Hello guys, i am starting this thread as a personal "Ask and learn" topic, but i hope it would help a lot of people in the future.
I am in the search of buying a sub woofer, and i have been searching the internet for the best candidate in my budget (500€ top).
As i was searching for it, i learned and discovered a lot of things that opened my eyes, and let me tell you this.... i didn't like what i saw.
Buying a sub is a nightmare as you keep learning and learning. But in the end that seemed to be the easiest thing in the sub matter.
I found out that when you buy a speaker, and especially a sub, you will likely not get 100% the best performance that you could get in your room. This is because of the room size, room decoration, room shape, room bass management. You will have things like Nulls and Peeks. You will have floors moving and trembling. You will not be able to 'hear' your sub, because it will be in the wrong place in your room, or you will be unsatisfied because the speaker is too small to cover your open space.
When i was asking people how should i calibrate my sub, what is the best way to configure a sub, i was getting the same stupid answer over and over again. "Each sub behaves differently in every room, so we can't tell you how to configure your sub". Well my answer to them is 'bulls**t'!. Yes i accept the fact that the VALUES that each configuration need are not the same, but the way and the process is the same! You just have to find what are the best values - configs for your place. In order to do that, you need someone to tell you, that you have to do this and that.
Since i am still learning and have a lot of questions, i have been asked to open a new thread, so that we can keep it together.
The following questions have been asked in the SVS PB-1000 topic, so i am just copy-pasting them here.
As i said, i am not an expert or anything. I am a noobie who wants to stop being a noobie on this subject. I will use the second post, so that i can concentrate all the info i am finding over the internet about subs, and people with real life experience can comment on them. It will be a guide on how to configure your sub to reach the best values you can get. I am guessing some will be VERY easy to do, and some will be very hard to do. We will see
So here are the questions i have made so far and the answers i have got from some very friendly guys in here (Thank you all)..
PLEASE keep in mind that the following questions have already been asked and answered in another topic. I will continue asking questions, and of course everyone can ask, so that we can get answers...Q) Can i use two different subs in the same room?
A) You could, but don't try it. It will be a nightmare matching them both, and for that you need more than average knowledge. Suggested opinion is to not try it, as it will cancel each other out.Q) Ways of making my sub sound better? (This is just a simple question, with a fast and simple answer fom ElJay)
Q) what would someone gain from using a device such as MiniDSP for his sub.
Assuming the rest of your system is already in place:
Step 1: Connect the sub to your AVR.
Step 2: Do a sub crawl to determine which 1-3 locations provide the best output at the listening position. Place the sub in the location which offers the best compromise between output and real life (aesthetics, WAF, etc.)
Step 3: Run your AVR's auto-calibration program.
Step 4: Go into the AVR's speaker set-up menu and tweak channel levels by ear.
Step 5: Sit back and enjoy.
Beyond that, you can:
- Purchase an SPL meter to measure - and, optionally, to chart - the frequency response (FR) of your speakers and sub.
- Purchase a device such as a Dayton OmniMic - or purchase a microphone and use freeware like REW - to view various elements (levels, EQ, decay, etc.) of your system's response on a laptop in real-time. If you have additional equalization equipement - see next bullet - this real-time visualization is very helpful.
- Puchase an EQ device such as a miniDSP, and peform additional calibration tweaks.
- Et cetera.
A) "the ability to EQ the sub for a flatter in-room response."Q) so i suppose that our goal when we EQ a sub (or a speaker) is to have a flat response. got that. but how do we achieve this? what do we 'change - configure' in order to achieve that. i have read something about octave, but that made me even more confused.
A) A flat response (see a graph of any SVS sub on their website) means that between a range of frequencies - say, 20Hz to 150Hz - a sub plays a certain level of output with a variance of no more than 3dB above or 3dB below (+/-3dB) that level. IOW, output remains consistent across the frequency range. This is a good thing.
In-room response, because of interactions with boundaries and other objects, is unlikely to be flat: There will be peaks and nulls (the opposite of peaks) at one or more frequencies. Room EQ software - which you get with Audyssey or miniDSP - manipulates (to the extent that it can) the signal that is sent to the sub to compensate for those peaks and nulls. It tries to "flatten" the FR curve.Q) 1) a peak means that the sub sounds higher than it should and null means that you can't hear as much as you should?
2) what the dsp changes in order to achieve that result? (flat response) it lowers / higher the db when it detects sounds at specific frequencies? for example when it sees that is used to be peaks there, it lowers the db of the sound coming in, and when it detectes a sound at a null frequency, it adds more db?
A) Yes. A peak at a frequency means that that frequency will be played louder than the rest of the frequencies in the sub's "flat" (+/-3dB) frequency range. A null means the frequency will be played more quietly.
Very un-technically-speaking, the DSP would test the sub, measure the response and load into memory an EQ profile that would take all incoming signals and boost* or cut them as required to output to the sub a "flat" signal to play.Q) what is a stereo sub? 2 subs or connection related?
A) Stereo subs usually refers to two subwoofers. Stereo bass, as I (possibly inaccurately) understand it, requires two subs, each receiving the distinct low-frequency content of the channel with which it is associated. Example:
- run a connection from the left main speaker-level output on your AVR to the left speaker-level input on the subwoofer, and then from the left speaker-level output on the subwoofer to the left main speaker; and
- run a similar connection for the right main speaker.Q) ah.... ok i understand. well i suppose the AV receiver should do that on it's own. i don't think the subwoofer should give power to the mains, since it doesn't have enough power. isn't that right?
A) The sub never powers the mains. The AVR sends the powered signal "through" the sub to the mains, but the circuitry within the sub takes just the signal and uses the sub's amp to power the signal for the sub only. (And the crossover - or low-pass filter - determines the range of the lower frequencies that the sub will play.)