Looking to run a true 5HZ signal to my Sub woofers but think my anthem receiver will Bottle neck this.

[Allen Vos]

So as many of you know from a previous thread I am builiding 4 Mach 5 auido ftw-21" sub woofers in 4 seperate sealed boxed. Using Winisd and the cone excursion function I am able to get these subs down to 5HZ with 1200 watts of imput in a 6.2 cubic foot sealed box, with only 23mm of cone excursion, which is well under the 29mm spec of the sub travel

So I will list my entire setup here with regards to imput source, reciever, mini dsp and amplifier.

Anthem MRX1140 Reciever, which outputs an unbalanced sub out signal to the Mini DSP
Zidoo Zx9 media player, is connected to the Anthem Via HDMI
Mini DSP Flex HTx hooked to the CVR amp via TRS to XLR cords for a true balanced signal
CVR D-1004 Amplifier powering all 4 sub woofers

The issue I am going to run into is that the Anthem reciever has a frequency cut off at 20HZ, so If I wanted a true 5HZ signal into the subs, I would have to have the mini DSP Flex HTx reproduce that signal. Since that signal does not come from the Anthem reciever, the mini DSP cannot restore or cleanly boost a signal that has already been filtered out by the AVR without introducing severe noise and clipping.

Another option would be to connect a USB cord from the Zidoo box direct to the mini DSP so it would get a true 5HZ signal to the CVR amp and avoid the 20HZ cut off in the anthem reciever.

I do understand a lot of this to a certain extent, however this is very much uncharted territory for me as I have really only played with store bought stuff most of my life and a small amount of car auidio.

I have not purchased the Mini DSP Flex HTx or the CVR D-1004 amplifier yet, so if there are better options for what I would like to do, I would appreciate some imput and Im more than willing to listen to advice.

 

[TLS Guy]

So as many of you know from a previous thread I am builiding 4 Mach 5 auido ftw-21" sub woofers in 4 seperate sealed boxed. Using Winisd and the cone excursion function I am able to get these subs down to 5HZ with 1200 watts of imput in a 6.2 cubic foot sealed box, with only 23mm of cone excursion, which is well under the 29mm spec of the sub travel

So I will list my entire setup here with regards to imput source, reciever, mini dsp and amplifier.

Anthem MRX1140 Reciever, which outputs an unbalanced sub out signal to the Mini DSP
Zidoo Zx9 media player, is connected to the Anthem Via HDMI
Mini DSP Flex HTx hooked to the CVR amp via TRS to XLR cords for a true balanced signal
CVR D-1004 Amplifier powering all 4 sub woofers

The issue I am going to run into is that the Anthem reciever has a frequency cut off at 20HZ, so If I wanted a true 5HZ signal into the subs, I would have to have the mini DSP Flex HTx reproduce that signal. Since that signal does not come from the Anthem reciever, the mini DSP cannot restore or cleanly boost a signal that has already been filtered out by the AVR without introducing severe noise and clipping.

Another option would be to connect a USB cord from the Zidoo box direct to the mini DSP so it would get a true 5HZ signal to the CVR amp and avoid the 20HZ cut off in the anthem reciever.

I do understand a lot of this to a certain extent, however this is very much uncharted territory for me as I have really only played with store bought stuff most of my life and a small amount of car auidio.

I have not purchased the Mini DSP Flex HTx or the CVR D-1004 amplifier yet, so if there are better options for what I would like to do, I would appreciate some imput and Im more than willing to listen to advice.

Why on earth would you want to do that? No cone speaker will ever reproduce that. The cone my vibrate, and you may destroy a perfectly good driver, but you will NOT generate a 5 Hz sound wave. For a start the cone will move but nothing will be generated. The Fs of a moving coil driver is essentially the lowest frequency it will generate, although it may make sound, but the cone will be breaking up and you will get frequency doubling. So if driver Fs is 23, and you feed it 15 Hz, you will likely hear 30 Hz, which is still very low and you may think you have generated 15 Hz, but you won't have.

 

[Allen Vos]

Why on earth would you want to do that? No cone speaker will ever reproduce that. The cone my vibrate, and you may destroy a perfectly good driver, but you will NOT generate a 5 Hz sound wave. For a start the cone will move but nothing will be generated. The Fs of a moving coil driver is essentially the lowest frequency it will generate, although it may make sound, but the cone will be breaking up and you will get frequency doubling. So if driver Fs is 23, and you feed it 15 Hz, you will likely hear 30 Hz, which is still very low and you may think you have generated 15 Hz, but you won't have.

