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post #1 of 45 Old 05-16-2018, 02:30 PM - Thread Starter
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First impressions with my mini marty build

Hi people,

I've finally finished my mini marty build. It's UM15 with inuke 6000DSP. Today I listened to some music and watched some scenes from a few movies. I wasn't very impressed. I didn't really feel that earth shaking low frequencies. Also it feels a bit boomy. My settings on inuke:

Peak limiter: - 6 dBfs 4 Ohm (shows 803 watts)

High pass filter: 20 Hz, Butterworth 12 dB, gain 0

PEQ: - 4 dB, 20 Hz, HS12

When listening to music with a moderate level, lights on inuke don't always light up. Sometimes only the first led light up, rarely the second. Is that how it's supposed to be? The gain knob in front of inuke is set to 3 o'clock.

I don't have a measurement mic right now. I set the low pass filter on Sony str-dn1080 to 80 Hz. When playing some sine tones I noticed two things that seems to be weird:

1. The cone moves even with 5 Hz tone. Aren't the above mentioned settings supposed to stop the driver working at such low frequencies?

2. When I play an ascending sine sweep I can clearly hear that the sub is producing tones until 700 Hz. How is this possible while the low pass filter on my AVR is set to 80 Hz?

Thanks for your replies.
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post #2 of 45 Old 05-16-2018, 02:39 PM - Thread Starter
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Here is the audio clip I recorded using my Tascam portable recorder. I unplugged the main speakers and put the recorder just in front of the sub.

https://1drv.ms/u/s!Ap63xnOySIkcwTiGNOCQZrqsNMrb
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post #3 of 45 Old 05-16-2018, 02:41 PM
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Quote:
Originally Posted by Rairun View Post
Hi people,

I've finally finished my mini marty build. It's UM15 with inuke 6000DSP. Today I listened to some music and watched some scenes from a few movies. I wasn't very impressed. I didn't really feel that earth shaking low frequencies. Also it feels a bit boomy. My settings on inuke:

Peak limiter: - 6 dBfs 4 Ohm (shows 803 watts)

High pass filter: 20 Hz, Butterworth 12 dB, gain 0

PEQ: - 4 dB, 20 Hz, HS12

When listening to music with a moderate level, lights on inuke don't always light up. Sometimes only the first led light up, rarely the second. Is that how it's supposed to be? The gain knob in front of inuke is set to 3 o'clock.

I don't have a measurement mic right now. I set the low pass filter on Sony str-dn1080 to 80 Hz. When playing some sine tones I noticed two things that seems to be weird:

1. The cone moves even with 5 Hz tone. Aren't the above mentioned settings supposed to stop the driver working at such low frequencies?

2. When I play an ascending sine sweep I can clearly hear that the sub is producing tones until 700 Hz. How is this possible while the low pass filter on my AVR is set to 80 Hz?

Thanks for your replies.
I can maybe answer the second one. If you're using the built-in test-tone of your AVR, it's sending a signal out the LFE channel. The LFE goes straight to the sub without a low-pass-filter. Maybe some AVRs will filter the LFE output but mine doesn't. If you want to engage the filter, use a test tone for any of the other speakers that you have set to "small". The frequency content below your LPF setting (80Hz) will go to the subwoofer output, with declining amplitude as the frequency goes up.
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post #4 of 45 Old 05-16-2018, 03:11 PM - Thread Starter
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Thanks for the input.

I'm using test tones on YouTube.
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post #5 of 45 Old 05-16-2018, 04:38 PM
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The high pass and low pass are not brick walls. They are "filters" which means some stuff passes but at a lower volume. To keep it simple your high pass is telling things below 15hz to play 12db lower. So it's like a slope downwards instaed of a wall.

What is the tune of the mini Marty? Your high pass is effectively protecting a sub tuned to 15hz. I'd try it without that PEQ filter and trurn the outside knob about 9 clicks (you shouldn't go past 15 clicks). You can also set a low pass in the inuke if you wish maybe set it at 250hz and do a Butterworth 12 or 24 or whatever you like. In the end your receiver and it's room correction software should help.
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post #6 of 45 Old 05-16-2018, 06:58 PM
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Quote:
Originally Posted by corradizo View Post
What is the tune of the mini Marty?

Mini martys are tuned to 17hz.


