Would I be correct in assuming that using the Toslink in this setup will also isolate the noise from the external hard drive or any other connected devices (I'm guessing that's right and maybe the SLA for the external drive was a separate thought).
Hi Fork,
Welcome to audiocircle and the RWA forum!
Good question! Dirty power from a computer can result in degraded S/PDIF digital output signal... no matter if it is transmitted via coax (electrical) or TOSLINK (optical). With regards to transmitting this digital signal, with TOSLINK you can at least isolate any potential ground noise or hum. I am not saying that Toslink is superior to coax and vice-versa. If you have the chance, I recommend you try both and see if you can hear a difference and decide which one you like better. This goes for any dac that offers these digital inputs ... not just Isabella's
Isabella's dac will also offer a USB input. The USB signal is converted directly to I2S to feed the Isabella's dac chip. The signal is not converted to SPDIF and then to I2S.... it gets converted directly to I2S. This is the cleanest transfer and while the coax and optical inputs still sound very good, the USB input o(I'm using a MacBook's USB output to feed the Isabella's dac) is the best I've heard!
I'm wondering if a desktop-WiFi Transmitter-Squeezebox-Toslink-Isabella chain (as opposed to a laptop-USB-Isabella chain) creates any compromises in the audio quality, like added Jitter from the Squeezebox or something like that.
The Squeezebox's SPDIF digital outputs offer low jitter specs and you'll get very nice results, but as mentioned above, use USB for the very best results.
Best regards,
Vinnie