Thanks for your feedback....

However, I dissagree with your conclusion and have been biting my tougne with you for a while Fist of all, I feel you were incredibly negative in my other posts saying I would over extend and damage the subs without doing any moddeling and told me I should be putting my cross over at 25 hz. Well , sir, you were dead wrong and I proved it with the WINISD cone excursion graph the cone excursion was only 23 mm at 1200 watts in a 6.2 cubic foot box. These subs have 29mm of one way cone travel and are well known to play single digit frequencies. I have personally seen/heard them that low. You have even admitted yourself that your not familar with these subs

Not to mention the person who builids these subs told me they would easily play down to DC, which is zero HZ.

From what I understand the Fs spec at 22 HZ is the sub in free air which is completley different than being in the box.

Im also well aware that the human ear does not hear anything below 20HZ and anything below 20 HZ will be "felt" as opposed to heard, so its not phyiscally possible to hear an actual 5 HZ or 10HZ for that matter.

You have also made negative assumptions in another post and told me the cvr d1004 was not a sub amp without asking me anying else. . You also assumed I knew nothing when it came to capping the wattage and line voltage to the sub. You kept mentioning I needed to EQ the signal despite me telling you multiple times that I am using a mini DSP for EQ and to set the low frequency limits at whatever they might be


With all due respect, it seems like you didnt even read what I have asked as your answer doesnt even begin to address what I have asked.

In the future, I'd appreciate it if we could stick to the specific questions I ask rather than making negative assumptions about my gear or knowledge level. Let's keep the discussion focused on the data."

 

[TLS Guy]

Thanks for your feedback....

However, I dissagree with your conclusion and have been biting my tougne with you for a while Fist of all, I feel you were incredibly negative in my other posts saying I would over extend and damage the subs without doing any moddeling and told me I should be putting my cross over at 25 hz. Well , sir, you were dead wrong and I proved it with the WINISD cone excursion graph the cone excursion was only 23 mm at 1200 watts in a 6.2 cubic foot box. These subs have 29mm of one way cone travel and are well known to play single digit frequencies. I have personally seen/heard them that low. You have even admitted yourself that your not familar with these subs

Not to mention the person who builids these subs told me they would easily play down to DC, which is zero HZ.

From what I understand the Fs spec at 22 HZ is the sub in free air which is completley different than being in the box.

Im also well aware that the human ear does not hear anything below 20HZ and anything below 20 HZ will be "felt" as opposed to heard, so its not phyiscally possible to hear an actual 5 HZ or 10HZ for that matter.

You have also made negative assumptions in another post and told me the cvr d1004 was not a sub amp without asking me anying else. . You also assumed I knew nothing when it came to capping the wattage and line voltage to the sub. You kept mentioning I needed to EQ the signal despite me telling you multiple times that I am using a mini DSP for EQ and to set the low frequency limits at whatever they might be


With all due respect, it seems like you didnt even read what I have asked as your answer doesnt even begin to address what I have asked.

In the future, I'd appreciate it if we could stick to the specific questions I ask rather than making negative assumptions about my gear or knowledge level. Let's keep the discussion focused on the data."

Look it up, it is well know that the Fs of the driver, is essentially its distortion free lower limit, or very close to it. You get into the arena where the models do not give you truth.

 

[Allen Vos]

Look it up, it is well know that the Fs of the driver, is essentially its distortion free lower limit, or very close to it. You get into the arena where the models do not give you truth.

Here is the definition of Fs.......

The Fs rating of a subwoofer driver is its free-air resonance frequency. It is the exact point in hertz (Hz) where the speaker cone moves easily on its own without a box.

I seen absolutley no mention of your claim.

In fact I simply googled this question.

"is Fs of a sub woofer driver essentially its distortion free lower limit"

answer

No. \(F_{s}\) (free-air resonant frequency) is the frequency at which a speaker's moving parts vibrate most naturally. It does not mark a "distortion-free" lower limit.




Again, you are not being helpful and I really dont wish to get into an argument over this.

If you want to be helpful in any way, just answer the actual question I had originally asked please

 

[TLS Guy]

Here is the definition of Fs.......

The Fs rating of a subwoofer driver is its free-air resonance frequency. It is the exact point in hertz (Hz) where the speaker cone moves easily on its own without a box.

