Analogue line level recording with inexpensive handheld MP3 players

Recording with software on a computer provides an alternative to hand held MP3/WMA recorders. In this article, the recording potential of inexpensive hand held records will be examined.

Hand held recorders may suffer from a number of problems. The most obvious limitations of hand held MP3/WMA recorders are likely to be:

* Poor battery life. Sure, this can be rectified by fitting a replacement, but doing so can be a potentially risky & difficult task – assuming one can even find a replacement battery!

* Limited storage capacity for long recordings. Fixed capacity recorders force users to only keep a very small selection of music or videos on the player, otherwise there is inadequate recording space available when needed.

Other potential headaches experienced with portable MP3/WMA recorders include:

* Automatic Level Control (ALC) is implemented for recording, which is not ideal for all programme material. ALC artificially restricts the dynamic range of the recording. Limiting dynamic range is considered undesirable for music, although it is applied widely to radio broadcasts. A pair of RCA Line Level Audio Attenuators may be required to ‘tame’ audio output levels from analogue components (e.g. Harrison Labs’ manufacture 3, 6 & 12 dB models, which retail from $34).

* Encoding quality. Line-in recording is frequently restricted to relatively low bit rates such as 128 kbps, 160 kbps or 192 MP3 compressed audio recording. These bit rates are not ideally suited for recording music. Gabriel Bouvigne recommends 256 kbps MP3 as a minimum encoding rate for music. Today, even sub-$100 cellular phones support lossless FLAC audio. Does compressed audio files (such as open source MP3, Apple’s AAC or Microsoft’s WMA) still offer relevance?

Creative & Samsung Hand held MP3 Players

Perhaps two of the most suitable MP3 players for recording include the Creative Muvo Vidz & Samsung YP-T8 MP3 players. Both are available in 1 GB capacities. This capacity means these devices are capable of performing recordings from analogue components lasting over 11 hours at 192 kbps MP3 (their highest recording bit rate). That would fill over seven 90 minute cassettes. Unfortunately, these players are extremely rare to find & cost over $80 in the second hand market.

1 GB capacity Creative Zen Neeon 2 models fit 16 hours of recordings at 128 kbps WMA (their highest recording bit rate). These are readily available, refurbished by the manufacturer priced from $45 (1 GB) up to $85 (4 GB).  It is difficult to overlook the fact that the 4 GB model will fit an impressive 66 hours of recordings (128 kbps WMA), but Creative’s Zen Neeon series cannot be recommended by the author. This is due to unreliability of the hardware, in particular the widespread reports of hard drive failures. The author’s Neeon 1 model will not start up.

Olympus Hand held Recorders

The Olympus WS-832 & WS-833 (from $160 new) record with PCM format as well as 256 kbps MP3 but probably audibly wreck bass response (e.g. timpani, kick drum & bass guitar) because of a sharp 40 Hz cut-off. The specified PCM recording frequency response is only 40 Hz – 21 kHz. Such a shame, because these voice recorders also feature fully adjustable recording level control.

Mini Disc Portable Recorders

Mini Disc portable recorders which use ATRAC implementations also suffer from similar restrictions on quality like MP3/WMA. The exception is if one owns the relatively rare Hi-MD recording models (examples, pictured below) & can also readily source affordable discs.

Sony MZ-RH10 © 2006 Dietrich Liao.

Sony RH-1 © 2012 Jaen Yu.

Example: Recording with Zen V Plus & Samsung Yepp T7

Personally, the writer has enjoyed immensely recording on these tiny devices over the last decade. The primary advantages are due to their size. An honest evaluation of their performance is warranted.

In theory, portable digital recorders should perform better recordings than modern compact cassette boom boxes. Modern boom boxes incorporate poor quality recording heads with rapidly falling treble response over 10 kHz, not to mention poor wow & flutter performance (due to poor quality generic mechanisms) compared to the relatively high quality found in boom boxes during the 1980s & 1990s. During this period, some of these at the high-end boom boxes such as the 1990 model AIWA Strasser CSD-SR8 (photos here & here) featured Dolby C & Dolby B noise reduction as well as manual recording level control. If functional, these high-end boom boxes command very high prices today on auction sites.

