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Is This DAC Suitable For Audio?

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rocket100

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Hello!

So I was wondering if the 12-bit DAC7611 (link attached) could output usable audio? I will be pumping 16-bit (minus 4 LSBs) PCM WAV at 48khz through the DAC. Do you think this will sound like absolute crap? It is going to be used in a sampler, outputted to some speakers. So the quality won't have to be top quality, but it should sound pretty good.

Thanks guys!


https://www.electro-tech-online.com/custompdfs/2012/09/dac7611.pdf
 
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It should sound pretty fine - the Commodore Amiga was only 8 bit digital sound, and that sounded pretty impressive as well (bearing in mind a PC could only 'beep' back then).
 
You mean minus 4 LSB?

There is no link attached but Google readily comes up with the datasheet.

You'll need a buffer if you're trying to drive anything other than a line-input. It's listed current output of 5-7ma is at a 402Ω load, useless for even the smallest of headphones and speakers without distortion.
 
You mean minus 4 LSB?

There is no link attached but Google readily comes up with the datasheet.

You'll need a buffer if you're trying to drive anything other than a line-input. It's listed current output of 5-7ma is at a 402Ω load, useless for even the smallest of headphones and speakers without distortion.

Haha, yea I meant 4. Sorry, it's now attached. What's wrong with me today.

What exactly is an audio buffer? Will buffering the output of the DAC allow me to use it with larger speakers with no distortion?
 
You can easily try for yourself with some free audio software like reaper, where you can convert audio to lower bit resolution.
 
You can easily try for yourself with some free audio software like reaper, where you can convert audio to lower bit resolution.

Great idea! I have tried that recently and thought 12bit @ 48khz sounded superb! But, that is on a computer with a high quality, top of the line DAC. I'm wondering if this DAC7611 would be capable of producing good sound too.
 
12 bit DAC will sound good, as others have said. It's fine to use the 12 MSBs of the data in a 16bit sample.

As with all digital sampling you should pre-process to give good dynamic range (ie; max volume of the16bit waveform) and you might want to look at some WAV processing freeware that does dynamic compression (that makes the quieter bits of the sound louder and keeps the lound bits the same, giving you better sound quality on the quiet parts).
 
So can anyone tell me what an audio buffer does, and if it is used to avoid distortion from this low output DAC?
 
The definition of a "buffer" usually refers to a circuit that has a voltage gain of 1, but higher current gain.

The "resistance" that an input of a non-professional amplifier might look like to the circuit driving it might be around 10,000 ohms. Professional equipment might be 600 ohms, so more current is needed to "drive" the input of the amplifier.

A "Power Amplifier" usually drives a pair of speakers or headphones and has a certain output power and it might be specified as Class AB, 100 W into 8 ohms from 20-20,000 Hz +-0.1 db with <0.5% T.H.D both channels driven. s/n ratio > 100 db.

SO, you get info such as frequency response, what the tested load is, the power and how "flat" the frequency response is and the Total harmonic Distortion.

Buffers are also used to "protect" the expensive part, the DAC from outside the box damage. e.g. the DAC may not be able to drive the input of a powered speaker or an amplifier and defininately it could not drive a set of headphones directly. the "Buffer" or "Buffer Amplifier" may be needed.
 
The definition of a "buffer" usually refers to a circuit that has a voltage gain of 1, but higher current gain.

The "resistance" that an input of a non-professional amplifier might look like to the circuit driving it might be around 10,000 ohms. Professional equipment might be 600 ohms, so more current is needed to "drive" the input of the amplifier.

A "Power Amplifier" usually drives a pair of speakers or headphones and has a certain output power and it might be specified as Class AB, 100 W into 8 ohms from 20-20,000 Hz +-0.1 db with <0.5% T.H.D both channels driven. s/n ratio > 100 db.

SO, you get info such as frequency response, what the tested load is, the power and how "flat" the frequency response is and the Total harmonic Distortion.

Buffers are also used to "protect" the expensive part, the DAC from outside the box damage. e.g. the DAC may not be able to drive the input of a powered speaker or an amplifier and defininately it could not drive a set of headphones directly. the "Buffer" or "Buffer Amplifier" may be needed.



Ah I see! Thanks for the awesome explanation! I checked the impedance of my amplifier I want to drive, it came out to about 12k ohms. Could you point me to a site that has some information on how to build an audio buffer for a DAC? I'm guessing it would be an op-amp circuit? Thanks!
 
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Your DAC is good for about 7 mA which isn't too bad. 1V RMS into 10K really isn't too bad.

The problem is certain OP-AMPs "Sound better" when used for Audio. They can generally be found in the selection guides on the manufacturer's websites. An old OP-amp was the NE5535, but there are better ones that that now.

Here is an article to start: **broken link removed**

Since your starting from the bottom, there are components that are "sprinkled" on a circuit that are not usually shown on schematics. These include power supply bypass capacitors. These are low values capacitors located really close to the OP-AMP power pins. The higher the bandwidth of the part, the easier it is to oscillate.

It's known that Audiophiles will go and replace OP-amps for better sound.

Here is an example selection guide: https://www.electro-tech-online.com/custompdfs/2012/09/slyy013g.pdf
 
Your DAC is good for about 7 mA which isn't too bad. 1V RMS into 10K really isn't too bad.

The problem is certain OP-AMPs "Sound better" when used for Audio. They can generally be found in the selection guides on the manufacturer's websites. An old OP-amp was the NE5535, but there are better ones that that now.

Here is an article to start: **broken link removed**

Since your starting from the bottom, there are components that are "sprinkled" on a circuit that are not usually shown on schematics. These include power supply bypass capacitors. These are low values capacitors located really close to the OP-AMP power pins. The higher the bandwidth of the part, the easier it is to oscillate.

It's known that Audiophiles will go and replace OP-amps for better sound.

Here is an example selection guide: https://www.electro-tech-online.com/custompdfs/2012/09/slyy013g.pdf

Very cool! Would this OP-amp be okay to use with my DAC? https://www.electro-tech-online.com/custompdfs/2012/09/lme49710.pdf
 
The DAC you're using already has a buffer, it's stated specs show that it will give it's 5-7ma rated output into a 400Ω load. You're driving a 10kΩ load, so no additional buffer is required for low distortion.
 
The DAC you're using already has a buffer, it's stated specs show that it will give it's 5-7ma rated output into a 400Ω load. You're driving a 10kΩ load, so no additional buffer is required for low distortion.

As it's pretty essential to have an active low-pass filter after the DAC, then that will buffer it anyway.
 
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