Frequently Asked Questions...  Please select from the list below frequently asked questions by online customers.     1. CDR80 Discs - will they work in my machine? 2. Compressors - how do they work? 3. Thread Sizes - what is the standard thread size for a mic stand? 4. DI Boxes - what is a DI Box for? 5. Power Ratings - Matching up amplifiers and speakers? 6. Equalisation - how do the different types of EQ work? 7. MIDI - what is it and how does it work? 8. Cable - which type do I need? 9. Surge Protection - why do I need to use mains filters? 10. Rack Heights - what is a U (as in 2U, 3U etc)? 11. Normalising - what's that all about, then? 12. Soundproofing or Sound Treatment - what's the difference? 13. Acoustic Tiles - what advantages do they give you? 14. Price Match - what does the Studiospares Price Match promise mean? 15. Quick Ordering - how does it work?

1. CDR80 Discs BACK TO TOP   Q. CDR80 Discs - will they work in my machine? A. 74 minutes or 650MB is the Orange Book CD standard. This guarantees that CD drives and Media are compatible. Earlier CDR74 drives will not recognize the new 80 minute length and will still either use only 74 minutes/650MB, or wil reject the disc. Drives showing known problems are Sony CRX100, HP8100, and Philips CDD3610. These problems do not affect domestic audio CD recorders (the ones requiring the more expensive SCMS-encoded discs).

2. Compressors BACK TO TOP   Q. Compressors - how do they work? A. Think of a compressor as an automatic fader control- its purpose is to reduce peaks or rapid transient levels in your input/output signal or your recorded material and so keep the dynamics of a signal under control. Using either solid-state circuitry or valves the compressor will allow you to decide: (1) how much the signal level is reduced in relation to the input level, known as the ratio or slope; (2) at what level of gain the reduction will begin, known as threshold; (3) how quickly the gain reduction is applied, known as attack; (4) how quickly the compression is removed once the signal has droppped below the threshold, known as release; and (5) in some cases the type of compression you want to use- 'hard-knee' for a fixed compression ratio regardless of gain, or 'soft-knee', sometimes called 'over-easy', where a higher ratio is automatically applied to higher level signals and vice-versa. Use in conjunction with your console's insert points, and insert or send/return cables, on individual tracks, drums, or whole mixes. Try a valve compressor to give that extra body and warmth to vocals, or connect an equalizer to the side-chain input if you only want to compress particular frequencies.

3. Thread Sizes BACK TO TOP   Q. Thread Sizes - what is the standard thread size for a mic stand? A. Unless otherwise stated in the product text, Studiospares have standardised on 3/8inch threads on all stands, mic holders, booms, clamps, and accessories. Various Thread Adaptors are available if required.

4. DI Boxes BACK TO TOP   Q. DI Boxes - what is a DI Box for? A. A Direct Injection box, or D.I. contains a circuit or transformer which is used to convert a high level, high impedance signal from an instrument such as a guitar into a low impedance signal, allowing you to connect that instrument directly to your mixing console mic input, and to use longer cables with less noise. Most will also incorporate a ground lift switch. This means you can reduce the hum caused when two pieces of equipment are connected to ground via more than one path. Passive boxes' transformers are not powered; active boxes use a battery or the mains to drive the circuits . Use between the instrument and the console's input stage, and combine D.I.'d signal with the signal from your miked-up cabinet for that 'clean but fat' guitar sound!

5. Power Ratings BACK TO TOP   Q. Power Ratings - Matching up amplifiers and speakers? A. One of the causes of speaker damage is the use of an underpowered amplifier. The simplest way to match speaker & amp is to: Find out the RMS wattage rating and Impedance (mostly 8 Ohms) of your speaker. Look for an amplifier that matches those figures, and allow an additional 15 to 20% extra wattage for headroom. Remember that "Bass definition" and speaker efficiency requires adequate amplifier power. For additional advice ask our Sales Department.