Take, for example the Creative Zen V series recorders which are no longer manufactured, but still sold (currently priced from $80, manufacturer refurbished).

Zen V © 2007 Brian Barnett.

When launched in 2006 for $230 USD the Creative Zen V Plus received favourable reviews. The playback audio quality was very good on the Zen V series with low levels of noise & distortion reported during measurements. The Zen V series uses the Media Transfer Protocol (MTP) to transfer video & audio files (including uncompressed PCM, as well as compressed MP3/WMA) in Microsoft Windows operating systems.

Creative’s Zen V players (as well as the Zen Neeon 2, mentioned earlier) would be more useful if the player did not encode line-in recordings in 160 kbps WMA format. Today, WMA offers less playback support than MP3 & AAC files so the future is not rosy.

Exacerbating this, is the fact WMA recordings are unsupported by loss less MP3 software editors such as MP3DirectCut if one needs to edit the recording. Converting recordings to PCM alleviates this but doing so offsets the primary advantage of compressed audio, the small file size!

Samsung YEPP YP-T7 recorder in the bottom left © 2005 Josh Bancroft.

The other problems encountered when analyzing software measurements suggested that hiss & clipping may be problematic when recording on the Creative Zen V Plus & Samsung YEPP (Young Energetic Personal Passinate) model T7, pictured above. A Sangean PR-D8 (chosen because it supports 192 kbps MP3 line-in encoding) was used to double check any inconsistencies found with recordings made on the Zen & YEPP MP3 players.

Hiss

Surprisingly, recordings on the Zen exhibited 15 dB more high frequency noise (hiss) in a recording of silence compared to one made on a laptop sound card. These (admittedly imperfect) software measurements were of noise floor, made in Root Mean Square (RMS) amplitude. Another crude inspection using the meter (maximum range: -96 dB) suggested approximately 10 dB more noise in the Zen recording of silence.

Recording nothing ain’t so silent on the Zen! © 2016 FM DXing.

The Samsung YEPP recordings exhibited less than 3 dB more noise in recordings of ‘silence’ than the sound card which was expected – so very close to the performance of the sound card. Of three hand held recorders by different manufacturers, the YEPP outperformed all others in tests.

Recording nothing ain’t so silent on the YEPP either! © 2016 FM DXing.

Regardless, the A-weighted Signal to Noise Ratio (S/N) figures for analogue (line-in) recording from the sophisticated Wolfsen Microelectronics, Telechips, Texas Instruments & SigmaTel’s D-Major ‘codec’ Integrated Circuits (ICs) utilized inside these MP3 players do suggest 80-85 dB as minimum figures. But the noise is higher than the IC measurements because other hardware (such as LCD screens & poor component shielding) in the players may produce additional noise – perhaps even the encoding software. Hence, the actual real world S/N figures for recordings is typically lower than the ‘codec’ figures.

At this point it may be useful to compare more closely these low-cost digital recordings with their vintage analogue counterparts. The A-weighted Signal to Noise Ratio minimum figures for compact cassette tape recordings are as follows: tape recordings encoded with the commonly found Dolby B provide 68 dB S/N. The high-end, (but both less compatible & prevalent) Dolby C provides 78 dB S/N. The relatively rare high-end Dolby S provides 80 dB. There is likely to be negligible variation between ‘Dolbyized’ recording decks.

JVC cassette deck © 2009 Neil.

1978 vintage Akai GXC-760D cassette deck © 2014 FrankPR.

Modern low-end compact cassette recorders may not offer noise reduction provision, including many portable boom boxes & light weight mini systems. In fact, the new Prince re-issue cassette albums that were manufactured in the United States in latter half of 2016 are not recorded with Dolby B noise reduction for this reason; unlike vintage pre-recorded cassettes.

Yamaha PC-8 portable system with Dolby B & C noise reduction.

Sony FH-7 MkII portable system with Dolby B & C noise reduction.

