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stanza
09-23-2011, 12:14 AM
ok so on my HU Graphic EQ i can pick 100hz, 315hz, 1.25hz ect.. I know what picking these does but what does it do when it lets you adjust that from -6 to +6.. example if i tune my subwoofers to 80hz i know that is letting no frequency above 80hz play on my subs but what is it doing when i adjust it to say -5? or +3?

Another quick question.. Whats the difference between a voltage meter and a DDM?

(im in the process of tuning my system)

vaiboy
09-23-2011, 01:37 AM
You are mixing up the functions of an equalizer and a crossover. A crossover is what will filter frequencies above 80hz from being played by the subwoofer. An equalizer is a volume/level control that is applied to a specific range of frequencies. In the case of your graphic EQ, the frequencies you select would be the center frequency of the band that is boosted or attenuated. Graphic equalizers have a fixed bandwidth, so for example, if you select 100hz and +6, 100hz frequencies will be boosted 6dB, a range of frequencies above and below 100hz will also be boosted but the peak will be at 100hz. It is best to use the EQ to lower peaks, over boosting can lead to clipping which can damage your gear.

Moble Enclosurs
09-23-2011, 01:42 AM
ok so on my HU Graphic EQ i can pick 100hz, 315hz, 1.25hz ect.. I know what picking these does but what does it do when it lets you adjust that from -6 to +6.. example if i tune my subwoofers to 80hz i know that is letting no frequency above 80hz play on my subs but what is it doing when i adjust it to say -5? or +3?

Another quick question.. Whats the difference between a voltage meter and a DDM?

(im in the process of tuning my system)

Well, your not actually "tuning" your sub to 80*z, your applying a filter. The filter allows for the capacitor to roll off the unwanted frequencies at a steeper slope per octave than normal rolloff of the mechanics of the driver. Now, regarding the -5,+3,etc, this is a sensitivity control. It does not necessarily change volume, but is related to output sensitivity, where the negative values lower sensitivity, and the higher values "boost" sensitivity. It is considered an active part of the component where it applies the desired boost of the signal where the level is at, such as +5. +5 would say that it increases the sensitivity to 5 more decibels from the original sources output intensity. Anything above 3 is normally a major change and anything below 3 is a minor change. So, when tuning, if you measure the actual response and plot its curve, which I would recommend if you have an EQ to play with, then you must notes the differences in output in decibels on the graph related to the EQ frequencies of interest. You can then reverse the input from the peak or null in the desired range of that frequency, and it will smooth the tonality of the response for a "flatter" output. So, if the response curve shows that at 315Hz or in that octave range it is -6dB from the nominal dB level of the response, then you can set the EQ to +6dB to offset I and "equalizing" the band of frequencies in that 315Hz octave. Does that help?

Moble Enclosurs
09-23-2011, 01:53 AM
And the difference between a voltage meter and a DMM, is that the DMM does more than just the voltage related input output. It can do DC and AC current, resistance, and some of them can also do frequency dictation. A DMM can allow you to do much more in terms of audio.

stanza
09-23-2011, 06:32 PM
guys thanks alot for the information it did help.. ok so on my graphic equalizer i have the 8khz set at +6 and the 100hz set at +4 and everything else is either -1, 0, or +1. Is this ok? vaiboy mentioned that having these set to high can damage speakers? the reason i have the 8Khz and 100hz set so high is becuase it sounds great on those settings.. i am planning on setting my gain (as soon as the weather clears up) and my plan is as follows.. I am going to leave the 8khz at +6 and the 100hz at either +2 or +3 and i am going to leave the others at 0.. i am going to leave my HPF on 100Hz and my subwoofer setting on 63hz +2.. i am going to use a -3dB 50hz test tone to set my gains. Then i am going to set my amps filter freq. to around 60hz. is this a good plan? or is there something you guys would set differently. i only listen to rap music so i am aiming for my bass to be crisp and hit hard. i prefer a crisp hard hit over SPL.

Also i picked up a DMM at a local hardware store for $15.. i know how to use the AC volt meter but how to i use the Ohm meter and wat can that do for me?

