Am Sa 9. Februar 2008 schrieb Clarke Wixon: > joerg <[EMAIL PROTECTED]> writes: > > > The amp is for the speaker(s) only, and GTA02 has only one of > > them (mono). That's fine, for one good speaker will yield a better sound than > > 2 small ones. > > Unfortunately, I don't think we're getting "one good speaker" in the bargain. > The second speaker was removed to make room for WiFi, so the remaining speaker > is likely to be of comparable (identical?) quality to half of the original pair.
:-( Anyway, 2 speakers don't make a stereo output yet, when built in such a small case. So it's not so bad to lose one of them. > > But you're right, the headphones should still be fine. However without circuit diagrams, we can't say for sure what they 've done and why. Seems i was wrong with direct connection of HPh to codec chip. see spec of wolfson mixer codec chip: On-chip Headphone Driver with cap-less output option - 40mW output power on 16Ω / 3.3V - with 16Ω load: SNR 90dB, THD –75dB - with 10kΩ load: SNR 94dB, THD –90dB On-chip speaker driver with 0.5W into 8R I don't know why they use a dedicated amp LM4853, which is good for nothing it seems: near same power, mono *OR* stereo output, no capacitor-free bridge out for stereo. Additional parts needed for headphone detection to system. Sigh... j _______________________________________________ OpenMoko community mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/community