Without noise reduction, the minimum Signal to Noise Ratio (A-weighted) is 58 dB, even worse on some machines with cheap mechanisms with figures as low as 52 dB S/N. In theory, these inexpensive modern tape recorders should create recordings with considerably higher hiss than is possible with digital recording using the aforementioned ‘codec’ ICs.

Clipping

Worse than noise added, a test recording from a compact disc component (original CD pressing of Roy Orbison’s Mystery Girl) showed clipping  in all software & also failed the ABX recording level tests, with the recordings on both the Zen & YEPP peaking in excess of -3 dBFS. This is despite the recording being made well below the peak (red coloured) levels on the recording level display. 3-6 dB RCA Line Level Audio Attenuators do tame output levels so the clipping does not occur, but are an unnecessary expense.

The process of encoding to compressed audio formats may cause clipping, so turning the input volume down may not necessarily address the problem in every instance. In those circumstances, the clipping should be be tolerated – consider it to be a normal artifact of the encoding process. Be that as it may, in the few tests performed with these recorders, clipping could be entirely avoided in the WMA or MP3 by simply lowering the recording volume using an in-line Level Attenuator.

Frequency Response 

Let’s examine the frequency response of recordings in detail now. Particular detail will be paid to how analogue portable recorders perform as well, which will serve as a benchmark.

The encoder on the Zen will also discard frequencies above the sharp 15.5 kHz cut off so is most suited for FM radio recording. FM broadcasts exhibit approximately the same cut off. Frequencies also sharply rolled off after 16 kHz on the YEPP recordings.

Note that for digitally recording local FM broadcasts, the ADS Tech RDX-155 ($20, new) is the better route, due to the provision of lossless 192 kHz sample rate PCM recording. This Silicon Labs’ SI4701 tuner (marketed as ‘Instant Radio’, above) is a USB computer tuner which requires antenna modifications (including soldering) for connection to a rooftop antenna.

Two test signals were recorded in the Zen. On the left is the original, on the right is the copy. This spectral analysis illustrates the ability of the recording to capture the original.

In addition, an eighties rock song was recorded in the Zen.

These measurements are not considered to be problematic; many quality cassette recorders gently roll off content after 18 kHz. It is often suggested that unless one makes recordings with considerable of gong & cymbal percussive content, such high frequency roll off may not even be noticeable.

Vintage JVC one-piece boom box © 2011 Neil.

One low-end boom box tested (manufactured in the late nineties) exhibited little high frequency response after 14 kHz, whilst one high-end boom box tested (manufactured in the mid-eighties) lasted beyond 17 kHz. These had been professionally serviced with new belts fitted as necessary, the digital recorders do not require ongoing servicing.

Below is an example of a high-end boom box recording using Dolby B noise reduction & a medium grade TDK AD tape. Again, on the left is the original, on the right is the copy. Strikingly, the cassette recording significantly outperforms the Zen recording, shown above. But remember this machine has been well maintained; vintage analogue equipment requires ongoing attention if it is to continue performing close to the original manufacturer specifications.

Modern boom boxes offer considerably worse compact cassette recording performance than these (above) examples. For instance, observe (below) the performance of a regularly serviced, low-end boom box compared to the Zen digital recording. Whilst there is slightly higher frequency response on the cassette recording, this analogue quality improvement is offset by more hiss (evident in blue, above 12 kHz) than the Zen digital recording, as the low-end boom box recorder provides no noise reduction. In fairness, compression artifacts affect the digital recording (due to low 160 kHz encoding bitrate). Depending on the genre of music being recorded, these digital noises may be as irritating to listen to as audible hiss. It is a matter of personal preference as to which of these two low quality recordings is more natural sounding to listen to.

Modern boom boxes (marketing pictures appear below) include the Panasonic RX-D55 (from $182, new) & Sony CFD-S50 (from $117, new).

Panasonic RX-D55 boombox.

Sony CFD-S50 boombox.

Extremely poor recording performance with modern boom boxes is probably because the demand for quality is not strong, like it was in the eighties & nineties. Although currently fashionable amongst indie recording artists, these plastic boom boxes cannot be even recommended for the simple task of playback of pre-recorded cassettes! Today, manufacturers’ research & development priorities are likely to be focused on digital recording.

