The first rule of fight club is nobody talks about fight club. I learned not to talk about how good Bluetooth has gotten because it's not generally considered relevant in hifi. I've been using it a lot for systems I build for friends as an entry level source. I've been using iFi Zen blue as it is cheap and cheerful. Easy to use too.
Another thing that is not talked about is the Schiit Urd cd transport and usb hub. See post 121; https://www.head-fi.org/threads/sch...bable-start-up.701900/page-8077#post-17642459
I use BT when it's convenient to do so. Same with BT headphones; hate holding the phone up to the side of my head. I assume the radiated power from the headset to the phone, is somewhat less than from the phone to the cell tower...
One thing I dont understand is when people claim there's BT "compression". What compression; they have to stuff 16 bits into 12? I'd be inclined to believe in the latest incarnations, audio bit width is zero problem. "Compression" still an issue these days?
One thing I dont understand is when people claim there's BT "compression". What compression; they have to stuff 16 bits into 12? I'd be inclined to believe in the latest incarnations, audio bit width is zero problem. "Compression" still an issue these days?
I'm stuck with BT for one of my class-D modules after tripping over a headphone cable and wrecking the jack. It's a cheap import, so SQ was unlikely to be great to start with, but it was noticeably better through the HP jack.
Apart from signal dropping and occasional driver issues, or forgetting that device X was already paired when trying to connect Y, my biggest gripe is with handling of volume control. What er, n00b, came up with the bright idea of relying on the digital volume control in the phone or sound card, which loses 1 bit of resolution (from a likely starting point of 24) for every 6 dB of attenuation, and only then sends the already-degraded signal over Bluetooth?
The receiving device only seems to have analogue volume, so it relies on the sent signal to be pre-attenuated, and it's not smart enough to use meta data for its own digital volume.
So in the worst case, the analogue pot on the amp is turned up while the phone/PC turns it down, and the output is full of obvious artifacts like abrupt muting between words, like some sort of overzealous hiss reduction.
Apart from signal dropping and occasional driver issues, or forgetting that device X was already paired when trying to connect Y, my biggest gripe is with handling of volume control. What er, n00b, came up with the bright idea of relying on the digital volume control in the phone or sound card, which loses 1 bit of resolution (from a likely starting point of 24) for every 6 dB of attenuation, and only then sends the already-degraded signal over Bluetooth?
The receiving device only seems to have analogue volume, so it relies on the sent signal to be pre-attenuated, and it's not smart enough to use meta data for its own digital volume.
So in the worst case, the analogue pot on the amp is turned up while the phone/PC turns it down, and the output is full of obvious artifacts like abrupt muting between words, like some sort of overzealous hiss reduction.
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Bluetooth normally doesn't transmit PCM audio as PCM audio, but as something with a reduced bitrate. As far as I know, all Bluetooth audio devices have to support a rather bad subband coder/decoder with a substantial delay, the SBC CODEC in Bluetooth jargon. Some support other CODECs such as Apt-X or Apt-X LL, which has both a better sound quality and less delay. Apt-X is a variant of ADPCM, meaning it is also not bit accurate.