I am a recent convert to the new high resolution formats. There is just no doubting the superior sound from dvd-a and sacd discs. For me, there was no turning back. Heard it once and that was enough. As has been mentioned by several others, it can revitalise your listening pleasure.
I am still attempting to extract the best sound out of my system, and I am having a great deal of fun trying.
One aspect of dvd-a and sacd that is often referred to, but which I have no understanding is "bass management". I often read that the new formats limit ones ability with respect to this. Could one of you please explain to me exactly what bass management is?
J. Vigne
Unregistered guest
Posted on
It is the ability to control the hinge point of the x-over to the subwoofer and the front main speakers. It is similar to the bass management that is available on Dolby Digital processors. It will also give the ability to adjust the relative levels of the main speakers to the subwoofer. Most of the more recent players have this ability when used in the hi-res stereo or multi channel set up.
and that is how the bass is distributed in your system.
through the bass management you can tell the system to send bass frequencies from a certain level say 80hz on down "adjustable" to your subwoofer and by choosing large or small speakers you can tell the system weather or not to send those frequencies to your regular speakers as well or not to send the bass from a certain hz on to your speakers "adjustable" if they are of a smaller size and can't handle the bass frequencies that low.
or if you have no sub at all and want to send all the bass to your speakers you can do that as well.
Unless you have excellent full range tower speakers all the way around your surround system you will need bass management.
It becomes even more important on DVD-A and SACD surround. Due to studio copyright laws, currently most outputs on dvd-a and sacd need to be in analog due to the fear of the studio's that you will make exact copies.
Your universal dvd player uses a DAC to first convert the digital signal from the disc to analog and then goes to the receiver or pre-amp where it has to go through another DAC to go back to digital in order to be processed for bass management--and any other effects you may desire.All processing takes place in digital mode.
A few companies, Pioneer Elite, Meridian, new top of the line Onkyo/Integra, and Denon (a couple of others too) use either proprietary firewire (that often isn't compatible with other brands) or even better, universal 2-way firewire (such as on the Pioneer Elite 2 receivers and 2 dvd players.
This allows the digital signal to be sent without going through a DAC through the firewire cable (i-link) to the firewire (i-link) equipped receiver, where it is digitally processed for bass management. Only after that does it go through one DAC to become an analog signal for the amp. Obviously, these firewire transfers have to be encrypted to allow for no digital copying.
Some dvd players have no or poor bass management. Same is true on receivers (usually the lower end), but you can find receivers with fairly sophisticated bass management, or one can buy separate bass management components from companies such as Outlaw Audio.
If you use different model speakers for your fronts and surrounds, Harman Kardon now makes bass management individually tailored for at least 4 speakers.
In my preferred system (I have one upstairs and one downstairs) I have the same speakers in the front and the rear. Besides an advantage in bass management I find it is even a bigger advantage in having identical timbre and frequency response. While most receivers only specify "large" or "small", rather than a more sophisticated exact Hz number for crossovers, most quality subwoofers have exact crossover designations--usually in 20 Hz steps from 60HZ to 120HZ. This covers most bookshelf speakers.
Any good bass management system allows your bookshelf speakers to play without strain, as all the low frequencies (which require the most power) go to the subwoofer. Investing in a very good self-powered subwoofer is always a wise move for optimal surround enjoyment.
Really, really good DVD-A recordings are often in 4.0 or 5.0, therefore this whole "bass management" issue goes away. It is a very misleading term. If you still wish to use your active sub to cover frequencies your main speakers can't handle comfortably, then you just set the crossover, the frequency below which the sound will be reproduced by the sub, and above which the sound will be reproduced by the main speakers. Then you should get their relative levels about right (units of dB). It is just "suck it and see", really, but some people advocate use of a sound pressure level meter. The best SPL meter is your own ears.
If there is a true ".1" track on the disc, then "bass management" was in the hands of the recording engineers, and they either got it right, or they didn't. There again, if you have small main speakers, you can add low frequencies intended for them to the ".1" channel, using the variable crossover.
More important, for good, accurate, positioning, is getting the speaker delays (aka "channel delays") right.
I have main speakers that roll off -3 dB at 40 Hz. I have just played a 4.0 DVD-A disc, including some of the most most wonderful and thuderous organ I have ever heard. I had to go and check the sub was not on. It wasn't. I personally wish the active sub had not been invented. It was a low-cost solution to getting deep bass. When you move to real listening, it is mostly a nuisance, and the aim, as with all speakers, is to make it invisible - meaning you cannot hear when it kicks in, nor where its sound is coming from.