Final comments

It is hard to dispute that these portable hand held recorders can offer immense convenience & are likely produce higher fidelity recordings than modern low-end boom boxes. Firstly, a laptop or boom box recorder is much larger in size. Secondly, laptops must be regularly maintained with software & perhaps to a lesser extent, hardware upgrades. Boom boxes also require maintenance such as regular head cleaning & very rarely, belt replacement. Ongoing maintenance for these hand held recorders is negligible. Those commitments might include regularly charging the battery & very rarely, updating firmware!

However, the testing of Zen & YEPP indicated evidence of noisy or poor quality A-D conversion in these recorders, compared to even the most basic on board sound cards found in computers. Audio clipping is also a significant potential problem, especially for careless users. The Automatic Level Control cannot be blindly relied upon during recording. These factors potentially contribute to noisy, harsh-sounding or distorted recordings.

Accordingly, the next topic for discussion is the use of simple software for portable recording on superseded or surplus laptops. It is suggested that recording with a computer may allow better quality recordings than hand held recorders because of the less restrictive encoding options, full adjustment of recording levels & options to plug in high-end external sound cards into the computer. But it can be tricky to find free software that simplifies, rather than unnecessarily complicates the process!

Samsung Yepp MP3 recorder

This terribly rare species is fantastic for making MP3 recordings via line-in. In addition, playback of the highly-rated aoTuV (Aoyumi’s Tuned Vorbis) Ogg Vorbis files is supported.

If this little blogger didn’t already own the same model (except in the smaller 256 megabyte capacity) the above Ebay offer would be snapped up quickly. This species is extinct.

Here is a photo of the Yepp feasting on a recording. Delicious. Further information can be found here.

A new Yepp T8 (512 megabytes) sells on Ebay for about $130. Like the T7, that species is also extinct.

3 machines in 1: Teac AD-800

The Teac AD-800 is an eye-catching hifi component which costs roughly $300 Australian dollars delivered when purchased from on-line sellers in the United States.

Overview of features

This device plays MP3 tracks from a USB device, MP3 & CD tracks from a CD-R or CD-RW & analogue tracks from compact cassette. What is instantly impressive with this highly-rated component is the full remote control for all functions of the USB, CD & cassette. Recording can be performed via remote control. The machine will record to USB from a CD, cassette or an external analogue source such as a turntable or FM tuner. In addition, Timer Recordings to cassette can be performed. The machine uses an adjustable recording level which are rarely found on portable MP3 recorders but can be important to maintain distortion-free digital recording.

The cassette section is full-logic with auto-reverse & pitch control which would be familiar to disc jockeys & announcers. Pitch control raises or lowers the playback speed by 10 percent. Pitch control can be valuable ‘if it does not sound right to you or does not match the playback speed of the original vinyl record it was taped from,’ according to an anonymous tester.

MP3 recording

On closer inspection, it seems that the machine is far from perfect. 128 Kbps MP3 recordings may not do the MP3 algorithm justice. Audiophile Zomax writes in his review:

I realized when playing back the MP3s on my computer through headphones: 128 [Kbps] does not cut it. Edith [Piaf records] actually sounded fairly good (probably given that the original recording already sounds like it’s am radio), but after I recorded some Nirvana, there was no ignoring the telltale wishy washy cymbals of low-rez digital. Unfortunately 128 [Kbps] is the only option — this will obviously be a deal-breaker for anyone looking to make serious digital recordings of their analogue sources.

192 Kbps MP3 recordings are subject to significant loss of high frequency sounds above 16 KHz, while 128 Kbps MP3 recordings hit the dust above 14 kHz.

Will Ryu of Ars Technica explains the inadequacy of 128 in the modern environment where a 2 GB Secure Digital storage card costs less than a pint of lager:

…At 128 [Kbps] I had no trouble discriminating the CD from the MP3s. At higher bit rates this became increasingly more difficult, but even at 256 [Kbps] I believe I could hear differences by concentrating on certain parts of the track which were more susceptible to encoding error.

