|
 |
|
|
Hi Fi Systems - part 2
By Barry Gardner of SafeandSound Mastering
In part one of this text we discussed acoustics which relate to the hi fi listening experience. We continue in part 2 with loudspeaker positioning, passive volume controllers and sound cards for the PC hi fi systems lover.
2)Speaker positioning is critical, it is suggested that loudspeakers are set up in front of your monitoring position to form an isosceles triangle with your head being the third corner of such a triangle. The tweeters of your loudspeakers (assuming they are bookshelf size) should ideally be at ear height. High quality speaker stands (with the speaker isolated with some neoprene pads) will also make a significant improvement to the fidelity of your hi fi experience. Speaker stands should be relatively resonance free which means there are no sympathetic vibrations to blur the imaging and tone of the music. See the example of an acoustic foam isolated stand in the picture resources below. 3)Passive volume controllers are a significant upgrade for those who have an integrated amplifier that has rear panel jumper access to the power amplifier section. Many hi fi amplifiers have jumpers (small connectors which bridge the RCA connectors between pre amplifier output and power amplifier input) these are located on the rear of the amplifier and route the signal from the pre amplifier into the power amplifier section. (You can see a photo of the power amplifier "main in" below) The pre amplifier allows you to use the source selectors such as CD player, Aux input, FM Tuner etc. They also include the circuitry for the bass and treble controls. If you are willing to bypass these facilities (for example if you listen only to your PC) then this upgrade will yield great sonic benefits in most hi fi systems with this type of amplifier. You need to purchase a passive volume controller this is simply a volume control in a box which does not include any active electronic components. There are a couple of suggested models. (please see links below) They do not need power and all they do is attenuate the signal that is received at it's input and pipe it to the output. In essence it is merely a volume knob. (with an audio input and an audio output) Ensure the amplifier is switched off for the next step.
The audio wiring is simple, you plug your source (such as CD player or sound card output) into the passive volume controller. (using relevant phono to jack adapters where required) and the output of the passive volume controller is plugged into the "power amplifier in". It is very important that you do this with the amplifier switched off. Please note that the input connectors of the power amplifier are set at maximum gain (like having the volume knob at maximum). So you must observe this simple power on, power off sequence. Switching on: source first (i.e. cd /PC), amplifier second.
Switching off : amplifier first, source second. This completely avoids any pops or clicks that could be damaging to loudspeakers. This will bypass the preamplifier electronics completely and you will have a more revealing, clearer, more natural and more detailed reproduction of sound. This is because you have bypassed a lot of potentially distortion and tone altering circuitry from the monitoring circuit. 4)The quality of a sound card and it's power source can make a difference in audio quality in almost all hi fi systems using a PC or Mac computer. The standard sound blaster card in a typical PC is a hive of noise, distortion and audio ills. However you can purchase very high quality sound cards which can make a dramatic improvement in audio fidelity. I will suggest a card as an example, not as an endorsement of the card itself but merely as an example to warrant further investigation for the reader. A card with very high audio specifications is the ASUS Xonar Essence STX. It has very low noise and very low distortion characteristics and will be a gargantuan improvement over a standard PC sound card. It is worth investigating the various USB2.0, Fire wire, PCI and PCI options. You can also look into professional studio products as there are some bargains in that area too. They are fairly easy to install and driver set up should be quite straight forward. Just check general operating system compatibility for your computer. 5)For the dedicated PC audiophile you may wish to consider the cleanliness of the power that your computer uses. This upgrade would be for the more technical person.Computer power supplies are not all the same, they will have differing specifications and some will be less tolerant of mains voltage stability and the overall quality can be widely variable. Purely as an example I use a power supply in my computer (used in the studio) which cost $160.00. It is a Seasonic X Series and has extremely stable power supply voltages which effects all of the computers components. Stable power means best possible performance of the sound card which will invariably be powered by the computers internal power supply. This model would be perfect for pc based hi fi systems but there are many good quality manufacturers to choose from. Avoid paying less than $100.00 for a high end PC power supply and stick to well known branded units. The internet can be a good place to find reviews on such products. 6)I was not going to mention mains filtering as most Western countries have stable supplies and are not prone to radio frequency interference. However I have recently found a very modestly priced product, approximately $40.00, which I can recommend trying if you have any radio frequency related problems with hi fi systems. (i.e. clicks through your speakers). I cannot guarantee it cures all mains related problems but I see it as a belt and braces approach for a clean and surge protected mains power supply. I have installed 2 of them in my mastering studio.It is called the Tacima CS929 6 way surge protected mains board. The boards contain surge protection should voltage spikes appear on the mains electric line and also radio frequency filters.You will have to search to find the product and see if it is manufactured for you local mains voltage and plug types. I am sure there are similar products by other manufacturers available locally if you cannot source one. It is my opinion that you should not spend more than $40-$50 dollars on such products. In countries subject to power cuts an uninterruptable power supply (UPS) is almost obligatory as such power cuts can damage PC equipment very easily, including data loss. (Electrical problems occur mainly when the power is re connected and surges can occur) So hopefully these tips will help improve your hi fi systems without breaking the bank, they offer real fidelity upgrades if you are willing to put in a little time and effort. Whilst I have tried to explain as clearly as possible how to approach these upgrades the user does so at their own risk. |
Passive volume controller example 1
| Passive volume controller example 2
 
Speaker stand example (with foam isolation)
Power amplifier main input photo (where jumpers reside)
PLEASE VISIT THE CONTRIBUTOR'S WEBSITE
music mastering
Website for online mastering at low rates
www.masteringmastering.co.uk/musicmastering.html
|
|
 |  | Dirk Bansch appreciated this intel. Feb 2, 2012 |  | | R Foreman recommended this intel. Feb 2, 2012 |  | | noline respected this intel. Feb 2, 2012 |  | | AmberLee liked this intel. Feb 2, 2012 |  | | odls appreciated this intel. Feb 2, 2012 |
Please login or sign up to rate this intel.
The copyright for this content entitled "Hi Fi Systems - part 2" has been specified by the contributor as:
All Rights Reserved
This content may not be copied, distributed or adapted by anyone under any circumstances.
|
|
May, 2012
2008
January, February, March, April, May, June, July, August, September, October, November, December
2009
January, February, March, April, May, June, July, August, September, October, November, December
2010
January, February, March, April, May, June, July, August, September, October, November, December
2011
January, February, March, April, May, June, July, August, September, October, November, December
2012
January, February, March, April, May
|
|
Not a member yet?
Qondio is a powerful network for making it online. If you have a website to
promote, we can help.
Sign up and get in on the action.
|
|
Welcome to Qondio! Discover the awesome power this network can deliver by going to our About page. Or you could skip straight to the Sign Up form.
|
|
