Archive for the ‘Uncategorized’ category

guide to Audio Video furnishings

December 5th, 2022

You just sold you new plasma, lcd, DLP, flat panel television or projector. if you can’t find a proper vicinity to mount on wall or you need to house your audio video additives, you may most probably want an Audio cabinet for you additives, a television stand, or base to residence both the television and your own home theater additives. This guide will let you know all approximately audio video fixtures.Knockdown vs. AssembledMost home theater audio video furnishings both is KD (knockdown) or assembled in one piece. what is the distinction? KD way that the unit ships un-assembled in portions and you have to placed it collectively together with your time or rent someone to do it. The benefit of KD furniture is that it may normally deliver quickly for the ones humans that want to fulfill a time closing date. the opposite advantage it usually is much less luxurious than assembled furniture pleasant portions. The pleasant of KD gadgets varies greatly.  AV fixtures first and fundamental have to be able to take care of heavy televisions and additives and we trust that KD furnishings need to be made with MDF, not particle board. A time period related to KD (knockdown) is likewise RTA (ready to gather). those phrases suggest the equal factor. The client pays a touch much less, however has to place the item together on their time. the opposite small advantage to KD or RTA audio video furnishings is if it gets broken, replacement components can be sent to restoration the issue with ease. The first-class best furniture pieces have furnishings “styling” that’s made to be sen, not to be hidden in a closet. The hardware on these pieces are of higher pleasant inclusive of hinges and handles. maximum assembled fixtures is made with MDF with real wood veneers.Assembled furniture is a handy option for those with human beings with little time or staying power for assembling furnishings. The assembled choice in maximum instances is of better fine than most KD portions.. you would need to test the manufacturer because the market is flooded with many importers in which excellent can range and the packing of the furniture may be sub general for delivery on a freight truck.  All assembled furniture is inspected through our shipping centers prior to transport. This stage of exceptional manage does now not exist with many different on-line outlets. Who you purchase from is just as crucial as what you purchase in the global of on-line furniture stores. You should usually name the toll unfastened smartphone quantity of any web website before ordering assembled furniture. be sure to check the hours of the web site first before calling. the important thing consideration is sturdiness of the organisation. it is exceptional to ensure a organisation has been in enterprise as a minimum five years.don’t forget the placement of the house Theater FurnitureWhen making plans a domestic theater or media room, you will need to consider wherein to region your av rack. Will it’s hidden from view in a closet, a application room, a special av cabinet, or piece of fixtures. if you are hiding your furnishings in a cupboard or closet, don’t forget rotating AV racks which can pull out and rotate.if you plan to place the mount inside the front of your room, you’ll want to remember a cabinet that has fixtures styling, since it’ll continually be in view.If being located in the back of room or off to the side, you can recollect knockdown options.wooden or metallic GlassFurniture production can range.  In preferred, the look you need to obtain comes all the way down to timber or glass. If you like a traditional technique, wood AV furnishings may enchantment to you. maximum picks consist of black, cherry or very wellfinish. A maple or walnut end is available in positive patterns. if you select a extra modern look, you could recall a metallic glass aggregate. The glass is generally tempered to make it extraordinarily robust.Dimensions and Weight concerns for AV fixtures:The maximum common problem with choosing AV furniture is the scale. in case you are the use of for a tv stand you may need to find out the width of the tv, not the diagonal measurement. maximum manufacturers use diagonal measurements on television’s versus width measurements, you will want to find this specification to pick the best television stand length. the other commonplace measurement needed is interior shelf dimensions. that is very crucial when you have a few oversized av gadget, much less vital if you have everyday additives. last however now not least, don’t forget the burden of your tv and the load of your additives. The heaviest pieces are usually the television and the AV Receiver/Amp. most top shelf designs of our television stands can manage as much as 250lbs, but take a look at the specifications to make certain. the opposite attention is the indoors shelf load bearing. some amps can weigh as much as 100lbs! it’s nice to vicinity the amp on the lower shelf, that is fine for weight and sound absorption.lower back Panel OptionsMany video tv stands are popping out with again panel alternatives. A again panel permits you to mount a plasma or liquid crystal display tv on the panel and run the wires at the back of it. This makes for ease of set up and a price financial savings, because you don’t need an installer to run av cables or electric. A again panel is an appealing opportunity to mounting a plasma on a wall. A static fixed mount will possibly be the first-rate choice for a again panel. The again panel is also top because the tv is on the viewer’s eye level at the same time as sitting down.what’s in a name?Many humans look for equipment racks the usage of these phrases: Audio rack, video rack, av rack, audio furnishings, av fixtures, tv stand, television stand or home enjoyment middle. generally, a “rack” is knockdown and “fixtures” is normally an assembled piece. make sure to test the details on all merchandise. A name will be just a identify that does not appropriately describe the piece you’re ordering.LongevityHow long do I need this piece of furnishings to closing? How lengthy will I be living in present day house? if you are making plans on transferring to a brand new place, you may recall a brief solution as opposed to a greater permanent furnishings buy. The “Knockdown” alternative is right if you are going to transport in a pair years. if you plan on living for your modern-day residence longer than five years you may remember an assembled av furniture buy.

