OK, thanks
Pin 2 - 4.82
Pin 3 - 4.35
Pin 4 - 0.0
Pin 6 - 4.82
Pin 7 - 9.69
That's ok!
Now you have to trace your audio signal - with an oscilloscope.
Best way is feeding a continuous sinewave in the range of 300..3000Hz into you input. If you do not have a signal generator, use your PC and sound card output. "Audacity" may generate the signal. Output level should be several hundred mV(rms).
Is that signal at pin3?
Is it at pin6 as well with bigger amplitude?
If you can't provide an oscilloscope, ac-measurements with your DVM are an option.
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I will say that the resistance values are way too big for low noise performance...
I highly suggest you calculate and do a noise analysis of the circuit to see what is happening...
The Power supply is critical ....if your power supply is not clean, you will inject more noise into your circuit....
A BUFFER can affect the audio in many ways....
I look at a BUFFER a bit different.... because a BUFFER may sound different than when no buffer is used...
For example, the output of an instrument working into a High Z BUFFER will not produce the same frequency response as if plugged into int's original intended target load...for one, the loading affects the damping and Q as well as losses...
I try to make BUFFERS that sound transparent....as if they weren't there... I do this by making the input of the buffer having a similar input impedance of the original intended load so that the instrument output behaves more naturally...especially a guitar output...since I don't like ringing from poor damping, which may show up with a High Z traditional Buffer...
I highly suggest you calculate and do a noise analysis of the circuit to see what is happening...
The Power supply is critical ....if your power supply is not clean, you will inject more noise into your circuit....
A BUFFER can affect the audio in many ways....
I look at a BUFFER a bit different.... because a BUFFER may sound different than when no buffer is used...
For example, the output of an instrument working into a High Z BUFFER will not produce the same frequency response as if plugged into int's original intended target load...for one, the loading affects the damping and Q as well as losses...
I try to make BUFFERS that sound transparent....as if they weren't there... I do this by making the input of the buffer having a similar input impedance of the original intended load so that the instrument output behaves more naturally...especially a guitar output...since I don't like ringing from poor damping, which may show up with a High Z traditional Buffer...
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Hi everyone, my first post.
I just made it in a breadboard (only change is instead of the 2.2MOhms I put 1.8M resistors) and it works (connected to an ADI AD2000B onboard sound card, I have an X-Fi Xtreme Music but the line in sucks). But I don't like it: it sounds too fat. I made some (small changes 100nF to 22nF and 1MOhm to 3,3Mohm) but still sound just too fat: the "chunk" sounds just horrible (tested in Guitar Rig 5 and apart with a MT2 before this circuit, of course..). What can I change to solve that (I adjusted gain and volumen of everything)?
I also have in the breadboard this circuit MPF102 FET Preamplifier FAQs, Part 7: Other Preamplifier Circuits and the "chunk" sounds fine (with GR5 the MT2 and other distortion effects), the problem is that is a bit noisier and either too bright or having a high frequency "susceptibility"(?), or something else...
What I'm actually after is a circuit in I can switch Via SPDT or DPDT between cabsim and no eq (like this one) without having to readjust volume (so instead of 2 different circuits) that accept effect pedals before it and that have enough quality for home recording (low noise, no artifacts). The use would be sometimes recording wit Guitar Rig or other similar programs in which one needs no eq and other times with a stompbox or pedal before and recording with an audio editing program or something similar. Also have to be compatible with ordinary home or studio mixers. And not use Fets or US transistors as I can't easily reach them here, only common opamps, mosfets (BS170 and 2N7000 and some IRF) and european transistors (BC546 to 50, BC556 to 560)
I already experimented with some cabsims and preamps making hybrids but none worked fine.
Could this be what I'm after?: BOSS Speaker Simulator TM-3 (modified)[pict] - Symulatory paczek CabSim - guitar effect pedals gitarowe Guitar Pedals - schemes drawings schematics - schemes drawings schematics | GuitarElectric.eu
Everybody says that this one https://guitar-gear.ru/index.php?p=proj&id=59 sounds very good how could I modify it for my stuff? What about this one Multicab SIM..my own design cabinet simulator .. it works!! cool!