..The listening conditions for MP3s have changed, but the standard bit rate of MP3 encoding hasn’t. If you can’t hear the difference between 128 [Kbps] & 192 [Kbps] then congratulations, the more hard disk space to you. But if you can, why settle for 128 [Kbps]?

Recently, three music writers for the Guardian tested the MP3 format:

In my view, there was a real discernible difference between the MP3 or CD and the studio master tracks…

What was very apparent is just how bad a poor-quality MP3 sounded, how good a 320kbps MP3 and CD sounded, and how cutting out the middle man in the audio production chain with a studio master could have unexpected results.

Cassette playback & recording

The Teac combo’s flat response between 50 Hz – 12 kHz with playback of metal cassette tape is barely satisfactory. Wow & Flutter (speed variation) is 0.25 percent using the standard Weighed Root Mean Square measurement, a specification not comparable to the better decks.

By frequency response, this is what we are talking about. The spectrum from Programmer & Electronics Engineering Lecturer Albé Bredekamp, shows a white noise signal recorded onto Philips Chrome tape analyzed using Audacity software. The frequency response is measured using a signal at -20dB.

An analysis of 13 cassette decks by Industrial Engineer Alex Nikitin using Audio Tester software indicates that most will exhibit a flat response (that is, one with deviation above or below 3 decibels only below the graphical line) right up to 18 kHz – 20 kHz based on a -10dB recording level. Sony UX-Pro or TDK SA Chrome tapes were used by Alex.

On the Teac deck, the signal-to-noise ratio (even without noise reduction switched on) is excellent. Dolby B, the benchmark noise reduction for decoding pre-recorded cassettes, is included. Metal tapes can be played back but not recorded.

To sum up, the cassette mechanism has poor specifications relative to component hi-fi decks produced in the last twenty years. For example, the current Ion Tape 2 PC deck has far better specs for half the price. A better deck such as this could be plugged into the line-in inputs, but this seems like an unnecessary burden. Nonetheless, the response is superior to the average boombox. Audiophile Zomax (who evidently has great taste in music) maintains:

Tape playback was surprisingly good. Rush Chronicles and Nirvana’s Nevermind, both of which have been sitting around gathering dust for 15 years sounded crisp and surprisingly dynamic. It’s also great to be able to operate the tape playback using the remote.

A final word about recording

With respect to losing high frequency response when recording music using 128 kbps & 192 kbps MP3 bitrates or below-average grade cassette decks, Audiophile Goldear points out:

…Most material does not have such high-level [High Frequency] content. So, unless you are recording moog sythesizers which have a lot of HF energy, at high levels this really isn’t a problem (sic). Take a look at music on a spectrum analyser some time, and you will discover that the HF content above 10 kHz is usually 10 or 15 dB below the midrange in amplitude. So most of the time, you really don’t have that much of a problem.

Further information

Teac website. Full operating instructions can be downloaded.

American Ebay sellers. New stock is priced from $250 Australian dollars excluding air freight.

This entry was updated in August 2014. The article should not be construed as an endorsement of any particular device. Prospective buyers should carefully make their own enquiries. Now if we can persuade Teac for a test model? Pretty please…

Splitting WMA without inducing loss

WMA Snip is a lightning-fast programme written for the Windows XP operating system which will detect silence and reliably split large WMA files created by the Creative Zen V series recorders, pictured below. The cost of the software is roughly $19 AUD. A fully functional evaluation version which works for a fortnight can be downloaded so a prospective user can see if it is worth spending the dough. Users on Softpedia.com have given the software a rating of ‘fair’, comprising 2.7 stars. According to the developer, Andy Bridle:

For large files containing multiple tracks, WMA Snip can automatically define segments using silence detection; WMA Snip also connects to the online music metadata service at Music Brainz.org, and can use its data to locate tracks within long recordings and define these as segments…

The editing is non-destructive, in that the only changes made to the original file are the addition of file markers defining sub-sections of the file’s audio content, known in WMA Snip as segments; the audio content itself is not affected.

