Greetings!

I’m trying to compile a few Hemi-Sync® CDs onto one MP3 CD so I could listen to them on my portable (Sony D-CJ01) without having to switch ‘em back & forth. Bitrate here is less of a concern than quality since we’re dealing with the effects on states of consciousness produced by the binaural beats, the product of complex multi-layered patterns of sound frequencies.

I’ve just begun using EAC v0.9b4 with LAME v3.93.1, and have blind-tested both --alt-preset insane and --alt-preset extreme settings on regular music with different results. Using the Sennheiser HD580 headphones, I notice some tracks seem to be more “fluid” with --ape than with the --api, while most other times the music are arguably indistinguishable.

With the regular wav->mp3 music I’m not too worry about the accuracy than with the brain/mind CDs. The last thing I want is to adversely alter my brainwaves listening to the Hemi-Sync® CDs because some sound frequencies were not accurately included during compressions. Anyone out there with experience on the best encoding to use for this type of CDs? This whole mp3 encoding thing is rather new to me, so any advice will be much appreciated!

--api should be the best.

If the CDs are available as cassette tapes, we all know tapes ... well.... (someone tell me my assumption of commercially available tapes and not the metal/chrome ones not reproducing high frequency is wrong.)

-api ... well, that's why it's called insane.

If your portable can handle it, --freeformat -b 640 is not only insane, its ridiculous.

Well, I think MP3 may not be the way to go. It seems to me like you are looking for some subliminal effects from your music? MP3 has been designed from day one to REMOVE everything you are trying to preserve. Sure, MP3 may very well work, but it may be very difficult for you to figure out if it's working for you.

All of the brainwave entrainment soundtracks that I have are in CD format. High frequency, as I was told, is not the important factor behind these neuro-audio technologies, tho I think the effect of the entrainment stimulus would be reduced if the highs of the audio spectrum from the original were filtered out or altered. Most of the producers of this type of neuro-audio CDs are not completely forth-front with what’re exactly in them, except in disclosing that the technology behind it was developed by the US Government and has only been recently de-classified. So you're right! It is difficult to figure out what to preserve and what not.

I do know, however, that most neuro-audio CDs involved are using lower carrier frequencies masked by environmental sounds and music to stimulate brainwaves. The lower frequencies are usually in the range of 60~ to 250~ Hz. Does anyone know what are the frequency cutoff limits for mp3s? I know that mp3 encodings filter out some of the extraneous highs and lows of the audio spectrum. What mp3 considers as extraneous however may be a vital element here for the brainwave entrainment stimulus.

I’m certain if one has the means (equipments/software) and the know-how, the exact measurements could be done for a before-and-after to see the range of frequencies effected by the encodings. Are there any programs on the Internet that one could download for this purpose? There must be someone out there who has encoded this type of soundtracks into MP3s!!!

--aps in all likelyhood would probably be fine. I encode Bass 305 CDs. They have ultra-low frequencies.

And from what I know about these brain music stuff, no, they don't have high frequencies that would really matter.

Brain music - in a few words - stimulates you. If you feel better, think better, work better, etc better, then its working.

You could probably do just as well in an anaechoic room (one that is completely silent.)