Evaluate different approaches to various sound sources and choose techniques and equipment appropriate to each circumstance.
The microphones being tested are of two types, Dynamic and Condenser. The condensers use phantom power of 48volts.
| Omnidirectional | Cardiod | Supercardiod |
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| Pick up patterns from all directions, used for good group vocals and grabbing ambient sound | The most common type of microphone and only picks sound from the front of the mic | A tight pickup pattern ideal when multiple mics are used. |
The pick-up pattern used is cardioid.
Harmonica Recording.
2a) I clapped to ascertain the room mode. Toms and symbols on the drum kit within the studio did give quite a lot of sound reflection. The kit was place at the back of the room.
a) Dynamic microphone Shure 58 microphone. b) Condenser Microphone AKG C414 microphone.
Initially the microphones were placed on channel 1 and 2 respectively but while recording it was decide that rather than trying to mimic the channels to simple swap the leads and place the condenser microphone into line 1.
Condenser microphones use phantom power and higher input levels are expected, but the harmonica is a naturally low output device, so peaking was not considered to become an eventually problem.
There were three types of playing to be assessed.
These styles can be broken down into two simple fundamental styles. Fast and Slow. With more precision you would consider, glissandos, octaves and other breathing techniques. Two pieces were used for the analysis. Ronda Alla Turca and Ashokan Farewell
The precision of the player allowed us to simple pan one performance to one channel left and the other performance to other channel right. This took place with Ronda Alla turca.
It was not appropriate to attempt similar panning with Ashokan Farewell because the piece is more emotive and slower in speed.
Some key features of harmonica playing to look for are, slide action, breathing (Jazz music Breathing can be desirable), and animated playing which will involve movement away from the microphone. The output of the harmonica is very different to other reed instruments when considering the point of origin of the sound. The sound in most reed instruments does come from the reed but its that sound in relation with everything involved with the instrument. The sound from the harmonica comes from just the reed.
Shure 58 microphone
Ashokan Farewell
The overall pick up of the microphone was good, but both the engineer and artist felt the sound was thin This observation was made in isolation.
Rondo Alla turca
The sound was clean and warm and gave me a strong impression that it could be placed in a mix down very easily. The sound had balance and natural sonic space, with the low end dropped of.
The extra sounds that are often desired to give the sound more character (clicking breathing etc) are omitted from the recording. Again there is a natural drop off in bass.
AKG C414 microphone
The pick up of this microphone is greater, the octaves are bright and there are a lot more extra tones because of the detailed nature pick up. The body of the sound is larger, with greater frequency pick up across the board. The sound can be described as warm, but extra bass and balanced frequencies made it seem compressed.
Initial the Shure 58 microphone appears to be a lot better, but careful consideration needs to be given to the intended purpose.
The Shure 58 microphone picks up less and has a balanced sound with good dynamics. The fact that it picks up less could lend itself to less atmosphere around the recording, if the instrument is to take the lead part. If you are performing live this is an ideal microphone. It gives the harmonica a natural sonic space while appearing to maintain the opportunity of good dynamics. The artist felt that the pick up pattern was not completely ideal because there did appear to be drops in volume, but if dynamics received from an animated performance is desired this microphone could be the one.
I believe that less post production is needed with this microphone but music would need to be shaped around this recording.
The AKG C414 microphone gives initial a less spectacular performance but because its pick up is greater a lot more ambience is received from the performance, but careful consideration needs to be considered to the piece being recorded with harmonica. There are a lot of artistic things that may take place in a piece note bending, glissandos, octaves as well as scale runs, the dynamics the artist may want to put on a piece. Animated play does not appear to be replicated in the recording either.
If the artist requires a true recording the AKG C414 microphone does win hands down, although the microphone may appear warm, flat and compressed, you will get a better reproduction on octaves and glissandos. However, the artist will have to work harder with dynamics. So you will only use this microphone and microphones of this type with the very best of players and you will need to be aware that animated play and dynamics of that nature may need to be inserted in post production. Condenser Microphones should only be used with the best musically artists.
Live choice is Shure 58 microphone. It gives the harmonica natural sonic space.
Studio choice is AKG C414 microphone but the artist needs to be good and know and understand the piece. This microphone will not cheat and make your performance better than it is, the Shure 58 microphone might by accident. The AKG appears to have more depth in its pick up pattern than the Shure 58 microphone. This can be deduced by animated play not resulting in noticeable or significant signal lose, with condenser microphones
Important Note
The harmonica being used is the Brazilian made Herring as opposed to the more popularly used Hohner. The sound reproduction of both these harmonicas is greatly different. The reeds rest on plastic with herrings and they rest on metal with hohners. This will lead to the hohner having a much more audible body of sound.
This allows for some seriously interesting possibilities when considering harmonica recording using condenser microphones and the variety of pick up patterns available.
The microphones being evaluated are Condenser and Dynamic.
Microphone Channel 1) Condenser AKG C451
Microphone Channel 2) Condenser Neuman U87.
Microphone Channel 3) Dynamic Shure 57.
Microphone Channel 4) Dynamic Internal Pick Up Microphone.
