DAC capability?

[verycd]

The internal amplifier is always working. There will always be some noise/distortion from ANY gain stage / amplifier.

The radio only has a headphone output. It is meant to be used as a standalone device, not to be connected to a bigger system. For that you need the Duet (or preferably a Touch)...

Then how should I understand the SB engineer's statement?

"Generally speaking, using a headphone out to drive a line-input will not cause even the slightest degradation in audio. However, if your line-input does not have proper anti-aliasing filters, it could cause an increased noise floor. Typically, this is not much of a problem.

Ironically, high-end equipment could suffer more than low-end equipment in this regard because sometimes high-end designers make the mistake of attempting to preserve perfect frequency response to 40kHz or even farther, which only lets more noise into the system without actually improving anything sonically.

-Caleb"

Could it be the radio headphone has better DAC? The Boom uses Wolfson WM8501 for subwoofer/headphone with -88dB THD (http://www.wolfsonmicro.com/products/dacs/WM8501/) ...What DAC does the radio use for headphone? For the speaker it uses TLV320AIC3104 (TLV320AIC3204 in the Boom).

[Mnyb]

Touch purpose made for conecting to a stereo or home theater, has RCA analog SDIFF digital and TOSlink digital and has a headphone amp too ( of lower sq tha it's rca )

Radio made for standalone use with it's built in speaker has an headphone out.

use the rigth product for it's intended purpose ?
Nobody indeded cheap headphone outputs to be conected to a stereo it can be done but why ?
i get it as a temp solution with an mp3 player at a party...

there is predecessors people always tried to conect boomboxes to thier stereo way back ?

[verycd]

Touch purpose made for conecting to a stereo or home theater, has RCA analog SDIFF digital and TOSlink digital and has a headphone amp too ( of lower sq tha it's rca )

Radio made for standalone use with it's built in speaker has an headphone out.

use the rigth product for it's intended purpose ?
Nobody indeded cheap headphone outputs to be conected to a stereo it can be done but why ?
i get it as a temp solution with an mp3 player at a party...

there is predecessors people always tried to conect boomboxes to thier stereo way back ?

I don't care if it is a cheap solution or not as long as it works. I want to know why people have different opinions on it and why if doesn't work. "Intended purpose"? I admire hackers and look down at commodity worshipers. Hackers not only use but modify a "product" for their own purpose - often unintended by the manufacturers. They are not consumer-slaves. Too bad I know too little to hack the Radio and too poor to use it as a paper weight.

BTW, I returned the Radio and ordered the Touch today. Not following Logitech's logic/intention again, otherwise I should have kept the Radio and bought all other SB models to fill my place. So funny nowadays everyone becomes Apple's volunteer salesperson and their home Ikea display rooms -- AND still feel cool/creative about themselves.

[Phil Leigh]

The DAC chip is not really the issue. The design of the surrounding circuitry is equally important, especially the power supply, grounding and noise suppression strategies.

The Touch has superior sound quality to the radio, boom, duet and sb3; either via it's internal DAC or via an external DAC.

Caleb's statement is basically saying "if you want to, it's ok to connect the headphone output of the radio to a line input..." Of course, one still has to consider levels and impedances.

[verycd]

The DAC chip is not really the issue. The design of the surrounding circuitry is equally important, especially the power supply, grounding and noise suppression strategies.

The Touch has superior sound quality to the radio, boom, duet and sb3; either via it's internal DAC or via an external DAC.

Caleb's statement is basically saying "if you want to, it's ok to connect the headphone output of the radio to a line input..." Of course, one still has to consider levels and impedances.

Thanks, Phil.

I got my touch last night. I noticed that I could control the volume on the Touch when I used line-level output. I was confused since everyone was saying there was no amplification at line level - raw signal therefore no noise or distortion. If the signal of line level does not go through an amplifier then how come I can turn the volume up and down via the Touch?

[Mnyb]

The volume control is digital done in 24 bits before the dac.

[Phil Leigh]

Thanks, Phil.

I got my touch last night. I noticed that I could control the volume on the Touch when I used line-level output. I was confused since everyone was saying there was no amplification at line level - raw signal therefore no noise or distortion. If the signal of line level does not go through an amplifier then how come I can turn the volume up and down via the Touch?

The volume is manipulated digitally using a very high quality method.

[verycd]

Thank you, Mnyb and Phil.