6. Equalisation BACK TO TOP   Q. Equalisation - how do the different types of EQ work? A. A parametric equalizer is one that uses variable or ³sweepable² frequency controls to allow you to choose which frequency you want to cut or boost. Characterised by knobs rather than sliders, a parametric EQ will sometimes use a Q control- this is simply a rotary pot with which you adjust the breadth (bandwidth) of the cut/boost frequency; wider Q will apply a sloping amount of effect to the chosen band as well as those around it, whereas a tighter Q homes in only on the selected frequency, isolating it for you to reduce in level or increase. Overlapping frequency bands are also common, allowing greater flexibility. Almost all professional and semi-professional mixing desks will have a form of parametric EQ incorporated in their channel strips. Graphic equalizers are commonly characterized by sliders on the fascia, split into 5, 7, 10, 15, 31 or even 33 frequency bands of cut or boost. They can be helpful if you require a visual representation of the EQ curve, or if you need to have rapid access to fixed areas of the spectrum. You can classify an equalizer by the shape of its response; a low-pass filter will heavily attenuate above its cut off point. Shelving EQ produces a shelf above which the boost is constant while peak EQ¹s characteristic shape is...yes, you¹ve guessed it, a hill-shaped peak. Used properly, EQ will add clarity to your mixes by subtly enhancing the best and disguising the unwanted parts of each instrument¹s spectrum; correctively it can smooth out harshness or add missing sparkle; and used creatively there are no limits to what can be achieved.

7. MIDI BACK TO TOP   Q. MIDI - what is it and how does it work? A. MIDI- Musical Instrument Digital Interface- is essentially a language which compatible devices use to exchange data. It allows one unit, a computer based sequencer for instance, to tell another, let¹s say a MIDI equipped keyboard, what notes to play and when, for how long and even how loud to play them. It can be used to tell devices which sounds to play for each sequencer part (i.e. drums, bass, strings), to synchronise live instruments recorded onto tape with programmed ones, and/or to remotely access sounds on other MIDI instruments from a single source. A MIDI equipped digital mixer may be able to record and playback fader moves, mutes and precise location info. MIDI channels are numbered 1-16 with each channel capable of transferring separate information. A MIDI signal is carried between units via 3pin or 5pin DIN cables. IT IS NOT AN AUDIO SIGNAL!! When you record MIDI data from your keyboard into your sequencer and you play it back what you are hearing isn¹t the audio recorded and replayed, as on a multitrack recorder. It is the sequencer sending note on note off MIDI data back to your keyboard and triggering its voice in real time. This means you can actually preview other sounds playing the same phrases, edit single notes, change key or tempo and add or reduce velocity to one or several notes without compromising the original performance or having to repeat it! MIDI Time Code (MTC) and MIDI Clock (MIDI CLK) will tell the various devices where they are within a particular piece of music, allowing you to control and synchronise them all from a master machine. If you have more than one keyboard or module, or you have a multi-timbral keyboard, you can use MIDI to access up to 16 parts or voices simultaneously for each device, without committing anything to tape. MIDI In, Out & Thru ports on these units mean they can be connected together in many configurations, according to your specific needs. For more advice on the best ways to utilise MIDI in your studio consult the Studiospares sales team or visit our sales desk.

8. Cable BACK TO TOP   Q. Cable - which type do I need? A. PATCH LEADS For Quarter inch plugs Unbalanced. (Unsymmetrical) Use single core screened cable from the following:- Europa Installation cable, Klotz Installation cable or Sommer Session. Balanced. Use two core screened cable from the following types:- Europa or Klotz, or Sommer Club. PATCH LEADS For Bantam plugs Klotz Bantam Patch Cable with its enhanced screening or Sommer Goblin Patch Cable. Both can be screwed into the threaded barrel of a Bantam Plug. INSTRUMENT or GUITAR CABLE Europa OFC (leave one wire disconnected), Klotz Guitar Cable or Sommer Spirit Instrument cable. All these are flexible, will not easily break and have good screening properties. MICROPHONE LEADS Europa OFC or Klotz Mic Cable, or Sommer Club, Source or Syntax. If RFI/Thyristor lighting is around use Starquad. STUDIO WIRING For individual cables For unbalanced systems with individual plugs and sockets use any of the following jacketed cables:- Economy Lightweight, Budget unbalanced, Klotz installation, or Sommer Session. (Note. It is often cheaper to use two core cable and leave one wire a disconnected). For balanced systems using plugs and sockets use our General Purpose cable, Europa OFC, Klotz, or Starquad Use FS1x foil screened if cable is rarely moved. STUDIO WIRING For multiway cables Studiospares foil screened FS8x, Studiospares jacketed or Sommer Mistral or Sommer Planet. If plugs have to be wired to unjacketed foil screened multiway cables slide heatshrink over exposed foil to act as a grip/strain relief and to stop foil slowly unwinding. CABLE SNAKES Providing cable is not going to be abused or wound round radiuses less than 10cm, use Jacketed foil screened cable where leads will be terminated by individual XLRs or Jacks. Where both ends are wired to either a patch bay, stage wall box or multiway plug use unjacketed multicore because inner jackets make the overall diameter too great to fit into a multiway connector. Use Studiospares or Sommer Planet cable

9. Surge Protection