AKGC451
Appeared to have a good large range of pick up, this appeared to make the sound seem compressed with less dynamics in the piece. This microphone recordings allowed for the reproduction of harmonics of bass sounds. Giving the appears to be a warm bass filled sound.
Neuman U87
This seemed to provide the greatest amount of bass. The microphone specification suggests a smooth bass drop off. Again with this microphone the harmonics of the bass being produced dominant, leading to what I describe as a muffled, but warm sound.
Shure 57
The sound quality produced by this microphone appears to be more balanced and cleaner. Like the Shure 58 microphone, there is a natural sonic space associated with this microphone. The bass is tailed off with a slight drop in the bass harmonics frequencies as support to this drop.
Internal Pick Microphone.
The sound from this microphone has no body whatsoever. It appears to be very thin. The reason for this is explained in the evaluation.
Again for acoustic reproductions the Shure microphone appears to be the best, but this likely due to the instrument in use.
Although the pickup microphone was by far the worst it can not be assumed that this has taken place because of the quality of manufacture or the electronics in the microphone. When considering the location of the pick up microphone there will not be much development in the sound waves. This makes it an ideal microphone to get the signal for a processed reverb signal. This should give an opportunity to add ambience without an artificial sound being perceived.
The pick up from the Neuman is not suited to the guitar the frequency pick up is not flat enough where it would better be served to be flat, when considered with the bass tail off. The strikes are picked up but the bass drop of in isolation without bass harmonic drop off leads to the muffled sound, in my opinion.
As with the harmonica, the AKG represents the most stable and consistent recording possibility. When using this microphone the control of the sonic space and placement is placed in the producers hands. This control will allow the user to manipulate it into the background or make the sound the lead. The Shure microphones have a natural sonic space so mixing with them could lead to shaping tracks around these recordings.
Compare different audio recording systems and examine the techniques standards and approaches appropriate to each.
A comparison of current analogue and digital recording systems.
The analogue recording device will be a tape player.
The digital recording device will be a cd player and it will ultimately be the ADC and the DAC unit that will be under scrutiny.
Analogue recording devices use a plastic tape coated with magnetic particles. The tape moves across a magnetic recording head at a constant speed to record and playback. An "erase head", in the path of the tape, erases(re-aligns) the tape particles before the "record head". "two-head" devices have another head for recording/playback. In a "three-head" devices have one head dedicated to recording called a "sync head", and another for playback called the “repro head". Professional machines normally have three heads.
There are limits to what the particles can absorb and reproduce. The devices tape speed and bias affect the ability to record. If the device runs at a faster speed then more area is covered for a given signal (more particles are used to absorb the signal). Professional analogue multitrack recorders often run at 30 ips (inches per second). . The magnetic particles can reproduce high frequency sounds better. When a "Bias" when a bias of 100 KHz or so, much higher than human hearing, is used along with the recording
There is a lot that can go wrong with tape recording and the setting is important. Tapes may wrinkle, stretch and master recordings have to be accurate in the first place.
Mechanically this process is simpler and involves a lot of electronics. The input signal is sampled 1000's of times per second and each acoustic slice is given a digital number. The "analogue-to-digital converter" (ADC) receives the analogue input converting it into a stream of numbers and a "digital-to-analogue converter" (DAC) reverses the process.
The "sampling rate", determines how the sound will survive the digitization process. CD's are sampled at 44.1 K (44,100 times per second) which is the industry standard. Some formats offer 48 K sampling as well. DAC's and ADC's aren't created equally there are differences in how these machines sound, even though the theoretical consistency of 0's and 1's!
Digital tape machines use mechanical transports and plastic tape as a storage medium for the digital information. The Alesis ADAT and Tascam DA-88 are examples of new inexpensive digital multi-tracks. Hard disc recorders are another digital approach, many using computer software as controllers. E.g. Digi-Design and Soundscape machines. Examples of dedicated boxes you plug hard discs into for storage are the EMu Darwin, Vestax and Akai recorders
The size of the hard disc limits the amount of recording time. Locating and editing is easy. When combined with a computer as the interface, you have a powerful word processor for music.
2) The tascam 32 real to real was patched into the desk via the patch bay.
The analogue tape recordings had significantly more warmth than the digital recordings. It was as though dithering had taken place. There was an insertion of noise. The previous recorded signal was not completely removed from the tape! So some signal was multiplied into the recording. The prior recording on one of tapes was an ear training recording which was white noise across various frequency bands.
The digital recording device. The cd recordings were very crisp and clear. When consider with the microphones used from the previous section, the recordings appeared to mask the differences between the microphones. The differences however were still present.
The dynamic range of cd are larger than that of tape which allows for the clarity that is perceived.
The digital storage that is represented by the cd allows quick storage and easier manipulation.
The crispness and clarity lend itself to hip hop and RnB very well. Conversely tape recording could be used, greater than cd, for artistic effect in most other genres except jazz and classical music. For short term storage of masters CD’s are appropriate but with all new technologies it has become apart that CD’s are not appropriate for long term storage. Tape if stored carefully with consideration given to print through is proving to be the better medium for long term storage. This has been proven through the test of time. Accidents with tape machines has also led to some Digital effects that mimic these accidents for a lot of the music we make today, Flangers etc. Overall both have there place but the users have to take into consideration the artistic desires of required recording.
