![]() So the SMBus itself provides the protocol to transfer information to and from a host device such as a laptop PC.Īt this point, most non-laptop users might be thinking about disabling the SMBus Controller by using the 'Disable in this hardware profile' option inside Device Manager to gain an IRQ. Originally conceived by Intel, the SMBus is intended for so-called 'Smart Batteries' that haveembedded electronics to hold data, measure the batteries' current state, and calculate and predict the batteries' future performance. The System Management Buss is a two-wire interface that enables system and power management related chips to communicate with the rest of the system. ![]() However, if you've ever investigated the IRQ list, you might have noticed a device in your IRQ listing containing the words 'SMBus Controller' and wondered what it does. In the past I've looked at disabling unused serial and parallel ports, along with USB Universal Host Controllers, to regain some interrupts so that soundcards have a better chance of getting a dedicated IRQ. ![]() The five-band controls are still all 'in circuit', but this time the default Flat preset is flat to within +0/-0.5dB over the entire audio range from 10Hz to 20kHz, emerging through 24-bit converters with noticeably less background noise. Just to prove that the tailoring is completely separate from the five-band EQ, the screenshot also shows the result when you replay SW1000XG sounds through Kenton's Plugstation. So in addition to flattening out the response, my settings raise the overall level by around 2dB, which improves this situation a little, and yes, I did try to find some EQ settings that raised overall level by around 6dB overall, but it proved impossible to simultaneously keep a flat response. ![]() This has annoyed quite a few musicians who find the final output level lower than expected, and therefore not making the best use of the available dynamic range. However, there's another advantage of using these settings as Yamaha reduce the internal digital level by 6dB before it reaches the output effects and EQ section to allow some headroom. To achieve this new response, you need the following settings: band one and five remain unaltered, while band two has 1dB of boost at its default 500Hz frequency band three has 1dB of boost at 1kHz and band 4 has 2dB of boost at its default 4.0kHz, with a lower Q setting of 0.4. As you can see from the screenshot in figure one, the new settings give a noticeable improvement in flatness to within +0.25/-0.35dB between 10Hz and 12kHz, although the audio improvements are admittedly subtle. Previously, I've managed to come up with some adjusted settings that provide a significantly flatter response by using a special set of test tones and a spectrum analyser plug-in, but I've managed to flatten this response further with the aid of Audio Analyser. Here are the frequency responses for the SW1000XG in its default state as reported by RightMark's Audio Analyser 4.0, with my previously published settings for a flatter response, the new tweaked Q setting and through the Kenton Plugstation.Sadly, you can't flatten this out by simply applying 2dB and 1dB of cut at 40Hz and 10kHz respectively since the five-band EQ curves are completely different. Its five bands have presets labelled Flat, Jazz, Pops, Rock, and Classic, but unfortunately the Flat preset doesn't live up to its name in the SW1000XG, giving a noticeably warm response due to almost 2dB of boost at 40Hz, and about 1dB of extra 'air' at 10kHz due to subsequent EQ tailoring. I provided modified values for the five-band EQ that forms part of Yamaha's custom SWP30 chip in SOS November 2000, and this sits near the end of the signal chain on not only the SW1000XG soundcard, but also the MU100, MU128, the A3000/4000/5000 samplers, and various other Yamaha synths. In last month's PC Musician I looked at using RightMark's Audio Analyser for basic soundcard testing, although I've also been finding it useful to help make the response of my Yamaha SW1000XG soundcard flatter. We take a look at the EQ response of the SW1000XG soundcard, the possibility of disabling the SMBus to gain an extra IRQ, and more advice on managing your updates.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |