as I can tell this component (pictured below) behaves just like a 10K pot; ...
- 163
0
votes
0
answers
95
views
Modern temperature compensation of 1 V/oct VCOs
With Akaneohm Tempco resistors going out of production, I have been searching for alternative ways to reliably build a VCO that does not drift with temperature. I have been searching around, but I can ...
- 11
0
votes
0
answers
25
views
How to get freq stability with constant offset for PLL synthesizer?
I used ADF5356 PLL synthesizer. And i use reference oscillator freq is 10MHz with initially offset 0.1ppm and stability is 10 ppb. I need to output freq is 3750 MHz.
Expected output result:
10MHz × 0....
2
votes
1
answer
95
views
Verilog netlist synthesis using assign vs always [duplicate]
If you have some sort of Verilog implementation like:
...
- 207
0
votes
0
answers
34
views
Conditioning inputs and outputs when using virtual ground
I am using a 120 VAC to 30 VDC single-sided supply to power a synthesizer that requires double ended power supplies, +/-15 V.
I am using a TLE2426 rail splitter to create a virtual ground, then ...
1
vote
1
answer
76
views
Diode voltage drop characteristics in an envelope generator design for audio synthesis
I have no actual EE knowledge, I have just been fiddling around with audio circuits for a while.
I built an attack-decay envelope generator for audio synthesis purposes following a design by Ray ...
- 13
2
votes
1
answer
123
views
Reliability issue of HMC833 PLL
We are using an HMC833LP6GE PLL in our design for generating 122.88 MHz from a reference of 100 MHz.
We are feeding a reference signal of >5 dBm. What we are observing is that out of 10 times, if ...
- 197
2
votes
2
answers
125
views
DAC to quad op-amp for Arduino FM synthesizer
I'm working on a little Arduino digital synthesizer powered by an old Yamaha sound chip (YM2151).
I have a fairly good understanding of how to connect the YM2151 to the Arduino and the YM2151 to the ...
- 21
1
vote
1
answer
268
views
How to set LMX2820 MUXOUT for SPI readback
I am controlling an LMX2820 synthesizer over SPI. I want to perform SPI register reads and need to use the chip's MUXOUT signal as SDO pin as SPI MISO.
I expect to have to set MUXOUT_SEL to assign ...
- 13
3
votes
1
answer
89
views
Is there any way to tell the current used by a particular SD Card?
I need to replace an SD card that came with a piece of electronic equipment (specifically, a sequencer for a Eurorack modular synthesizer). The SD card that came with the module is 1GB, and is a no-...
- 135
1
vote
0
answers
52
views
LMX2820 readback operation [duplicate]
How can a readback operation be done on LMX2820?
I've looked through over it's datasheet, register map and AN documents and there is no information about that. In LMX2594 read and write operations are ...
- 131
0
votes
0
answers
53
views
Analog step sequencer schematic help
I'm currently working on an analog step sequencer for a synthesizer I'm making. It has a split rail 24 V supply (so +12V, GND, -12V) and follows the Kosmo specification. The features I want are:
8 ...
- 43
0
votes
1
answer
39
views
How should I go about overriding or switching between an internal control voltage source when an external source gets connected?
For example, I'm using a potentiometer to modulate an internally generated +5v audio signal, and I'm sending the output signal down to the next part of my circuit. If I were to add an external input ...
- 120
3
votes
1
answer
887
views
Headphone output - what is the function of these resistors going to ground between the decoupling capacitors and headphones
The Korg Monotron Duo synth uses the TPA6111A2 headphone amp. The circuit they use is largely the same as the one from the datasheet - except for R78, the 470ohm resistor going to ground right after ...
- 141
3
votes
1
answer
265
views
Analog synthesizer- Add second VCO
I am working on reviving an old synth design (Transcendent 2000), but I would like to add a second oscillator. I was thinking of doubling the circuit highlighted below, and sharing the pitch control (...
0
votes
1
answer
219
views
~3400 ppm/C resistor replacement/substitute?
I am working on reviving an old synth design (Transcendent 2000 for those interested) and the VCO and VCF both rely on high ppm/C resistors to compensate for temperature changes. I can include the ...
