First off, I am a complete newbie to electronics as well as audio engineering so please keep that in mind.
The first circuit is from: https://tataylino.com/guitar-preamplifier-circuit/. This is the guitar preamplifier.
The second circuit is from: https://www.ti.com/product/LM1875
1. Here is the preamplifier:
2. Here is the amplifier:
I would also like to know a few things. If they are able to be combined, what would power them? I was planning on powering the preamplifier circuit with a
The first circuit is from: https://tataylino.com/guitar-preamplifier-circuit/. This is the guitar preamplifier.
The second circuit is from: https://www.ti.com/product/LM1875
1. Here is the preamplifier:
2. Here is the amplifier:
I would also like to know a few things. If they are able to be combined, what would power them? I was planning on powering the preamplifier circuit with a
9V DC Wall Power Adapter, but I have no idea how, once combined, to power the entire system. Any and all help would be greatly appreciated.
Lm1875 needs 16 V supply minimum (single supply, and it won't have much power in this case). Also, you would need to use fig2 in the data sheet for a single supply.
TL072, if i remember correctly, allows max 30 V total supply voltage.
So you would use a single supply between 16 and 30 V DC.
Or a dual supply with 8+8 V to 15+15 V DC.
Or you include regulator(s) for the preamp to stay within allowed voltage.
TL072, if i remember correctly, allows max 30 V total supply voltage.
So you would use a single supply between 16 and 30 V DC.
Or a dual supply with 8+8 V to 15+15 V DC.
Or you include regulator(s) for the preamp to stay within allowed voltage.
Why do you want to combine those two? To make a practice amp? A gigging amp?
Reason I ask is the preamp looks maybe okay for guitar. Might put a switch in series with the distortion LED diodes, though.
The solid state power amp circuit may not be so good for guitar as such amps can sound pretty bad if driven to clipping (like guitar amps sometimes are).
Also, the choice of speaker can make a big difference in sound for guitar amps.
Reason I ask is the preamp looks maybe okay for guitar. Might put a switch in series with the distortion LED diodes, though.
The solid state power amp circuit may not be so good for guitar as such amps can sound pretty bad if driven to clipping (like guitar amps sometimes are).
Also, the choice of speaker can make a big difference in sound for guitar amps.
@askDIY Its not so welcome to post 2 very closely related threads. Sorry Im not great with electronics, but buy a 1 to 5 watt tube poweramplifier kit and combine that with your preamp and an efficient guitar speaker. Then you will Rock the house. Alternatively ask the instrument sub to recommend lowpower tubelike guitar poweramp circuit.
Okay, thank you, and I apologize for posting those threads. I did want to know, in the preamplifier that I have shown above, what exactly are those input and output components?
What do you mean by that question? Historically schematic inputs were often shown on the left side of the schematic and outputs on the right side. Components in those areas are more likely to be input or output components. Its like signal flow is from input to output, which may be depicted as from left to right on a schematic. Where a signal flows into a circuit are where the input components are, etc.
I meant more so what type of components would they be in this case? MTA connector, female guitar output jack, etc....
So, connectors/connections marked as 'in' and 'out' on the schematic?
Usually a guitar preamp input connector is 1/4" mono phone jack. Sometimes it has a switch contact to ground it if no guitar cable is plugged in.
Preamp output connection would depend on if the power amp is in a different chassis, or if its in the same chassis, then if an optional power amp could be used instead and or in parallel with the internal power amp. IOW, it depends on the functionality desired/needed.
Usually a guitar preamp input connector is 1/4" mono phone jack. Sometimes it has a switch contact to ground it if no guitar cable is plugged in.
Preamp output connection would depend on if the power amp is in a different chassis, or if its in the same chassis, then if an optional power amp could be used instead and or in parallel with the internal power amp. IOW, it depends on the functionality desired/needed.
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The amplifier will be housed separately from the preamplifier. I am planning on connecting the output of the preamplifier to the input of the amplifier via some cable (I don't know what kind). In addition, do you happen to have a specific mono phone jack in mind that would go well with this preamplifier input? Wanted to know so that I can create its footprint in Altium.
I believe input of a guitar preamp is designed for a low level (high/low? empedance) microphone signal.
Output from a preamp is a stronger line level signal that fits a standard(ish) line level input of a poweramp circuit.
Often dedicated preamps or pedalboards can also output lowlevel signal for connecting it into the guitar input of a guitar amplifier.
This is not the optimal use of a preamp(sending its output through another preamp), but some does so or have too cause their amp doesnt have a line level input/loop.
Cheers!
Output from a preamp is a stronger line level signal that fits a standard(ish) line level input of a poweramp circuit.
Often dedicated preamps or pedalboards can also output lowlevel signal for connecting it into the guitar input of a guitar amplifier.
This is not the optimal use of a preamp(sending its output through another preamp), but some does so or have too cause their amp doesnt have a line level input/loop.
Cheers!
Standard shielded line level cable. I dont remember if those are 75ohm. Patch cables might be what they are called. I really dont remember if guitar and line level cables has different properties. Hope you get a better answer 😄
Connectors are often 6,5mm or 1/4 inch as Mark says. A 6,5 should sit tighter in a 1/4 inch socket, than the other way round, but I dont know if that will loosen the socket. Two annoyingly close standards. I cant quite grasp which is the wisest choice😄
Cheers!
Cheers!
Most guitar amp stuff uses 1/4" phone plugs/jacks and guitar cable. That's the prevailing standard. Guitar speaker cabs also often use 1/4" phone connectors, but with heavier gauge cable. Go look at Sweetwater or some place like that. Guitar cables are usually designed to be very flexible and have low triboelectric noise.
https://www.sweetwater.com/c786--Guitar_Instrument_Cables
https://www.sweetwater.com/store/search?s=guitar+amp+speaker+cables
https://www.sweetwater.com/c786--Guitar_Instrument_Cables
https://www.sweetwater.com/store/search?s=guitar+amp+speaker+cables
Using nonstandard connectors would mean you might have to make adapters if you ever want to try a different preamp or power amp.
Yeah probably jacks are most common for guitar speaker out and in. Earlier XLR were common for better gear since they are locked and less likely to fall out.
Cheers!
Cheers!