Welcome to No Limit Sound Productions

Company Founded
2005
Overview

Our services include Sound Engineering, Audio Post-Production, System Upgrades and Equipment Consulting.
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Our mission is to provide excellent quality and service to our customers. We do customized service.

Saturday, November 18, 2017

Q. Can I improve my monitors’ frequency response with EQ?

I use a set of Roland DS50 monitors. According to the graph in the manual, the frequency response isn't what one would call completely flat. Would it be reasonable to plot the discrepancies and compensate for them by adjusting the respective frequencies with EQ? Or would I then be fooling myself?

Via SOS web site

SOS Technical Editor Hugh Robjohns replies: This frequency response is perfectly normal, and I'd be extremely suspicious if I saw a completely flat line. There are lots of reasons for these response irregularities, including cabinet effects, such as internal reflections, external diffraction and port resonances, driver response inconsistencies, crossover effects and matching, and so on. However, providing the response variations are modest and gentle (and the quoted +/-3dB spec is, again, normal and reasonable) there won't be any problems. The effect of the room and its contents on the speakers' responses at low frequencies and through the mid-range will be orders of magnitude larger than any built-in variations anyway.

Plotting the discrepancies and using EQ to adjust the respective frequencies is a nice idea, and many people have tried it over the decades, but the situation is more complex than simple EQ can resolve, and the inherent phase shifts involved in conventional analogue EQ often make the problem worse rather than better.
As conventional analogue EQ isn't really precise enough, several speaker manufacturers have used DSP techniques to try to correct for speaker response anomalies, but I'm not convinced there is any real benefit. Well-designed speakers using high-quality components rarely need this kind of correction, and applying it to budget speakers is a bit like putting a sticking plaster on a major knife wound; it doesn't fix the underlying problems.

There are also many digital room‑acoustics correction devices on the market that attempt to address the in-room performance of a speaker system by levelling the response (amongst other things), but while they often make a difference, I feel the traditional acoustic treatment approach provides generally better and more consistent results.

 The idea of trying to use EQ to compensate for perceived shortcomings in the frequency response of your monitors might seem tempting, but it can actually make things worse. Addressing your mixing room instead, using correctly placed acoustic treatment, will usually yield much more sensible and consistent improvements.  
The idea of trying to use EQ to compensate for perceived shortcomings in the frequency response of your monitors might seem tempting, but it can actually make things worse. Addressing your mixing room instead, using correctly placed acoustic treatment, will usually yield much more sensible and consistent improvements.

In conclusion, I would not recommend trying to apply inverse EQ to your monitor chain, as it's likely to make things worse rather than better. The frequency response of the speakers you have is adequately flat for a design of this type. You will gain a far greater improvement in sound quality by addressing the acoustics of your listening environment, treating the mirror points with broadband absorbers and installing bass traps to control the room modes.



Published July 2011

Korg Kaoss DJ - Control Your Mix (Free Serato DJ Intro Download)

Friday, November 17, 2017

Cory Henry Invites You To The 2015 Korg Pre-NAMM Show

Q. Does my shotgun mic have any uses in the studio?

I've recently inherited a shotgun mic that seems to be in pretty good condition. However, I never do any kind of video or broadcast work, so I can't see myself using it for its intended purpose. I'm loath to get rid of something if I can make use of it, so are there any uses for a shotgun mic in the studio?

James Gately, via email

SOS Technical Editor Hugh Robjohns replies: You can always find a use for a decent mic in a studio, but shotgun — or rifle — mics aren't the easiest to use because their particular blend of properties don't really work well in enclosed spaces.

The shotgun mic gets its name from the long slotted tube — the 'interference tube' — affixed in front of a (usually) hypercardioid capsule. The idea of the tube is to enhance the rejection of off‑axis sound sources, and thus make the polar pattern more directional, although it relies on on‑axis sounds not being picked up off‑axis (and vice versa), and that means it doesn't work so well in an enclosed and reverberant space.
Though a shotgun mic may appear to have obvious uses in the studio — rejecting, as it does, off‑axis sound effectively — it actually captures highly coloured spill and is, therefore, very difficult to use in the studio context. 
Though a shotgun mic may appear to have obvious uses in the studio — rejecting, as it does, off‑axis sound effectively — it actually captures highly coloured spill and is, therefore, very difficult to use in the studio context.

In normal use, the sound wavefront from an on‑axis source travels down the length of the tube unheeded, to strike the capsule diaphragm in the usual way, and so generates the expected output. However, sound wavefronts from an off‑axis sound source enter the tube through the side slots. The numerous different path lengths from each slot to the capsule itself mean that multiple off‑axis sound waves actually arrive at the diaphragm at the same time and with a multitude of different relative phase shifts. Consequently, this multiplicity of sound waves partially cancel one another out, and so sound sources to the sides of the microphone are attenuated relative to those directly in front. The polar pattern essentially becomes elongated and narrower in the forward axis, and the microphone is said to have more 'reach' or 'suck'.

