Monoblock Settings

[Ace]

:sad_smile: any sifu here knows care to explain and how to adjust to match a person listening pleasure?

how to get the most out of it on a monoblock amplifier?

Variable Subsonic filter : 15~30Hz, 18dB /oct
Variable low pass filter : 30~240Hz, 24dB/oct

Thanks a lot....:emoticon_U:

 

[appleyard]

i dont know what is your question was but if its about subsinoc filter and LP crossover .... well set your subsoninc filter to 20hz range and LP to 100hz.

It wont increse your listening pleasure but it wont damage your sub either.

And i dont understand by "get most of the mono amp" thing?

 

[Ace]

well, frankly I'm using a monoblock firing a 12DVC sub on my car. Usually I played with the gain settings. Wheres the other settings was set by my installer which is below

Variable Subsonic filter : 15~30Hz, 18dB /oct
Variable low pass filter : 30~240Hz, 24dB/oct

When I say that to "get the most out" means that can we play around these available settings and in a way where we can actually comes out with a recomended settings that can be set full for SPL and when it is not needed we can actually set it for SQ. I tried experiment with it and found that it can turn my bass into soft/deep and in another way into hard pounding maniac.

appleyard, you were suggesting that subsonic filter to 20hz and lp to 100hz. Is this a common settings to play safe?

 

[appleyard]

for subsonic filter - read my previous post
for LP filter - read my previous post

Subsonic filter is where it prevent your sub to play freq. that may damage your ears. Freq. below 20 hz are considered damaging if exposed to a period of time thats why its important to set it correctly.

LP filter is to prevent your sub to play freq. that is out of its range. You would want your sub to play high freq as it may damage the sub. Its the same with components xover.

Rule of the thumb is Subsonic is set around 20Hz range and LP around 100hz range. You can set LP to 70hz or 80hz or 90hz depends on your preference and what range do you want your sub to play.

Both setting will not increase your SPL as i said will prevent your sub to be damage.

Soft bass and hard bass or low freq bass and high freq. bass..... is about your sub capabilities and the enclosure not the gain settings. Dont be confuse that if your turn up your gain means your will get hard bass. Gain is where you match your amp input with HU output. Normaly you turn up gain until your sub reach xmax.

 

[Ace]

Thanks for the tip. Will try to do that. I understand that these settings doesn't give me any spl. But the thing is when I played around these settings my bass does sounded differently. It can become hard pounding or deep/soft bass for audiophile songs. When the bass play hard (but not as tight as seal encloser), you can actually put more gain to it which sounded louder (probably because of the higher frq). But when it is soft and deep, increasing the gain doesn't do any help but worsen it. I'm just curious as in teory and practical doesn't seems to be as expected.

 

[Kippo]

appleyard,
please read more on filters, freqs. as u got ur facts wrong.
freq. does not damage ears, it is the Sound Pressure Level i.e. decibels (dB) i.e. the loudness. Any frequencies that are loud will damage your ears whether it is 20hz or 20khz.


Ace,
subsonic filter is actually a high-pass filter. It filters freq. below its setting.
What is subsonic? it is freq. that is below human hearing which falls in the range of 20hz - 20khz.
But what is its main purpose in sub-woofer amp? it is to prevent your sub to over-excurt at the amount of power given to the sub.
for example, if ur sub max. excursion is 20mm and at 25hz & 1000W RMS, your sub excursion will be 22mm.
If you let this happen, ur sub may get damaged. So you have to set subsonic filter to filter out freq. lower than 25hz i.e. u have to set it to eg. 27hz.

Application which needs subsonic filter to be set properly is mainly on ported box where u need to filter the freq. at which ur sub will 'unload'.
Also in high power sealed box (in slightly larger box) application because generally sub + sealed box will have two high excursion peaks i.e. in the middle freq. and at the lower end freq.
So for those who believe sealed box is safe, think again.

