Originally Posted by Jim1290
How about use Audyssey from the AVR to do equalizing, filtering, level adjustment?
Is MiniDSP does a better job other than Audyssey?
I am not properly educated with these HT stuff, so please keep teach me.
Audyssey generally does an awesome job of equalizing to a flat response and adjusting the levels. The MiniDSP doesn't take measurement so it cannot do Audyssey's job. To do that you have to get a calibrated mic and recording software. Once you have measurements, you can use the MiniDSP to dial in an EQ curve. So it's a lot more job, but once it's done, you can let the MiniDSP EQ your sub response. This is especially useful for receivers that do not EQ the sub channel (or doesn't EQ it proplerly). As I alluded to before, you can also use the MiniDSP after EQing using Audyssey for reaching a non-flat response of your liking.
Originally Posted by gogothedodo
I am using a PA-amp for my DIY subwoofers. Should I not apply a high pass filter in the Crossover block to protect my drivers..?
If your sub amp doesn't have any low-end protection built-in (limiter or high-pass filter) already, then I guess it should be a very good idea to use a high-pass filter. However, I'm not sure from memory what is the lowest frequency possible for the cut-off. The MiniDSP filter response may eat into your low-end if the cut-off is not low enough and/or the roll-off too shallow.
Originally Posted by Lesmor
My solution was to buy 2 x -10db attenuators fitted into the sub inputs but this resulted in levels too low for Audyssey, even -6 db caused problems.
Your application of the miniDSP looks like the ideal solution to my gain problem with the added benefit of perhaps using EQ
The MiniDSP sure is more expensive than a couple attenuators, but yes it can cut -10 dB off your signal and add EQ capabilities.
Originally Posted by Alan P
Why not just turn down the gain on the subs?
It's just that SVS (and Ken Kreisel apparently) said that the peak performances for the sub can be reached with the amp set to the max setting (no attenuation), which is the default setting now also. Note that it's not the amp gain per se -- the amp is digital, and the setting controls input attenuation as far as I can tell. Well, I have no idea if attenuating the signal prior to the sub ruins the peak performance thing, but in a small room with plenty of subwoofage, the problem is that you can't keep the sub amp set to max, then attenuate the sub signal and reach the levels Audyssey want using only the AVR. The MiniDSP then constitute a handy variable attenuator in this case.
Two schools of thought on this;
- EQ pre-Audyssey to present Audyssey with the flattest response possible requiring Audyssey to do less work - this usually is the best method if you are aiming for a flat bass response and you have very large peaks that Audyssey is having trouble dealing with.
- EQ post-Audyssey is usually the best method if Audyssey is giving you a fairly flat response on it's own and you would like to "un-flatten" the response to your preference (i.e. adding a house curve, mid-bass bump, increase in ULF, etc.).