Hey guys.
So I got this older amplifier, one common problem for the amplifier that I have was that it used a tone board made from old opamps and it colored the sound not in the best way. I soldered the audio input directly to the amp boards and it sounds much better.
The original tone board also has a problem that it's potentiometer for volume is dead and a replacement doesn't exist.
Now the amp sounds good as is but i would like to put in a new tone board just in case.
I would need a board that has volume , balance, bass and treble.
Output signal would be in the max 2v level most likely to drive the amp fully.
I'm also bit tired so DIY soldering and making a board isn't what I would want right now.
Does anyone happen to know a good example i could buy and use.
I was looking through ebay and there are some examples using NE5532 and others using LM1036 and similar.
Any advice , recommendation is appreciated, thanks.
So I got this older amplifier, one common problem for the amplifier that I have was that it used a tone board made from old opamps and it colored the sound not in the best way. I soldered the audio input directly to the amp boards and it sounds much better.
The original tone board also has a problem that it's potentiometer for volume is dead and a replacement doesn't exist.
Now the amp sounds good as is but i would like to put in a new tone board just in case.
I would need a board that has volume , balance, bass and treble.
Output signal would be in the max 2v level most likely to drive the amp fully.
I'm also bit tired so DIY soldering and making a board isn't what I would want right now.
Does anyone happen to know a good example i could buy and use.
I was looking through ebay and there are some examples using NE5532 and others using LM1036 and similar.
Any advice , recommendation is appreciated, thanks.
https://www.amazon.com/Preamplifier-Control-Midrange-Controls-Amplifier/dp/B089D988MP/ref=sr_1_5?crid=1CXAUHW5ZJJ9&keywords=tone+control+module&qid=1686674188&sprefix=tone+control,aps,137&sr=8-5
But maybe you should consider a digital solution, ie run everything through a mini-PC. All my music is stored and played by a computer, so there is no need for a pre-amp, and 400+ albums is only about 40G of disk space. You can use a fancy DAC if you like but most sound cards are good enough for me.
But maybe you should consider a digital solution, ie run everything through a mini-PC. All my music is stored and played by a computer, so there is no need for a pre-amp, and 400+ albums is only about 40G of disk space. You can use a fancy DAC if you like but most sound cards are good enough for me.
For tone controls using FET input opamps is usually the way to go, no need for DC-blocking capacitors on the pot wipers to avoid crackle. If you do use a board with bipolar input opamps make sure there are such blocking caps on the wipers. Some circuits assume FET opamps and cannot take bipolars.
I would avoid any preamp that uses the LM1036. It has oscillation problems. See
https://e2e.ti.com/support/audio-group/audio/f/audio-forum/386223/lm1036-oscillation
The ESP preamp boards are reasonably priced and their assembly instructions are comprehensive. For another possibility that may be easier to use in your situation, consider:
https://sound-au.com/project88.htm
https://e2e.ti.com/support/audio-group/audio/f/audio-forum/386223/lm1036-oscillation
The ESP preamp boards are reasonably priced and their assembly instructions are comprehensive. For another possibility that may be easier to use in your situation, consider:
https://sound-au.com/project88.htm
If you actually want a balance control, it can be simply added to the volume controls.
The LM1036 has dreadful THD, as might be expected from any kind of voltage/current controlled attenuator.
TI has some decent digital attenuators: https://www.ti.com/audio-ic/amplifiers/volume-control-ics/products.html
The LM1036 has dreadful THD, as might be expected from any kind of voltage/current controlled attenuator.
TI has some decent digital attenuators: https://www.ti.com/audio-ic/amplifiers/volume-control-ics/products.html
I recommend LM1036 as I have experienced several DIY projects using it. It provides good-quality audio and nice coloration to the audio.
Also, you could customize it easily based on your application needs. Read the article I've written about it: https://medium.com/@rasansmn/fine-t...sting-the-tone-controlling-range-674d2db8561a
Also, you could customize it easily based on your application needs. Read the article I've written about it: https://medium.com/@rasansmn/fine-t...sting-the-tone-controlling-range-674d2db8561a