Low pass filter is used to set which freq. u want your sub to play.
sub-Bass freq. ranges around 150hz ~ 20hz (in fact even lower but that is not in music audio scope).
So on the upper range bass freq., you will feel the bass is pouding or hard as what u call it.
On the lower range bass freq., you will feel the bass as rumbling or softer as u call it.

So where to set Low pass filter?
It depends on the bass music u like. If u like hard pounding bass then set your low pass filter higher. If you do not like hard pounding then set it lower.
It is all about ur music taste. Dont bother with the numbers. Set it according to what is pleasing to your ears.


once you done all the settings, do google and read about 'bass upfront illusion'.

 

[Ace]

kippo, thats some great info and tips. At least I have some understanding on what those settings are. I think i will be having hard time to adjust my sub. I'm using Prokick DG-1200 mono on 2ohm at 700wRMS to supply juice to my Boss Audio IQC-DVC12 (freq, if I'm not wrong is 25 Hz – 2.2 Hz) mouted band pass. The above is the settings that i found on the amp. Any suggestion from your expertise before I try with my own ears? Thanks man.

Oh..I got some tech info on 'bass upfront illusion'. I don't have any problem with that as I got car put up with dynamatt almost all round. I put it down below so some other forum members can read about it.



_____________________________________________________

Achieving Up Front Bass in Car Audio
What is "Up Front" Bass?
Up front bass is the psycoacoustic (that's a big word, huh) phenomenon (another big one) that makes us think that our rear mounted subwoofers are actually in front of us. Hence the term "up front" bass. Basically it's a way to trick your brain into thinking your subs are in the front of your car audio system. This is very desirable for sound quality listening so that all your music appears to come from the same place (in front of you). You don't want the high hat to come from the dash and your kick drum to come from the rear.
How to Achieve Up Front Bass
There are several factors that need to be achieved in order for this trick to work. First, we need a car audio subwoofer system that is capable of producing low frequency bass. This is not a problem for most systems due to cabin gain. Second, we need to control the frequencies that this subwoofer system produces. Specifically we need to cut off the high frequencies from the subwoofer system. The human ear isn't able to detect the location of low frequencies nearly as well as it can high frequencies. By limiting the subwoofer system to play only the lowest frequencies (those we cannot locate by ear) we have the first part of the equation, low bass only. This is achieved by using a subwoofer crossover frequency in the 40-60Hz range combined with a very steep slope of 18-24dB per octave.
Now that we have our subwoofer system producing only the lowest frequencies we need something to fill in from the those frequencies on up. This can be in the form of a door mounted midbass speakers or smaller subwoofers mounted up front (usually in a small enclosure located in front of the front seats). If your front speakers are capable of reproducing frequencies down to 50Hz with authority (and really very few do) then you won't need separate midbass speakers in the door or custom enclosures.
You can also achieve bass up front by having your subwoofer system up front. If you have a vehicle with a rear/mid mounted engine with the trunk in the front then that's where you can place your subwoofers. Clearly this is the easiest way to go but very few vehicles have this option. The other option for front mounted subwoofers is to place woofers with small enclosure requirements (usually an 8" pair) in custom enclosures mounted just ahead of the front seats (in the area between the seat front and the back of your legs). If you go this route be sure to secure the subwoofers so they don't want to slide forward.
How to NOT Achieve Up Front Bass
One of the quickest way to ruin the illusion of up front bass is to have the rear of your vehicle rattling. It doesn't take your brain long to figure out that the subwoofer is in the same place as the rattling body panels. Take care of these noisy panels by using a combination of sound deadening sheets (Dynamat or similar), expanding foams and other sound deadening materials. Then using a test tone CD sweep through the bass range and see if certain frequencies cause other panels to vibrate. Sound deaden these areas and repeat until your rattles are taken care of. Then sit back and enjoy your new car audio system. Just make sure you leave enough juice to start the car.


