Best Format for Recording FM Radio

[viiv]

Getting a deck and hooking it up to a stereo with good quality AV cables is something I am going to be doing primarly for radio recording off FM. Now if I'm using the latest ATRAC Type-S but not HI-MD equipment, which format is best for recording music off FM radio? I don't want the encoding rate to be too high versus the quality of FM because then I would be wasting space. At the same time too I do not want to use too low of a bitrate in I would lose quality. So of the 3 formats which is best for FM musc recording, SP, LP2 or LP4? I know SP is 292kb per second ll the way down to LP4 which is 66kb per second. I guess it would be helpful to know what is the FM equivalent of bitrate vs ATRAC. I mean if it was lower than 66kb then it would be a waste of space to use anything higher than LP4. If it is a higher equivalent than LP4 than LP2 should be used to not lose quality I guess. I doubt though that it's equivalent quality would be better than LP2 though. So what do you guys think?

[The Low Volta]

well, it's not really as simple as 'matching bitrates'

- FM uses a 'lossily compressed' signal which means that bits are cut out

- recording in atrac means another cycle of lossy compression so even more bits are cut out (as it will treat FM as a full info source just like a CD)

you are always going to get lesser SQ than the source (in this case FM, which isn't great to start with)... to get the best SQ (i.e. as close to FM as you could) you should use the highest bitrate SP (as it cuts out less info than the others). IMHO, if you know you're going to tape radio and realize that SQ won't be really good, SP is a waste of space and I'd personally use LP2... but it all depends on how close to the original FM-signal you want to stay

PS: I don't know whether it is correct to state that FM uses a lossily compressed signal, but from the receivers' point of view, it is 'the same' (bits of info left out whether on purpose or through imperfect transmission) and perhaps even worse, as a good encoder doesn't introduce as much artifacts/hiss/static etc as FM does (or at least does here in Belgium)

[ATELETRONICS]

trust me just use lp2 it will be very close to what you want.

[jonny mac]

You're never going to get fantastic rsults from FM as the signal is not the best quality anyway so best to us LP2, I'm pretty certain you will hear no difference at all. FM is not compressed at all but it does suffer from interference from other radio sources.

Go with LP2.

[netmduser]

how about lp4, that should be sufficient for fm? Isn't the fm signal combined into 1 channel similar to lp4 encoding?

[KJ_Palmer]

LP4 would just degrade the signal even further. Personally, I'd use SP when recording on my deck in order to be able to use SF Edit to tweak the recording levels afterwards. LP2 would probably be the best 'other' option in this case.