Sadly, though, there's no such thing as a free lunch, and in this case the down side is that the interference‑tube phase cancellation varies dramatically with frequency (because the phase‑cancellation effects relate to signal wavelength as a proportion of the interference‑tube slot distances). If you examine the polar plot at different frequencies of a real interference‑tube microphone, you'll see that it resembles a squashed spider: deep nulls and sharp peaks in the polar pattern appear all around the sides and rear of the mic. What this means, in practice, is that off‑axis sounds are captured with a great deal of frequency coloration, and if they move relative to the mic, they will be heard with a distinctly phasey quality.

So while it might seem that a shotgun mic could afford greater separation in a studio context, in reality the severe off‑axis colouration makes the benefit rather less advantageous, the strongly coloured spill doing more damage than good and making it almost impossible to get a sweet‑sounding mix.

Shotgun mics really only provide useful advantage out of doors (or in very large and well‑damped enclosed spaces), and where no other, better‑sounding alternative is viable. My advice would be to sell the mic to someone who is involved with film, video or external sound effects work, and use the funds to buy something more useful for your studio applications!



Published August 2011

Thursday, November 16, 2017

Intel Processing; Seagate Storage

By Martin Walker
Computing's big names continue to offer more power in less space, as Intel pioneer new microprocessor technology and Seagate put even more data storage on your platter...
Coming soon to a PC near you — Intel's Ivy Bridge processors will offer faster performance and greater efficiency, thanks to a radically new 3D transistor design. On the left is the 32nm planar transistor in which the current (represented by the yellow dots) flows in a plane underneath the gate. On the right is the 22nm 3D Tri‑Gate transistor with current flowing on three sides of a vertical fin. 
Coming soon to a PC near you — Intel's Ivy Bridge processors will offer faster performance and greater efficiency, thanks to a radically new 3D transistor design. On the left is the 32nm planar transistor in which the current (represented by the yellow dots) flows in a plane underneath the gate. On the right is the 22nm 3D Tri‑Gate transistor with current flowing on three sides of a vertical fin.

The next generation of microprocessors from Intel in the Sandy Bridge series is code‑named Ivy Bridge, and will be introduced sometime in 2012, when Intel move to an even smaller 22nm manufacturing process. However, the microprocessors are notable for another reason: they will use the world's first 3D transistors. In place of the two‑dimensional planar (flat) transistors of the past with a single 'gate' on top, 'Tri‑Gate' transistors feature incredibly thin three‑dimensional silicon fins that rise up vertically, with a gate on both sides of the fin and a third on top.

The main advantage is that since the fins are vertical, transistors can be packed even closer together. This, in turn, should help extend Moore's Law, the 1965 theory by Intel co‑founder Gordon Moore that the number of transistors in a given area would double every two years, with increased functionality and reduced cost. Another advantage of the Tri‑Gate technology is that it allows more powerful processing with greater efficiency: the new transistors are said to consume half the power of current ones for the same performance, and up to a 37 percent improvement at low voltages compared with current planar transistors.

Other new features for Ivy Bridge include integral USB 3 and Thunderbolt support, which should reduce compatibility problems for musicians (compared with the current situation of motherboard manufacturers having to add their own support chips), as well as upgrades to the graphics core, which should help those involved in video work.

Nebula Kernels Promoted

Back in SOS February 2008 (/sos/feb08/articles/nebula3.htm), I reviewed Acustica Audio's Nebula 3, an impressive 'dynamic convolution' plug‑in with great potential, although at the time the bundled effect‑library patches varied greatly in audio quality. The secret of Nebula's engine was 'Volterra Kernels', each of which is essentially a stream of treated audio chunks that acts rather like a single convolution impulse response, but which can exist in various tiers.

Nebula 3 now offers a new 'Aqua' interface to third‑party developers, providing the same 'dynamic convolution' engine but giving them free rein with GUI design. As this 'vintage British console channel strip' plug‑in from CDSoundMaster shows, you may even be using the Nebula 3 engine without realising it. 
Nebula 3 now offers a new 'Aqua' interface to third‑party developers, providing the same 'dynamic convolution' engine but giving them free rein with GUI design. As this 'vintage British console channel strip' plug‑in from CDSoundMaster shows, you may even be using the Nebula 3 engine without realising it.

The output stream morphs between these tiers, depending on the desired effect, so, for example, Nebula can model compression by moving between the tiers depending on input level, at a speed determined by the attack/release controls, and at a depth determined by its threshold control. A Nebula preamp does the same at maximum speed to vary the level of harmonic distortion/saturation with input level, and swept filters and phasing or flanging can be reproduced by smoothly moving between the tiers using one of Nebula's LFOs.

Over the last three years, Acustica's tiny part‑time development team have concentrated on what they do best — enhancing the Nebula engine so it can capture and replay the sounds of existing hardware with greater realism and efficiency. However, Nebula's interface can still be confusing, and while it comes with a utility for capturing kernels, that's not a job for the faint‑hearted, either.

Raising The Bar

Fortunately, third‑party developers have stepped up to the plate, releasing a host of Nebula libraries that are streets ahead of the bundled offerings in both realism and versatility, in the process capturing vintage hardware EQs, compressors, tape saturation, tube preamps and consoles, as well as plenty of other exotica. Many are at pocket‑money prices, while others audibly rival or arguably surpass much more expensive plug‑ins!