WMA Snip does not re-encode the music in the WMA files it detects and splits when Direct Copy for Saving Segment Audio Data is chosen. ‘The most accurate results are obtained with this method, in effect creating a digital copy of the segment’s audio data. The compressed, unprocessed audio data is copied to the resulting WMA file,’ according to Bridle’s documentation. Splitting of MP3 and Wave files is also supported.

A free alternative is to just split using Audacity. Please ensure you download the FFmpeg Import/Export Library which will enable one to import WMA files into Audacity. Please note that the official download site for this FFmeg Library is slow. Downloading from 4shared instead is recommended.

Audio editors such as Audacity (pictured) transcode or re-encode compressed audio such as WMA files. Audio splitters such as WMA Snip do not. Transcoding may exaggerate noisy digital artifacts. Enthusiasts at the Hydrogen Audio forum have compiled a guide to transcoding. Programmer & hotel disc jockey Andrew Davidson outlines his excellent tips to minimize the drawbacks. Whilst transcoding or re-encoding is undesirable, he writes:

Very often transcoding sounds fine. There is a slight quality loss, but for most non-audiophile purposes (e.g. casual listening) it will work out fine. In my experience, a well-encoded 192 Kbps or higher bitrate MP3 at 44.1KHz frequency can be brought down to 128 Kbps for listening in a car or other noisy environment, or using poor headphones in a portable MP3 player.

In this blogger’s own limited experience, there was no significant impairment of quality when transcoding from 192 Kbps to 320 Kbps constant bitrate MP3. However, there was less audible noise (presumably, a byproduct of transcoding) when transcoding the same MP3 192 Kbps material to the highly-rated Ogg Vorbis aoTuV, using quality setting 10. The side effects will invariably depend on the quality of the original source material, including the type of music.

Hi-fi recording: Creative Zen Neeon vs Samsung Yepp YP-T7

The final entry for this blog is a review of Hi-fi recording with two portable MP3 recorders, the Creative Zen Neeon and the Samsung Yepp YP-T7. The devices are examined from the perspectives of both an audio enthusiast and a long distance FM radio hobbyist. It’s a pleasure to share the joy of using these impressive devices to record audio.

Origin of manufacture

Yepp	Zen
China	Malaysia

Case material

Yepp	Zen
Aluminium	Plastic front, aluminium rear

Screen

Yepp	Zen
65,000 colours	Colour backlights

Storage device

Yepp	Zen
Flash drive	Mini Hard Disk drive

Battery life on playback

Yepp	Zen
10 hours	16 hours

User interface

Navigating the menus with the Yepp maybe difficult for those with big fingers. The larger Creative Zen Neeon is clearly easier to navigate the menus and find specific functions quickly.

Availability

Yepp recorders were expensive. This may explain why on the secondhand market, the recorders are in relatively scarce supply compared to the Creative Zen models. The results of a brief Ebay search seems to indicate that the Yepp series of recorders have maintained their value. A virtually identical predecessor to the YP-T7, the Samsung YP-MT6 256 MB is currently listed on Ebay for $65 Australian dollars. That is a competitive price for one of these models in a new, unopened condition.

Unattended timer recording

The Yepp can encode from line-in using the built-in Auto Sleep timer. If one wants to record for two hours, simply set Auto Sleep for 120 minutes, then hit record. When the time has elapsed, the recording will finalize and the device will switch off. This function is similar to the timers found on many cassette decks. According to the manual, the Yepp records to a maximum of 16 hours when connected to AC power or up to nine hours with the battery.

Recording quality

An entry level 256 megabyte Samsung YP-T7 model permits recording over two hours of MPEG2 Layer III (MP3) audio at the highest quality. The largest T7 Yepp has a capacity of one gigabyte. The bitrate is 192 kbps MP3 using the lauded Xing (Old) encoder. This encoder had its birth in 1999 and was consistently improved under ownership by Real Networks, according to the Hydrogenaudio Knowledgebase. Using headphones, no obvious digital artifacting, clipping or distortion was detected on recordings made from a commercially released music compilation.

