RPI dual mono DACs related question

Darjus

Member
2017-05-02 10:33 am
Hi guys,
I have a wish to use RPI in mono mode. Connecting a single speaker and getting all sound (not missing left or right channel). Aim is to use it on a single car dash speaker (vintage Alnico) for mids and highs. There is software solution on combining both channels but i would like to go with DAC based.

I see on the market there is some Dual Mono Raspberry PI dacs. Durio sound , Ian Canada one, and expensive ApplePi. If I would use any of these DACs, would it be the case that i can connect to any of two RCA outputs and will hear the same sound (now splitting to L+R done)?
 

Darjus

Member
2017-05-02 10:33 am
Well its one of those, however my question is more related whether i can get mono from it. For example, if use only one of RCAs from DAC, lets say left, will i get full sound? it won't be as part goes to speakers, and part stays in Right RCA plug? :)
 

DRONE7

Member
2008-08-21 11:12 am
can get mono from it. For example, if use only one of RCAs from DAC

No...and yes. The dual mono refers to two separate chips, one for each channel. eg Allo Piano 2.1
So a stereo feed to that i2c hat will result in a stereo output with each chip handling only one channel.

However, you should be able to configure a mono output from upstream...ie the RPI. Distros such as MoOde have a mono option ootb . (see attached config)
Then you could use any DAC-Hat.

moodeaudio.org
Moode Forum
 

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Darjus

Member
2017-05-02 10:33 am
thanks for the reply, that actually answers the question about DACs - that i cannot just change DAC to get mono output.

Yes i am familiar with the software option for this, but what do you think would be worse for sound quality? to use software to merge stereo to mono, or hardware (with resistors as in picture attached )?
 

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If you need only one channel out of a stereo DAC, you can merge the two analog outputs to average their individual distortions. You will not hear any difference, but it may be measurable.

Plus feeding both channels with the same mono signal - i.e. making the sum/2 in software. It is a trivial operation.