Thanks for the great info guys.

stanza
09-23-2011, 06:37 PM
another thing about my EQ on my HU.. as i mentioned, i have my 8Khz set at +6.. when i put the 8Khz band to 0 it sounds really muffled and not good.. does that sound normal? it sounds fine at +4 but it sounds even better maxed at +6. This is why i said i am going to leave it at +6 when i set my gains.. or do you guys think i should just set all my EQs to 0?

Moble Enclosurs
09-23-2011, 06:45 PM
another thing about my EQ on my HU.. as i mentioned, i have my 8Khz set at +6.. when i put the 8Khz band to 0 it sounds really muffled and not good.. does that sound normal? it sounds fine at +4 but it sounds even better maxed at +6. This is why i said i am going to leave it at +6 when i set my gains.. or do you guys think i should just set all my EQs to 0?

When tuning originally, yes everything should be at zero. You first want to find the maximum volume level with minimal distortion first. Then use that volume to set tuning the rest of the system with the EQ. This is why he said setting them at a positive can cause damage.......due to distortion. And some inaudible that will damage over time. But generally, a well build system should need minimal EQ if any as long as you get the right drivers with the right sensitivity and frequency responses to cover the spectrum and of course enclosure area makes a big difference on those responses. But if you have to tune, figuring for max volume, then using that and the tuning frequency (60, 50, 40) to set the gains, then do fine tuning after that likely to lower peaks rather than increase dips will be the best bet.

stanza
09-23-2011, 07:16 PM
ok i guess ill just set everything to 0, use a 50hz test tune and see how it sounds. Now if i do that and it doesnt sound good to me, is it "dangerous" to mess with my EQs? (like putting my 8khz to +6) Should i turn back my gain a bit more then a hair after distortion level to leave room to mess with my EQ?

Another thing, if i use a 50Hz test tone and set my amps filter freq. at 60-63hz and my HU subwoofer setting at 80Hz, is that defeating the pourpose of using a 50Hz test tone?

Also do you know how to use the Ohm setting on DMMs? what can the Ohm setting do for me?

Thanks Moble Enclosurs, really helping me out here.

Moble Enclosurs
09-23-2011, 08:28 PM
ok i guess ill just set everything to 0, use a 50hz test tune and see how it sounds. Now if i do that and it doesnt sound good to me, is it "dangerous" to mess with my EQs? (like putting my 8khz to +6) Should i turn back my gain a bit more then a hair after distortion level to leave room to mess with my EQ?

Another thing, if i use a 50Hz test tone and set my amps filter freq. at 60-63hz and my HU subwoofer setting at 80Hz, is that defeating the pourpose of using a 50Hz test tone?

Also do you know how to use the Ohm setting on DMMs? what can the Ohm setting do for me?

Thanks Moble Enclosurs, really helping me out here.

That is a good idea. It can be dangerous, yes. The best bet is to get drivers that have good sensitivity for the frequency range. For instance, if your mids do not hold up with the tweeters, then instead of boosting the mid frequencies, either lower the gains on the tweeters or get higher sensitive mids.
Now regarding the gain, yea, setting it back a bit can help. A lot of people will recommend this, and is a great idea.

Ok. the filters from both the HU and the EQ are going to help each other. The best best is to set the HU at the highest filter cutoff that it can use for the sub, or not even use it if that is an option so the HU gives the amp and EQ the full band to play with, then use the amp filter to set it. But what will happen if you set the HU at 80 and then the amp at a lower filter, then the 80Hz filter will have a much higher rolloff than needed to blend in with the mids correctly. So, if you cannot get rid of the HU filter, then the best best is to let it control the filter, and set the amp filter higher than 80hz so it does not interfere with the slope drop off AT 80hz as much. But no, that does not defeat the tone, just will increase the cutoff more rapidly, and when that is adjusted further, it may be very very sensitive to any minor changes after it is tuned.