Explaining Forensic Audio – Part 1

November 13th, 2022

Forensic audio includes a number of different areas of expertise. The four main ones are audio enhancement, audio authentication, forensic transcription, and speaker identification. Part one of this article explores enhancement and authentication.

The concept of forensic audio investigation may have become popular in recent years along with the forensic sciences in general but it’s been in practice since World War II. With audio use in full swing for radio transmissions across long distances,Guest Posting scientists were trying to identify the voices of their enemies among the many radio broadcasts that took place on open frequencies. The work done in forensic audio investigation today is based on the pioneer work of those scientists.

Specifically, forensic audio has to do with any type of audio of an evidentiary nature. In modern cases, law enforcement or other legal professionals (e.g., defense attorneys and prosecutors) will turn to a forensic audio examiner to perform any one of a number of services where audio is concerned.

In many cases these specialists are hired on a contract basis.

While the most common Hollywood portrayal is audio enhancement with a few twists of a knob (if only it were so easy) there is a great deal of work that can be done:

Audio Enhancement – the most common and offered by just about every forensic audio company you can find.
Audio Authentication – geared toward tape and digital formats
Forensic Transcription
Speaker Identification
There are also a number of other services or procedures that can be classified in their own right as a specialty process or “miscellaneous” in terms of categorization. This article will focus specifically on Audio Enhancement and Authentication.

Audio Enhancement
Audio enhancement is the most common and well known service where forensic audio is concerned.

It’s not likely that one can take a garbled and mangled inaudible conversation and “tweak it” to produce clear speech that is intelligible. While audio enhancement isn’t specifically focused on speech, that is usually the intent behind cleaning up or enhancing audio for legal purposes. It’s a means of reducing or filtering out unwanted noise from a poor recording in order to clear up the speech that’s covered with noise or is a victim of poor recording methods.

A forensic examiner is not a miracle worker however, and while modern software and equipment has provided a variety of tools to improve the quality of speech in a recording, there are still limitations. When it comes to enhancing speech, you can’t fix something that’s just not there. If the recording doesn’t contain the robust elements of someone’s speech, and the equipment only picked up bits of a word or phrase, there is no magic software to fill in the blanks. Enhancement techniques can sometimes have fantastic results with intelligibility, but more often would be a disappointment to the layperson.

In terms of speech enhancement, an examiner can offer critical listening in combination with forensic transcription and speech decoding methods to help identify and discern what is being said. Again, technology can only do so much so an examiner with linguistics and phonetics experience is usually best for the job. However, if the speech waveform isn’t picked up by the recording device or is masked by noises of the same frequency range, he won’t be able to decipher the speech.