The largest Creative Zen Neeon offers over six gigabytes of free space. Unfortunately, the Zen recording is performed at a bitrate of 160 kbps using the Plugger (Old) encoder. Newer Creative recorders such as the Zen V use the Windows Media 9 encoding which offers twice the compression of MP3. Plugger is a free MP3 encoder written by Alberto Demichelis in 1998. MP3 enthusiasts rate the sound quality of the encoder poorly in their listening tests. One user of the Neeon shares this observation:

Line in Encoding does sound alright, but it uses Plugger at 96, 128 or 160kbps, and at any bitrate [it is] not that great.

Recording level control

Neither device allows the line-in volume to be reduced. This seems unlikely to pose a problem the vast majority of the time. When using components that have an unusually high line level output (such as the Sony XDR-F1HD when tuned to highly modulated local stations) a line level attenuator may be needed to prevent clipping and distortion in the recording. The writers of the Samsung manual include this caution:

Adjust the volume of the external audio source to a suitable level and record it. If the volume level is too high, the [recorded] sound quality may be poor.

Splitting tracks

Both recorders allow the option to split files in the instance of a few seconds of silence during recording. Tested with a compilation, the Samsung recorder did not consistently split the tracks (even when set to a one second gap detection) whilst the Zen did.

Using software Audacity in combination with MP3Splt is one easy and effective way to split up a long MP3 recording. It is ideal for a recording made from an analogue source such as a cassette deck or turntable, where there is a three second gap between songs. Transfer the intact (unsplit) recording to a computer. Analyze the MP3 file in Audacity using the Silence Finder feature. This software enables one to export the split data so that MP3Splt can perform the split without any re-encoding causing loss of quality.

Additional software

MP3 encoder Plugger version 0.4 and the accompanying Plugger Shell version 1.3 can be downloaded from the Slovak Antivirus Center. Is it as terrible as the audiophiles suggest? Please comment!

EncSpot is a utility that will analyze MP3 files & rate the quality of the encoding used. For splitting, Audacity and Mp3Splt are highly recommended. Use these instructions. These free fully functional downloads comprise adandoned or open source software.

Further information

Review of recording with a Samsung Yepp by a DX enthusiast. Review of recording with a Samsung Yepp by a journalist. Review of recording with a Creative Zen by a programmer. Step-by-step instructions for line-in encoding from a CD player by Creative. Please be aware that these reviewers arenot using the specific models this blogger uses. Minor differences may apply. Line level attenuators cost $10 from Jaycar Electronics.

The text of article can be reproduced freely, provided you comply with the terms of the license. Simply attribute FMdxing.wordpress.com.

Editing compressed audio files

When editing audio from lossy formats, it is important to use a programme which does not re-encode the audio when saving your edited file. Re-encoding is also known as transcoding. It is like making a ‘copy of a copy’ and affects the quality. According to Wikipedia:

The process of lossy-to-lossy transcoding introduces varying degrees of generation loss… The key drawback of transcoding in lossy formats is decreased quality. Compression artifacts are cumulative, so transcoding causes a progressive loss of quality with each successive generation, known as digital generation loss. For this reason, transcoding is generally discouraged unless unavoidable.

The side effects are particularly problematic when re-encoding MP3 files, according to listening tests performed on the Hydrogen Audio forums. An enthusiast explains:

Each time, there was the same kind of distortion. It’s a form of ringing, very typical of lossy encoding, and which ruins the quality of background noise or ambiance. I was often amazed by the huge difference existing between the encoded file and the re-encoded one. I didn’t imagine that re-encoding could have such impact on quality.

Most programmes including Audacity & Total Recorder re-encode the audio! Whilst these are indispensable, it is recommended to use them to analyze your compressed audio only. This screen capture shows me doing the ‘dirty deed’, saving a purchased MP3 file using Audacity!

I don’t understand what programme I’m supposed to use! Explain it properly!

Sure. Here is a real example. I have a one hour recording of tropo recorded using my Degen DE1121 or Creative Zen which encode to 128 kbps MP3 and 160 kbps WMA compressed formats respectively. I connect the device to my USB drive and copy the file to the hard drive. I want to get rid of the static and keep the useful part of the file so I can share it on the blog.