Now, with the DMM, the ohms settings is based on resistance. This is helpful in figuring for an unknown resistance of the overall circuit. You can verify the resistance of the drivers when loaded, and figure or find for other factors such as current, power, and voltage, which can then in turn be used to find other factors of a circuit, such as impedance matching, current load, voltage drop, and other things to make sure your system is running properly and connected properly. Most if the time I use resistance is for verifying and fixing problems with a loss on the load or verifying load resistance to figure for output and impedance curves for tuning factors and such. But really because it is a DMM, the posibilities are virtually endless in audio.

stanza
09-23-2011, 09:12 PM
great information man.. thanks a lot.

But about ur idea of putting my HU's subwoofer setting to max (which is 125hz, i do NOT have the option to turn it off).. If i did this, then wouldnt my HU send every frequency below 125hz to my subwoofer? which would defeat the pourpose of having my amps freq filter set to say 50hz?
or..
Are you saying by setting my HU's subwoofer setting to max (125hz) and my amps freq filter at say 50hz, i will have a nicer blend and a cleaner sound coming from my subs?

sorry lol, im a little confused.

stanza
09-23-2011, 09:26 PM
nvm i now see where u said set the amps filter freq to 80 or higher.. wouldnt it be best to set my amplifiers filter frequency to whatever my HUs subwoofer setting is at? For example, if i had my HU sub setting to 125hz and my amp set to 80hz, would that make it so im not hearing anything in the 80 to 125hz range? if im just asking pointless questions let me know lol

Moble Enclosurs
09-23-2011, 09:26 PM
great information man.. thanks a lot.

But about ur idea of putting my HU's subwoofer setting to max (which is 125hz, i do NOT have the option to turn it off).. If i did this, then wouldnt my HU send every frequency below 125hz to my subwoofer? which would defeat the pourpose of having my amps freq filter set to say 50hz?
or..
Are you saying by setting my HU's subwoofer setting to max (125hz) and my amps freq filter at say 50hz, i will have a nicer blend and a cleaner sound coming from my subs?

sorry lol, im a little confused.


Oh, that's ok. Ummm...no what I mean is set the HU as high as possible and set the amp filter to the 80Hz if possible. And yes, that means the HU will send all frequencies below 125Hz to the sub. You have to realize, that normal subwoofer range can go into the mid 100s due to the tonality of bass guitars and such that do not go below 50Hz normally, so having it set high is not such a bad idea in some cases where distortion is minimal and the driver is great for sq and the enclosure controls the effects of higher frequencies by utilizing a physical cutoff filter in a sense anyhow. It can actually get pretty complicated. But simply put, just mess with it until it sounds good for YOUR ears and no one elses. But yea, doing the HU to full subwoofer range and let the amp control the HF cutoff at around your desired 80Hz or so, and then it will blend pretty well with the mids if the mids are capable of producing accurate tones around 60Hz and above, which most are if they are good SQ drivers. There will always exists a dip in the response from each range of frequencies, but the point is to make it inaudible as possible (below 3dB dips are great).
But setting the amp at 50 will limit the 50-125hz range to blend better with the mids. A lot of people confuse output with clarity and pressure with intensity. You may find that doing it properly may not be what you like to hear.....and a lot of people are that way....that a flat response is just not what they like.
The best bet is to play with it until you get the sound you want.

Moble Enclosurs
09-23-2011, 09:27 PM
nvm i now see where u said set the amps filter freq to 80 or higher.. wouldnt it be best to set my amplifiers filter frequency to whatever my HUs subwoofer setting is at? For example, if i had my HU sub setting to 125hz and my amp set to 80hz, would that make it so im not hearing anything in the 80 to 125hz range? if im just asking pointless questions let me know lol

Close! not that you wont hear anything, but the rolloff will be in that range for the mids to kick in, yes. You got the idea. :)

stanza
09-23-2011, 09:34 PM
awsome.. thanks for ur help man. can i pm you with another question i have?

Moble Enclosurs
09-23-2011, 09:54 PM
Sure, but I am gonna get off of the forum for a bit....the wife wants to watch a movie with me since I can't really do much else right now, lol. Ill get back to you soon. PM me anytime!