I did some simplers like https://dl.dropboxusercontent.com/u/11178619/Cab Simulation/simple_cabsim2 Resistors.png and https://dl.dropboxusercontent.com/u/11178619/Cab Simulation/TrueVAL/Two NPN CabSim.JPG , both of them sounds good specially the first one (the second I took all what's after the first bc549c and sounds exactly the same so I do not want to see this one again haha), Bulldog and Condor too many people said are not good and prefer all the others, except the TM3 which I have no idea how it may sound.
Sorry for the lenght and I hope someone could help me on this, I think is useful and interesting!!
Thank you!
I just made it in a breadboard (only change is instead of the 2.2MOhms I put 1.8M resistors) and it works (connected to an ADI AD2000B onboard sound card, I have an X-Fi Xtreme Music but the line in sucks). But I don't like it: it sounds too fat. I made some (small changes 100nF to 22nF and 1MOhm to 3,3Mohm) but still sound just too fat: the "chunk" sounds just horrible (tested in Guitar Rig 5 and apart with a MT2 before this circuit, of course..). What can I change to solve that (I adjusted gain and volumen of everything)?
I also have in the breadboard this circuit MPF102 FET Preamplifier FAQs, Part 7: Other Preamplifier Circuits and the "chunk" sounds fine (with GR5 the MT2 and other distortion effects), the problem is that is a bit noisier and either too bright or having a high frequency "susceptibility"(?), or something else...
What I'm actually after is a circuit in I can switch Via SPDT or DPDT between cabsim and no eq (like this one) without having to readjust volume (so instead of 2 different circuits) that accept effect pedals before it and that have enough quality for home recording (low noise, no artifacts). The use would be sometimes recording wit Guitar Rig or other similar programs in which one needs no eq and other times with a stompbox or pedal before and recording with an audio editing program or something similar. Also have to be compatible with ordinary home or studio mixers. And not use Fets or US transistors as I can't easily reach them here, only common opamps, mosfets (BS170 and 2N7000 and some IRF) and european transistors (BC546 to 50, BC556 to 560)
I already experimented with some cabsims and preamps making hybrids but none worked fine.
Could this be what I'm after?: BOSS Speaker Simulator TM-3 (modified)[pict] - Symulatory paczek CabSim - guitar effect pedals gitarowe Guitar Pedals - schemes drawings schematics - schemes drawings schematics | GuitarElectric.eu
Everybody says that this one https://guitar-gear.ru/index.php?p=proj&id=59 sounds very good how could I modify it for my stuff? What about this one Multicab SIM..my own design cabinet simulator .. it works!! cool!
I did some simplers like https://dl.dropboxusercontent.com/u/11178619/Cab Simulation/simple_cabsim2 Resistors.png and https://dl.dropboxusercontent.com/u/11178619/Cab Simulation/TrueVAL/Two NPN CabSim.JPG , both of them sounds good specially the first one (the second I took all what's after the first bc549c and sounds exactly the same so I do not want to see this one again haha), Bulldog and Condor too many people said are not good and prefer all the others, except the TM3 which I have no idea how it may sound.
Sorry for the lenght and I hope someone could help me on this, I think is useful and interesting!!
Thank you!
Try to further reduce the input cap, according to your taste.
Btw, most american parts are available in Europe as well.
Ops! Ignore my post before this one. I'll try it this in an hour! I'm in South America
sometimes there is...but most of the times there's not...I kept changing the input cap from the original 100nF to 22nF, 4.7nF, 3.3nF and 1.5nF where I finally heard some difference... but were still sounding bad, too rough on the lows, useless for metal music. Didn't change the output capacitor...will that make any difference?
But better... is there any other low noise "guitar to PC interface" circuit so I can test? Can't find any...
But better... is there any other low noise "guitar to PC interface" circuit so I can test? Can't find any...
My TL071 appears to be dead. It either came that way ( very unlikely ) or my lousy soldering technique killed it
I'll investigate a bit further though I don't hold out much hope. I need some proper test gear.