Forensic audio enhancement sometimes simply involves increasing the volume of a whisper from a suspect where traditional playback – even at high volume – can’t help an individual understand the utterance. Audio enhancement offers the most benefit in situations where noise can be eliminated or at least reduced so as not to distract the listener from the speech. Enhancement techniques are quite good at getting rid of electronic buzzing or hum and other noises such as tape hiss, the crackles and pops of a phonograph record or the beeping of a backing truck, open car door, low battery warning of a fire detector, etc. Enhancement used in this way is often called improving the listenability of the recording. Unintelligible speech isn’t made intelligible but the recording is easier on the ears.

Audio Authentication
Authenticity is an important part of legal matters where evidence is concerned. This is especially true when it comes to audio that is or will be entered into evidence in a criminal or civil matter. As technology advances, it becomes progressively easier for an individual to tamper with a recording.

Audio authentication – either involving tape authentication or digital file authentication – is a way to ensure that the audio being utilized as evidence has not been tampered with in some way.

Not only will a forensic audio examiner use software to examine the actual recording, but authentication involves examining the physical tape itself and its casing.

This includes:

Checking the tape for splices
Examining the tape’s plastic shell to check for prying or disassembly
A process of examining the tape call magnetic development
Magnetic development involves using a magnetic liquid called ferrofluid in the examination of audio or video tape. The ferrofluid allows the forensic examiner to see the magnetic patterns on a tape. The types of things the audio engineer would look for include magnetic signatures left by stopping, pausing and starting the recording process. It can also be possible to tell if the tape has been recorded over or simply erased and left blank.

Newer software provides an edge when it comes to detecting authenticity in audio as it looks into variances that could lead to falsification of a recording – particular in tape recordings:

Equipment noise – hums, pops, varying pitch in inconsistent forms over the whole of the recording
Fading – Any gradual or sudden decline in volume that effects the interpretation of noise or dialogue. If the sound cuts out completely that becomes a gap in the recording
Gaps – Any segment where there is a change (often unexplained) in the content or context of an audio recording. A perfect example of this is the infamous Watergate recording where there is an 18 and ½ minute gap in the recorded audio that was later discovered to be an overlaid recording of electrical interference.
Transients – These are clicks or pops and other “attack” sounds within a recording and may signify that there has been a splice or some other alteration to the recording
There are a number of methods that are used to authenticate a recording, checking it specifically for originality. An obvious and important tool that a forensic audio examiner has is the ear. Critical listening affords a great deal of benefit and it takes training and experience to know what to listen for while playing a track over and over.

In some cases, an examiner may have to run through a section of audio many dozens of times. They examine bits of a conversation or sections of a recording to fully understand the sounds – including both foreground and background sounds. If something stands out the examiner will further investigate that specific segment using their trained ear to discern if the recorded event is authentic or not.

Beyond listening, the examiner utilizes physical inspection as well as spectrum and waveform analysis to visually inspect the quality and construct of a specific piece of audio. All of these methods come together allowing the examiner to certify the authenticity of a tape recording.

Things become more difficult when a recording is made using a digital recorder that creates audio files such as .wav or .mp3. While many of the above methods may be useful with a recording that originated as a digital file, it is somewhat easy for a knowledgeable person to edit the file without leaving any known sign of doing so.

One promising method of digital authentication is the use of ENF (electric network frequency) data. Whenever someone is recording while plugged into an electrical outlet or using a battery operated device within an ENF magnetic field, their recording will include a 50Hz or 60Hz (depending on country) waveform signature. This signature can be compared to an ENF database to possibly determine where and when the recording was made, whether it’s an original or a copy, or whether it was edited or altered in anyway. Digital audio authenticity examination, and more specifically the use of ENF, is in its infancy and has a way to go before forensic audio examiners reach the level of sophistication that has been achieved with authentication of analog tape recordings.

The use of software to determine authenticity and enhance audio is just the beginning when it comes to forensic audio. Depending on the situation, additional specialty services or skills may need to be applied such as speaker identification and the analysis of gunshot sounds to determine if more than one weapon was used, which type of firearm was used, or the sequence of the shots fired. Forensic audio is a robust trade that encompasses a number of specialists who work together to bring clarity through the study and examination of audio.