:)

 

[Tohsan]

Final conclusion about the monoblock setting, its all up to your personal preference to which you are comfort with,then thats the best setting for you.:regular_smile:nothing is fixed n definite!

 

[hi1983]

one more, if say monoblock setting maximize, don use class D monoblock to push speaker, only for Subwoofer, Class D will make sound above 100Hz very very teruk, so sometimes hear people say its Class D is suck but acually he don understand. so if you want your sub to play higher hertz maybe say above 100 more, than maybe class D may not suit you.

for me, although say the none directional hertz is about 80hz, but it is also effect by the crossover slop ( low pass) for mine, i set at 65hz 48db slop so will not make the vocal suck up. how ever i have 2pair 6.5" mid bass at front door for produce better mid low frequency to balance, becos of very slop subwoofer will not enchance the mid bass anymore. ( 2 6" close together for hertz below 65- 150, also 24db slop)

this setting same as very good english ACE says Upfront bass, but for linear i need two mid bass,

than will became clean, for subsonic filter, acually if say normall recording cd will not go as low as that,, but if say the woofer only can handle probely upper 40hz, than it needs, but say if the subwoofer can handle easy at 20hz or 25hz (normally very few) than no need subsonic filter aready,, most Hu also can not produce below 20hz sound scorce.

 

[hi1983]

yes tohsan,, while beside that we still need to understant the theory to maximize 1 thing.

 

[Kippo]

hi983,
where u have the information that above 100hz, class D amp is not good?
usually low pass filter in class D amp is up to 200~250hz.

do you think crossover slop of 48db/octave is overkill? especially for subs?

have u tried using different crossover slop & notice any difference?
Do you think that the difference that you have heard is due to phase difference rather than how steep is the crossover slop?
phase difference is best rectified by speaker placement.

and ur remark of sub-sonic filter on subs are out of place.

and ur remark on non-directional frequency affected by crossover slope is wrong.

and your explaination is very confusing.

please read more.

 

[hi1983]

hi, i just share, however i din say crossover slope are related with non-directional frequency,?? what you mean, directional frequency is 60-80 hz base on diffrence people feel, however why put very step slope is to eliminate the higher frequency to produce behind at the car boot from subwoofer.. i mean this, for up front bass. since on only with 12db slop @ 80hz at subwoofer, there are still about 1/2 level of sound produce at 120hz from subwoofer, and 1/4 @ 160hz.

becos altough put at crossover point of 80 or 60hz, they still have level of higher frequency produce by subwoofer.

and ur remark of sub-sonic filter on subs are out of place, sorry don understand what you mean.

for class D amplifier question, what i say is the class D for speaker is not as good as normal AB on soundquality, this most ppl knows. i say for higher hertz produce , but class D is best on power. if you think is wrong pls share some idea.

hi, we are sharing knowledge, although some may wrong,

 

[Kippo]

hi193,
u said that above 100hz, class D amp is teruk.
but class D amp has low pass filter up to 250hz.
but why u said above 100hz? there must be a reason for it.

on subsonic filter, u said only a few sub can handle 20hz~25hz. Is it due to sub design?
and u said that the sub-woofer can only handle eg. above 40hz and this is where sub-sonic is required. But why that sub can handle only above 40hz?
what is the factor?

 

[Kippo]

hi, i just share, however i din say crossover slope are related with non-directional frequency,?? what you mean, directional frequency is 60-80 hz base on diffrence people feel, however why put very step slope is to eliminate the higher frequency to produce behind at the car boot from subwoofer.. i mean this, for up front bass. since on only with 12db slop @ 80hz at subwoofer, there are still about 1/2 level of sound produce at 120hz from subwoofer, and 1/4 @ 160hz.

becos altough put at crossover point of 80 or 60hz, they still have level of higher frequency produce by subwoofer.

yep but why use steeper xover slope (and spend more unecessary money) if it is no longer audible?
even top brand sub amp does not have 48dB/octave xover slope on its low pass filter.