1
vote
1
answer
181
views
Purpose of PNP transistors connected base to base in 1V/Octave synthesizer keyboard circuit
The circuit below (found here) is designed to be used in a 1V/octave keyboard used to control a synthesizer. When the potentiometer is adjusted properly, pressing the buttons produces output voltages ...
- 11
3
votes
1
answer
167
views
How can this 74 series Inverter circuit be analyzed?
I'm trying to analyze the keymech scanning / sampling circuit in the WASP synthesizer
So far I understand that the keymech is sampled one key at a time by the 74 series logic driven by the dual ...
- 988
0
votes
0
answers
80
views
How to stabilize this CV triggered toggle (555 timer latching switch) when fed with two gates?
I created the prototype for a modular synthesizer module. The project goal is an AND gate that is fed with two control voltage inputs (A and B with an Vpp around 5V). There will be two outputs: the ...
2
votes
3
answers
86
views
How do different octaves sound different in the presence of a low-pass filter in a synthesizer?
Per my understanding, when playing a certain pitch, say 440 Hz (middle C), the VCOs will produce their corresponding waveforms (say sawtooth) at that frequency. Because of the characteristics of the ...
- 141
0
votes
3
answers
1k
views
Understanding sawtooth wave harmonics
I've been playing synthesizers for a while and I'm trying to understand their math and electronics better.
The sawtooth is one of the three common waveforms on most subtractive synths. The waves are ...
- 141
0
votes
2
answers
84
views
Could an analog synthesiser be made to run on USB power 2.5W?
5V USB is now standard and very convenient.
But I see a lot of synths and audio projects working with higher voltages ... from 9V to 12V to 22V etc.
Are there physics reasons for this? In that ...
- 121
0
votes
1
answer
94
views
Custom breadboard manufacturers [closed]
I'm not sure if this is the right StackExchange for this, but I'm interested in whether it's possible to get some custom breadboards made. That is some solderless prototyping breadboards with a couple ...
- 121
0
votes
2
answers
85
views
Help identifying circuitry diagram
Now first and foremost, I know absolutely nothing about circuitry - joined an computer science chatroom and they couldn't help, I have cross referenced the symbols to the internet to try and ...
- 1
-1
votes
2
answers
98
views
Identifying missing component from vintage synthesizer [closed]
I acquired a Hillwood C-1A synthesizer with a burnt circuit board with 3 empty holes where a part needs to go. I'd like to repair the board but I don't know what component to look for... Help?
The ...
- 121
3
votes
2
answers
185
views
A triple voltage supply from a dual supply
I have build a dual power supply for an analog synth (see image below).
The input source is a 12 VAC - 1.7A adapter. It is based on the Wall Wart power supply from Music from Outer Space.
Now I would ...
- 133
0
votes
1
answer
512
views
Difference between a frequency synthesizer and a frequency mixer
I have tried looking a couple different places but cannot find a concise explanation on the difference between a frequency synthesizer and a frequency mixer. My goal is to take a signal at 915 MHz and ...
0
votes
0
answers
73
views
Connect multiple bipolar PSUs to one torroidal transformer with center tapped secondary winding
I'm currently starting my ventures into building a modular synthesizer in eurorack format and am currently using a single power supply like this with a 12V AC wall wart:
Source:
http://...
- 101
0
votes
1
answer
113
views
Can I add a Sense connection to this power supply?
I have a synthesizer (Yamaha CS-50) and the power supply is broken. I don't know why but it always blows the fuse. I tried everything, changing components, testing the transformer, etc. The fault is ...
1
vote
1
answer
135
views
What is the "input" being fed into a Delta-Sigma Modulator in a Fractional-N PLL? Are bits needed for a specific resolution at the input or output?
I'm doing some reading into Fractional-N PLL design and I have a bit of conceptual confusion regarding a delta-sigma modulator used to toggle the modulus of a divider. If you're trying for a certain ...
- 51
1
vote
4
answers
139
views
Is an MPU capable of equal quality digital synthesis as a dedicated DSP chip? [closed]
Is there any factor which would cause a modern microprocessor ( such as an ARM Cortex A/M ) to be inferior at performing digital synthesis compared with a dedicated DSP chip of comparable speed?