I'm hoping to explore the best of these shortly, but in the meantime Nebula 3 Pro users can point their browsers at the new and improved Acustica Audio web site (www.acustica‑audio.com) to catch up with all the improvements, and at www.alessandroboschi.eu, www.analoginthebox.com, http://cdsoundmaster.com, http://cupwise.com and http://rhythminmind.net to see what some of these third‑party developers have been up to.

PC News

Windows 7 On The Up: Microsoft have sold 350 million licenses for their Windows 7 operating system in the 18 months since its release, and also estimate that 90 percent of corporations are currently in the process of migrating to Windows 7. This is a huge improvement compared with the take‑up of Vista, but hardly surprising, given the latter's failings. Ironically, though, Windows XP (which celebrates its 10th birthday in October 2011) still remains in pole position worldwide, holding 54 percent of the global market, although Windows 7 is expected to have caught up in a year or so, by which time Windows 8 could be upon us. Interestingly, Windows 8 will finally see the end of the dreaded 'blue screen of death' crash message — it's going to be black instead!

Seagate Break 1TB Barrier: As I write this, Seagate have just launched the first commercially available 3.5‑inch external hard drive to offer one terabyte per platter — the highest storage capacity on the market to date. Seagate's GoFlex Desk range offers models with capacities up to a massive 3TB of storage spread across three platters, and by the time you read this, its flagship Barracuda desktop hard drives may also be shipping with this technology on board.


Published July 2011

Wednesday, November 15, 2017

Korg Step Master: Function

Q. How should I use my new multi‑pattern microphone?

Having been using a cardioid mic for some time, I've just bought an Audio‑Technica AT2050. Although my decision was partly based on the flexibility of its switchable polar patterns, I've not ventured beyond the cardioid pattern that I'm used to since I bought it. How can I use the different patterns? Are there any creative techniques I can use?

Ben Allen via email

SOS Reviews Editor Matt Houghton replies: This is probably a rather broader topic than you realise, but it's great that you're showing curiosity and a willingness to learn! Generally speaking, the best thing to do is to learn through trial and error: try out the different patterns and compare the results. Even with all the theory in the world, you need to make errors in order to learn! That said, we've published several features over the years that discuss this topic in more detail (for example, there's one in SOS March 2007: /sos/mar07/articles/micpatterns.htm), and I'd suggest that you have a read of some of those.

To get you started, though, I'd recommend investigating the figure‑of‑eight pattern, which is really useful where you want to reject sounds off to the side: you point the null at the bit you want to reject, and the front (or rear!) at the bit you want to capture. Bear in mind that the trade‑off in achieving this excellent off‑axis rejection is that you pick up as much sound from the rear as you do from the front, so you either need to be working in a nice‑sounding room, and be happy to capture ambience, or to have some sort of acoustic shield placed behind it. I find that figure‑of‑eight mics often make very useful room mics: you'd set them up to pick up room ambience only, with the null pointing toward the sound source.

A multi‑pattern mic, like the Audio‑Technica AT2050 shown here, provides a relatively inexpensive way to try out different polar patterns. If you already have a cardioid mic, you could use the two in conjunction to start experimenting with stereo miking techniques. 
A multi‑pattern mic, like the Audio‑Technica AT2050 shown here, provides a relatively inexpensive way to try out different polar patterns. If you already have a cardioid mic, you could use the two in conjunction to start experimenting with stereo miking techniques.

If you have another cardioid mic handy, you could try Mid/Side stereo recording, with the cardioid mic (it could actually be an omni, figure of eight or anything in between, but cardioid is more typically used) pointing toward the sound source and the figure-of-eight rejecting the sound source but picking up from left and right. In this instance you record three tracks: the cardioid, and two signals from the figure of eight. Polarity‑invert (ie. flip the 'phase') one of those figure‑of‑eight signals, and route both to a group channel in your DAW, and you have a mono‑compatible stereo recording whose width you can alter by balancing the cardioid's fader with the figure‑of‑eight group fader. If this whistle‑stop explanation is a bit brief, you can learn more about the technique at /sos/feb02/articles/cheshire0202.asp.

The polar patterns available from most multi‑pattern microphones include the three shown here: (left to right) cardioid, omnidirectional and figure of eight. The diagram shows where the polar pattern picks up sound and where it rejects it. 
The polar patterns available from most multi‑pattern microphones include the three shown here: (left to right) cardioid, omnidirectional and figure of eight. The diagram shows where the polar pattern picks up sound and where it rejects it.

The omnidirectional pattern is also potentially very useful. As this is a large‑diaphragm mic, it's probably not as true an omni pattern as you'd find in a small‑diaphragm capsule, but it should give you a much more 'honest' sound than you'd get from the cardioid pattern, so if you're looking to capture the sound you hear in the room, an omni is a good bet. Beware again, though, that this pattern picks up sound from all directions. That makes it great for one‑track‑at‑a‑time recordings (it's a good bet for acoustic guitar, for example), but you need to be in a nice‑sounding space — not too near to reflective surfaces — and it makes it a poor choice if you need to achieve separation between different sound sources.



Published August 2011