Using External DAC/AMP with an A/V Receiver?

[Supernova58]

I have a Fiio BTA30 DAC/AMP (bought mainly for my PC) but noticed that when I connect my TV optical output to it and then from it to my A/V receiver, the sound quality improves noticeably compared to when my TV is directly connected to the A/V Receiver.
My question is whether it is worth spending on a good DAC/AMP to use externally between my TV and A/V receiver (which is an old Yamaha RX-477), or if I upgrade my A/V receiver to a much newer and better model, I would get the same quality and would not need any DAC/AMP in the middle? In other words, does a newer and better A/V receiver naturally provide better DAC/AMP that using an external one would be totally unnecessary?
Thanks in advance for sharing your opinion and advice.

 

[twsecrest]

What sources do you connect to the RX-477?
Hopefully HDMI connected from the source, to the RX-477, than HDMI from RX-477 to the TV?

 

[Supernova58]

What sources do you connect to the RX-477?
Hopefully HDMI connected from the source, to the RX-477, than HDMI from RX-477 to the TV?

Only a TOSLINK Optical connection from the TV to the receiver.

 

[DVDdoug]

There shouldn't be a difference...

There could be some different processing in the AVR with analog vs. digital inputs, but I wouldn't expect that.

When you're comparing, make sure you are listening at the same volume (as much as practical/possible).

An AVR has the advantage of being able to decode (and optionally downmix) all of the surround formats whereas most stand-alone DACs only support uncompressed stereo PCM. But if your TV is set up for PCM stereo that won't make a difference.

Personally, I've never owned a stand-alone DAC and I've never heard a difference or defect from a DAC, except I once had a computer with a noisy soundcard. Nor have I ever tried to hear a difference or defect. Usually when there's something wrong, or something I don't like, it's the recording... or the pitiful sound system in my car.

 

[Supernova58]

Thanks for the comments, but they don't actually answer my question.