At a ...
- 213
3
votes
0
answers
157
views
Sawtooth VCO DC offset issues
[Apologies in advance for possible misuse of terminology. I don't have any formal education in EE and am mostly self taught, so I may be lacking in some fundamentals.]
I am trying to design a discrete ...
- 31
1
vote
4
answers
3k
views
Audio output voltage range
I'm working on a synthesizer project and I'm confused on what the final audio output voltage should be. The idea is that I would send the audio to a speaker or headphone amplifier, so I don't have to ...
0
votes
1
answer
100
views
Why 90VAC from a synth's chasis that uses 12VDC PSU?
I have Korg's Wavestate synth. https://www.korg.com/us/products/synthesizers/wavestate/
It uses 12VDC PSU with two prongs, hence it has no ground pin. My power outlet is 220VAC. When I connect the ...
- 101
1
vote
2
answers
448
views
How will wire wound resistors affect the synth's sound?
I am soldering up Music from Outer Space: Noise Toaster synthesizer. The guy who designed it said that carbon resistors should be used ("The resistors should be carbon composition or carbon film&...
- 319
2
votes
3
answers
141
views
FET Written Inside Comparator/Op-Amp Symbol
I'm in the process of importing a bunch of old schematics from a 70's era synthesizer into KiCAD. In the process I've come across a symbol that I can't make sense of. It looks like this:
Does anyone ...
- 149
0
votes
1
answer
175
views
Power Line Decoupling in Eurorack
Can some please suggest if I am doing this right ?
The intended circuit is to used with opamp (TL072)
Have I understood the decoupling right ?
- 9
0
votes
0
answers
469
views
Using an Audio Signal for a Control Voltage for an Analog Synthesizer
I have a Moog Sub 37 Analog Synthesizer and a Korg SV-1 keyboard. Can I take the audio out of either the line outs or headphone out of the Korg and plug it into the volume or filter Control Voltage (...
- 105
1
vote
1
answer
910
views
Trying to make fuzz factory with CV inputs
I'm trying to construct some kind of fuzz factory modular from regular fuzz factory pedal.
Circuit of the original pedal is pretty easy, but I've tried to add some VCAs based on LM13700. Honestly, I'...
- 11
22
votes
6
answers
6k
views
Where do overtones in a 555 generated square wave come from?
I have built a 555 oscillator and connected it to a speaker.
Using an oscilloscope I adjusted the 555 to generate a 2.5kHz square wave.
I then held a microphone up to the speaker and fed the input ...
- 593
1
vote
1
answer
851
views
Analog exponential convert for MFOS VCO
I'm trying to understand the exponential converter in the MFOS VCO. Here is a link to the complete MFOS Noise Box synth schematic.
http://musicfromouterspace.com/analogsynth_new/NOISETOASTER/...
- 113
3
votes
2
answers
2k
views
Grounding Vcc and Vee?
I recently started electronics as my hobby. I'm working on this v/oct modular synth and in the schematic that I was working on, it did not make sence to me when all the Vcc and Vee are connected to ...
- 33
53
votes
5
answers
7k
views
Why does music synthesizer built from chain of astable multivibrator circuits get "out-of-tune" after a few hours?
I built a prototype keyboard/sound synthesizer using a chain of 13 astable multivibrator circuits whose outputs are connected to an audio amplifier chip (LM386) and speaker, all powered off a 9V DC ...
- 616
4
votes
1
answer
273
views
How can I get this circuit to "make noise"
I designed this noise generator circuit that uses a 1N514 Schottky diode with a VDB transistor amplifier(note: the upper VDB resistor is actually 15kOhm). Looking at the oscilloscope trace it seems to ...
- 724
0
votes
1
answer
85
views
Measuring Frequency Synthesizer specifications
I need to measure all the electrical specifications of the Frequency Synthesizer KSN-2346A+ from Mini Circuits that appears in this datasheet: https://www.minicircuits.com/pdfs/KSN-2346A+.pdf
but the ...
- 101