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NauticusLX
2007-03-27, 23:50
I discovered that if I run a wire from the audio-out of the SB3 to the line-in of my (Pogo) MP3 player/recorder, the recording level is...perfect! Which is amazing since with the Pogo, it's impossible to set or adjust recording levels, at least not directly. For example, when I use my Pogo to record from my stereo (when transferring analog records to digital), I need to set record levels with the vol, treb and bass controls in the stereo console (which requires a LOT of experimentation). But this is the first time I tried a digital recording directly from the SB (I've recorded with audio tape, but through the mini system into which the SB is plugged-which has auto record levels). Anyway, so how is it that the signal level of the audio out of the SB3 is just right for the Pogo device to record? Or would this "natural compatibility" be the case if I plugged the Pogo into the output of any other digital device?

Also, if the audio source is, say, 128 kbps, does the recording need to be at least 128, or exactly 128, to get the highest quality recording?

ceejay
2007-03-28, 00:21
If you have used the analog outs from the SB into your device (sorry, never heard of it) then any level compatibility is purely a matter of chance.

If you are using the digital SPDIF out from the SB into a corresponding digital input on your device, then there is no chance involved, you are getting a straight digital transfer.

My guess from your other comments, though, is that you are using an analog transfer. Be aware that you are heading for some very low sound quality if you start off with a low-quality source like 128kbps: the sound will have been compressed once to get to that level, then the SB will be uncompressing it to give you an analog signal, then your device will be compressing it again. This will nearly always give bad results. There is no significance to the exact bit rate you compress to.

Does this device not have the ability to transfer mp3 files directly?

Ceejay

NauticusLX
2007-03-28, 20:03
Yes, I do have to turn the volume up a bit more than usual, after recording as I described in my initial post, but besides that, the sound quality is "great" (sound quality is always a subjective matter). But I hadn't thought of using the digital optical output! I forgot it had one. But the "line-in" jack in the recording device is analog (I think), so does that make it impossible to make a digital, real-time recording? Are there cables that have one end digital and the other end analog? A thought that occurred to me after my inital post was, is the term "recording level" irrelevant to the digital signal? Or is bit-rate the only property of the digital signal that is relevant? Maybe that's why there's no recording level control in the Pogo DAP (digital audio player), because the makers asssumed the incoming signal, during recording, would be digital.

ceejay
2007-03-29, 00:22
- A cable that had digital at one end and analog would be a DAC, and no "cable" is going to do that for you!

- "Recording level" is indeed irrelevant to a digital signal, but that's not what you have here. If you are taking the line out from the SB then you're in analog mode.

- I'm not quite sure what this Pogo device is, but if its the one I found after a quick google then it has only an analog line in, no apparent way to transfer mp3 files.

- I'm not sure how "perfect recording level" in your first post is consistent with "have to turn the volume up a bit more than usual" in your second, but if you're happy with what you've got then leave it alone!

- if there's no recording level control on the device, its because its "cheap", not because it doesn't need one....

- why anyone would make a digital music player that doesn't have the capability of downloading mp3 files completely escapes me!

- BTW, is it one of these? http://www.engadget.com/2005/03/09/pogos-radio-your-way-lx-radio-centric-dap/
If so it seems to have an SD card facility, if you have an SD card reader on your PC you could use that for transferring mp3s.

HTH
Ceejay