Opening up the programme Audacity, I listen to the file using headphones and view the waveform to find out what bits are garbage (this step is optional). I make note of the only sections of the 60 minute recording that I want to keep. Let’s say I only want 01:30 to 6:45 and 15:00 to 24:15. Armed with these times, the actual editing of my MP3 clip performed in MP3 Direct Cut or MP3Splt. In the case of a WMA clip, editing is performed in WMA Splitter or ASF Tools.

Why should I bother with specific programmes for editing MP3/WMA files? Why can’t I just convert my compressed audio to a lossless format?

Is it true that you can simply convert the original WMA/MP3 clip to uncompressed Wave format and edit that file using Audacity. Unfortunately, this technique only avoids re-encoding if you never save it in a compressed format. Because uploading huge Wave files or lossless formats such as lossless WMA or FLAC is extremely painful for most people, I don’t consider this method really practical. You will still end up needing to convert the Wave file to a lossy format (re-encode) when you need to share it on the internet! However, this is an excellent technique for storing compressed audio on your hard drive. As long as you keep saving the file in Wave format only, this method will not induce any loss.

Do I need to worry about this if I record directly from my computer?

No. My understanding is that by recording directly to uncompressed Wave or lossless format, editing a file does not usually result in any loss of quality. If you are lucky enough to have your laptop’s sound card hooked up to your tuner to record, any editor will suffice. It’s not convenient for me to lug around my laptop every time I want to record. For this reason, I always utilize the convenience of recorders that induce some minuscule loss of audio quality (Compact cassette, Video cassette, DVD-RAM recording, DVD-RW recording & portable MP3/WMA recorders).

Free programmes to edit your Dolby Digital (AC3), MPEG2 Audio Layer 3 (MP3), Windows Media (WMA) or Ogg Vorbis (OGG) compressed audio recordings without re-encoding:

MP3 Direct Cut

Mp3splt for MP3 & OGG

WMA Splitter

ASF Tools for WMA

AC3 Splitter

This author has been professionally trained in live sound mixing. This includes recording experience (for broadcast) using early compression techniques such as Adaptive Transform Acoustic Coding (ATRAC). He has been using MP3 Direct Cut & MP3Splt for several years. Both programmes are extremely stable on an Intel Celeron 2 GHz laptop running Windows XP Home SP2 2002 edition. Asf Tools has been used successfully for several weeks. Feedback on the software cited (especially programmes that I haven’t fully tested yet) is greatly appreciated!

Everything Zen

No, this isn’t about an enjoyable Bush single release from the nineties. Definitely a more interesting topic, but sadly no. Also, the only thing I remember about Bush is that the vocalist married Gwen Stefani. Onto more pressing matters… Radio Geek has taken delivery of a Creative Labs Zen recorder. A cable and adapter are required to connect the unit to the rear RCA sockets of a component tuner, such as the Sony XDR-F1HD.

These particular models are from Jaycar. If a Jaycar Electronics store isn’t nearby, Dick Smith would probably have an equivalent. It’s worth mentioning that Jaycar is an Australian-owned private company. Unfortunately, they also sponsor the Bulldogs in the National Rugby League competition, but no-one is perfect! 🙂

3.5 mm stereo plug to 2 x RCA PLUGS

Available in various cable lengths

WA-7014
WA-7015
WA-7017

2.5 mm stereo plug to 3.5 mm stereo right angle SOCKET

PA-3502

or 2.5 mm stereo plug to 3.5 mm stereo SOCKET

PA-3532

Next time, there will be photos of the Creative Labs Zen Neeon recorder connected to the Blaupunkt Casablanca CD51 posted on this blog. In the meantime, this entry is hopefully better than nothing.

To connect the recorder to the Tecsun portable radio (or any FM or DAB+ portable) via the headphone socket, this cable only is required.

Lead 2.5 mm – 3.5 mm Stereo PLUG 1.5M

WA-7004