Like Fergutor I'm building this as an interface to amp modelling software rather than as a booster. But that's another story...
I'll investigate a bit further though I don't hold out much hope. I need some proper test gear.
Like Fergutor I'm building this as an interface to amp modelling software rather than as a booster. But that's another story...
Yes it can, but it will be dependent on the sound card's input impedance at that point. And the same thing for the input cap, it will have some dependance on the guitar plugged into it.
What I think you are looking for is low end roll-off, and the place to cut that boominess is at the 10 uF. Try a lower value of capacitance. This is a rudimentary EQ, and depends what you want the preamp to do , wide range for multi instruments, or specifically your style of guitar and music.
If you want to play with both you can put a switch and call it ''low cut''.
Cheers
Ok so I reduce the value of the output capacitor to 4.7uF and 1uF and barely changed. Then I reduced the other 10uF cap, the one to ground, to 4.7uF, 3.3uF, 1uF and 10nF, and that made a more noticeable change but still sounded bad. I removed it and that cutted most of the bass...still sounded bad (and now with little bass). Then I changed R1 to 150k and that seemed to make some improvement changed both R1 and R2 to 10k and sounded like before...
This "bad sounding" is like instead of playing a guitar I was playing a bass guitar slapping it, like a violent beat to the strings, not with distortion or clipping, just like I said and nothing like a guitar should sound.
So I think I tried everything, no? If so this circuit is not for me...
My guitar is an Epiphone Explorer GT with the original pickups
Neck pickup: 650R Alnico humbucker
Bridge Pickup: 700T Alnico humbucker
...Have any other circuit around to test?
This "bad sounding" is like instead of playing a guitar I was playing a bass guitar slapping it, like a violent beat to the strings, not with distortion or clipping, just like I said and nothing like a guitar should sound.
So I think I tried everything, no? If so this circuit is not for me...
My guitar is an Epiphone Explorer GT with the original pickups
Neck pickup: 650R Alnico humbucker
Bridge Pickup: 700T Alnico humbucker
...Have any other circuit around to test?
My TL071 appears to be dead. It either came that way ( very unlikely ) or my lousy soldering technique killed it
I'll investigate a bit further though I don't hold out much hope. I need some proper test gear.
Like Fergutor I'm building this as an interface to amp modelling software rather than as a booster. But that's another story...
"I killed" 3 TL071 doing the MXR Headphone Amp (2 on breadboard!), so those, the BC54x and BC3xx type transistors have to be most delicate components I encountered so far (again died even on breadboard without even fiddling with them).
Hey, tell me how it went with this d... circuit. See if you have the same effect that I had (I described it in my last post)...
As an interface from a guitar to a line input, I dont think any voltage amplification is needed, just a reasonably low impedance output. Transients are already up around 1 to 2v so no need to boist them.
Ive built a number of such circuits with just a single jfet source follower.
It works better than you think it might, using a 9v power source. But it can be further improved in a few ways i terns of biasing and power supply
Ive built a number of such circuits with just a single jfet source follower.
It works better than you think it might, using a 9v power source. But it can be further improved in a few ways i terns of biasing and power supply
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As an interface from a guitar to a line input, I dont think any voltage amplification is needed, just a reasonably low impedance output. Transients are already up around 1 to 2v so no need to boist them.
Ive built a number of such circuits with just a single jfet source follower.
It works better than you think it might, using a 9v power source. But it can be further improved in a few ways i terns of biasing and power supply
Great. Just now I was experimenting with one modified circuit that maybe doesn't amplify anything, and as it's part of a cab sim, without the sim part, would be perfect for me...if I could just fix that strange bass that's haunting me here too (opamps again)! GRRRrrr...!!
Now about your circuit...I can't get FETs here (only in great quantities, and very expensive), what about with BS170? Like this one Guitar pre amp based FET - Amplifier Circuit which is very similar to yours. It says that that the input impedance is about 500ohms, so that can be changed, but doesn't talk about the output impedance. So what are your thoughts on this, how could be modified?
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