I seen absolutley no mention of your claim.

In fact I simply googled this question.

"is Fs of a sub woofer driver essentially its distortion free lower limit"

answer

No. \(F_{s}\) (free-air resonant frequency) is the frequency at which a speaker's moving parts vibrate most naturally. It does not mark a "distortion-free" lower limit.




Again, you are not being helpful and I really dont wish to get into an argument over this.

If you want to be helpful in any way, just answer the actual question I had originally asked please

There is a lot of bad information out there on the NET. The free air resonance is actually close to the lower operating limit of the driver, and Box Pro clearly shows that when you do a design.

This is an article that gives you the true scoop.

I have over 70 years experience in designing and building speakers, and what I am telling you is the truth.

 

[Allen Vos]

There is a lot of bad information out there on the NET. The free air resonance is actually close to the lower operating limit of the driver, and Box Pro clearly shows that when you do a design.

This is an article that gives you the true scoop.

I have over 70 years experience in designing and building speakers, and what I am telling you is the truth.

Well sir, considering you were dead wrong on the speaker over extension at lower frequencies, and since you were extremely negative with every other aspect we spoke about. I find it very difficult to take anything you say seriously, Sorry but I think you missed the fact that others are running these subs down to single digit frequencies. This speaks volumes and its not possible all these people are wrong.

Also the fact that you would rather be negative and argue about this than answer any of my questions, means I really dont want your help any longer.

You also completly missed what I had asked.

Just a little FYI.

Talking with you has caused me nothing but confusion and has not helped in the least.

Take good care

 

[adk highlander]

So what is this signal supposed to prove for you? That you can fry your driver or you can hear like an elephant?

 

[Allen Vos]

So what is this signal supposed to prove for you? That you can fry your driver or you can hear like an elephant?

I feel your answer is completely irrellavant to the original question. Does anyone actaully read these posts before responding? lol

 

[adk highlander]

Yes. We do and you are asking an obtuse question. There is no reason or functional purpose to what you you 'think' you want to do. Dr. Mark while not having a bedside manor knows more than you so just listen or go somewhere else to ask your dumb questions.

 

[Allen Vos]

Yes. We do and you are asking an obtuse question. There is no reason or functional purpose to what you you 'think' you want to do. Dr. Mark while not having a bedside manor knows more than you so just listen or go somewhere else to ask your dumb questions.

Another difficult person lol
It was a very simple question.
Do any of you people realize your pride isint very helpful to anyone?
I'd tell you where to go but I dont think the Administrator would like that lol

 

[adk highlander]

Another difficult person lol
It was a very simple question.
I'd tell you where to go but I dont think the Administrator would like that lol

Considering I am a moderator on this forum, I welcome your so called simple questions so we can send you packing. No patience for stupid here. Go ask this on avs and see if you get more love. Good bye.

 

[Allen Vos]

Considering I am a moderator on this forum, I welcome your so called simple questions so we can send you packing. No patience for stupid here. Go ask this on avs and see if you get more love. Good bye.

So why cant you just read the original question and just be decent about it?

No offense, but Do you think telling someone their question is stupid, helps anyone?

 

[TLS Guy]

Well sir, considering you were dead wrong on the speaker over extension at lower frequencies, and since you were extremely negative with every other aspect we spoke about. I find it very difficult to take anything you say seriously, Sorry but I think you missed the fact that others are running these subs down to single digit frequencies. This speaks volumes and its not possible all these people are wrong.

Also the fact that you would rather be negative and argue about this than answer any of my questions, means I really dont want your help any longer.

You also completly missed what I had asked.

Just a little FYI.

Talking with you has caused me nothing but confusion and has not helped in the least.

Take good care

I am not confused. A speaker in free air is a spring and it has a resonant frequency just like a weight on a spring. In a closed box the air in the box is another spring. The balance between the two springs determines the frequency at which the bass rolls off. So the driver has to be forced to produce frequencies below that roll off. The roll off is second order and that is 12 db. per octave. So boost has to be placed below the F3 of the speaker enclosure dynamic. Once the driver reaches maximum extension, the driver has to be high passed by a filter to prevent damage. The model will show the frequency at which the driver has to be high passed. That is the essence of designing a sealed box sub. Which if you are patient I will model for you and the data will be presented in a clear form. That is how everybody who knows what they are doing designs a sealed sub.