Originally Posted by RobZL1
I am just confused. Per the REW graphs below, my PC-2000 seemed to run as good or better than I can initially run PC-4000. My ears agree.
I'm attaching the REW graphs of:
Green - PC-2000 @ SW Gain = 55%, Aud DyEQ=on, Aud SW Boost = ?
Blue - PC-2000 @ SW Gain = 75%, Aud DyEQ=on, Aud SW Boost = ?
Red - PC-4000 @ SW Gain = -7db [-60 to -0 range], Aud DyEQ = on, Aud SW Boost = off
The PC-2000 is equal or better.
I did a SVS 45-day return on my PC-2000 and also received a PC-4000 on the same day. I installed the 4000 in same exact spot, and I ran Audessey calibration (PC-4000 in Extended Mode (1 port closed)). I ran a demo movie clip and subjectively thought its performance was similar - equal or less - to the PC-2000. I then ran a REW measurement on the PC-4000 and found was nearly identical to the PC-2000. Is there a hypothetical where that should be the case?
PC-2000: Subwoofer gain at 50%; run Audessey; it puts SW1 trim at -4db; I then turn SW1 gain to 55% on the knob. I generally kept Aud SW Boost = On, but the adjustment = 0 db unless on a few occasions i increased it to +5 db for movies/demos.
PC-4000: Using SVS App, put Subwoofer gain at -10 db per SVS instructions (there is no physical knob; the app has a scale of -60 db to -0 db). Isn't -10 db almost maxed out? I wonder to myself; I select Port Mode = Extended Mode, and I plug 1 port. I run Audessey; during calibration Audessey makes me adjust SW gain to -17 db to get its measurement close to 75 db; after calibration it puts SW1 trim at -5 db. I then adjust PC4000 gain via app to -7 db because general advice here is to turn up physical gain after Audessey, and I want more "oomph".
REW data PC2000 vs PC4000
I am new to REW, just got the UMIK this week.
The other day I ran REW on the PC-2000. AVR MV = -20db, Aud Dynamic EQ = On. The only variable is I did not note if Aud SW Boost = on/off/+whatever db (?)
The PC-4000 today, AVR MV = -20 db, gain at -7 db, with Aud SW Trim = -5db, Aud DyEQ = On and Aud SW Boost = Off is the most REW will allow. If I try to increase SW gain, or turn on Aud SW Boost, I get a REW error saying it detected clipping and/or it ran out of headroom (a red 0db or -3 db message).
Let's start over a little bit. You are new to REW and Denon has got some wonky settings. First, it is important to make sure that your subwoofer is in a good location in the room. Doing a sub crawl, while measuring the results, is a helpful way to go about that. Don't worry right now about whether the PC4000 is in exactly the same spot as the PC2000 was in. Just make sure that the location for the PC4000 is where it sounds and/or measures the strongest.
Then, for whatever spot you pick, including the current one, do a new Audyssey calibration. But, let's do it a little differently this time. Try to get a trim level of about -11, but not -12. That means that you will probably need to be closer to the gain setting you originally started with. Ignore Audyssey telling you to reduce your SPL to 75db. It's okay to be higher than that in order to get a strongly negative trim level. On your Denon, you should be able to tell Audyssey to calculate after three mic positions. That will let you see what your trim level is before doing the full 8-point calibration. (All of this is covered in Section II-C of the Guide, linked below.)
Once you have finished calibrating, you can turn your AVR trim up to about -5 or -6 with the test tone adjustment. Don't
use the Denon feature called "Subwoofer Level Adjust". That actually resets your trim level to 0.0, and any trim you add puts you in positive numbers. That can result in clipping at any significant master volume. You can also turn-up the volume from the sub gain itself. Go as high as you like with that. If you want to be at -5 on the PC4000's digital reading, that is okay.
Now, listen to a movie with good low-bass content, and measure the results if you like. There won't be a lot of difference between the PC2000 and the PC4000 (in Extended one-port mode) above about 60Hz. So, for mid-bass they should sound pretty similar. The PC4000 in 16Hz mode, though, will have more SPL below that 60Hz frequency than the PC2000. There is a pretty good difference (~7db) at 50Hz and at 40Hz. Then, the difference levels-out more as you approach the port tune of the PC2000, and the difference is only about 3db or so. But, the difference is back up to almost 6db at 20Hz, and below 20Hz is where the real difference lies. With the right movie content, the PC4000 will produce much
more <25Hz SPL and TR. And, it will keep producing SPL below 20Hz, long after the PC2000 has run completely out of gas. But, the content has to be there. Otherwise, you will just hear a little more bass weight.
Here are measurements for the two subwoofers from different testing sources. You want to compare the 2m measurements for the PC2000 to the Audioholics measurements for the PC4000. You should beat those numbers in your room, since you will get some room gain. But, you will also get some room modes at random frequencies, which is why it is helpful to use REW to pick your best subwoofer location.
Sometimes, we are the victims of our own lofty expectations. The PC4000 is a better subwoofer than the PC2000. It is stronger below 60Hz, even in the Extended mode, and stronger down to 20Hz, at every frequency in the Standard mode. (The Extended mode, with its lower port tune, is specifically designed to give you more SPL <20Hz.) The sound quality should be subjectively better, and it has more versatility. But, you may not find an in-your-face, night-and-day difference when you move-up to a more powerful subwoofer, within the same family of subs, the way you would if you went from a sealed subwoofer to a ported one. Just give yourself a little time with this. The PC4000 is a very good subwoofer.