Rairun, I'm also running a Mini marty, except I have a UM18. I can tell you that music will not be as impressive as you expected. I went through this as well. The UM18 and probably the 15 as well, in a mini marty, are tuned so low, they miss a lot of the bass commonly heard in music. This is why I'm building a dual VBSS setup with the PA460s. They are much better at music bass frequencies than the UM18s. The UM18 in a mini marty really is much more geared towards home theater applications where you're reproducing frequencies 30hz and down.... which is also below the range for most music.
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post #7 of 45 Old 05-16-2018, 07:25 PM
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Quote:
Originally Posted by Rairun View Post
Hi people,

I've finally finished my mini marty build. It's UM15 with inuke 6000DSP. Today I listened to some music and watched some scenes from a few movies. I wasn't very impressed. I didn't really feel that earth shaking low frequencies. Also it feels a bit boomy. My settings on inuke:

Peak limiter: - 6 dBfs 4 Ohm (shows 803 watts)

High pass filter: 20 Hz, Butterworth 12 dB, gain 0

PEQ: - 4 dB, 20 Hz, HS12

When listening to music with a moderate level, lights on inuke don't always light up. Sometimes only the first led light up, rarely the second. Is that how it's supposed to be? The gain knob in front of inuke is set to 3 o'clock.
The "gain" knob on the front of the iNukes is an attenuation knob - It allows more/less signal from your AVR on the input into which it is plugged. Have you adjusted the gain within the software/front panel?

Quote:
Originally Posted by Rairun
I don't have a measurement mic right now. I set the low pass filter on Sony str-dn1080 to 80 Hz. When playing some sine tones I noticed two things that seems to be weird:

1. The cone moves even with 5 Hz tone. Aren't the above mentioned settings supposed to stop the driver working at such low frequencies?
As others have already mentioned, crossovers aren't brick walls. You would see some reaction from the sub above/below the crossovers.

Quote:
Originally Posted by Rairun
2. When I play an ascending sine sweep I can clearly hear that the sub is producing tones until 700 Hz. How is this possible while the low pass filter on my AVR is set to 80 Hz?

Thanks for your replies.
You may, but that seems high. What are your mains crossed over at?

When I measure my subs I do the following (in this order):

Disable Audyssey (or YPAO, or whatever DSP your AVR has)
Set L/R crosovers as high as possible
Unhook the L/R speakers
Take measurement
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post #8 of 45 Old 05-16-2018, 07:41 PM
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I think your highpass is correct (-6db HS12 is 15hz not -4db) except for whatever you put in the hs12 as a negative number. In your case, -4db. You need to add +4db in the crossover section to bring the level back up....or crank the external knob some more.
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post #9 of 45 Old 05-16-2018, 11:35 PM - Thread Starter
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[QUOTE=smcmillan2;56199748]
Quote:
Originally Posted by Rairun View Post

Quote:
Originally Posted by Rairun
2. When I play an ascending sine sweep I can clearly hear that the sub is producing tones until 700 Hz. How is this possible while the low pass filter on my AVR is set to 80 Hz?

Thanks for your replies.
You may, but that seems high. What are your mains crossed over at?

When I measure my subs I do the following (in this order):

Disable Audyssey (or YPAO, or whatever DSP your AVR has)
Set L/R crosovers as high as possible
Unhook the L/R speakers
Take measurement
As I said, the low pass on AVR is set to 80 Hz, so the mains are crossovered at 80.

I never use Audyssey or any similar features on AVRs.

And the mains are already unhooked when testing the sub with an ascending sine sweep. I know that filters don't cut everything just outside the set frequency but I don't think my sub is supposed to produce a 700 Hz tone while it's crossedover at 80 Hz. I don't know what's going on.
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post #10 of 45 Old 05-17-2018, 08:17 AM
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Quote:
Originally Posted by corradizo View Post
I'd try it without that PEQ filter and trurn the outside knob about 9 clicks (you shouldn't go past 15 clicks).
Are you referring to the attenuator knobs on the front? If so why 9 clicks and no more than 15? I run mine as far right as they go
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post #11 of 45 Old 05-17-2018, 08:40 AM
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Originally Posted by Acrjoey View Post
Are you referring to the attenuator knobs on the front? If so why 9 clicks and no more than 15? I run mine as far right as they go

@Shreds has a great thread on the inuke 6000dsp. My understanding is anything past 15 clicks leads to higher levels of distortion/clipping.

9 clicks is an arbitrary number. There is a better way to do this (let's see if I remember) where you disconnect your speakers (cuz otherwise you'll need ear protection) and subs from their respective amps. You play a track through your BluRay player (so you are using your actual signal chain an not Rew via HDMI), like Edge if Tomorrow opening scene and you set your avr sub trim at 0 and set your AVR at 0mv (or the loudest you'll ever go, ever) and put the inuke around 9 or 10 clicks. You play the clip while watching the input on your inuke software. If it jumps to clipping, turn the inuke knob back down until it doesn't clip anymore. That represents your max inuke clicks based on the set AVR trim for the sub. Your should not go over these setting or risk clipping. Following this, you can set your sub trim lower to properly match your mains.
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post #12 of 45 Old 05-17-2018, 09:20 AM - Thread Starter
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Thanks! What about hearing up to 700 Hz from the sub?
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post #13 of 45 Old 05-17-2018, 09:44 AM
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Quote:
Originally Posted by Rairun View Post
Thanks! What about hearing up to 700 Hz from the sub?
How do you know you're hearing frequencies up to 700 without a mic? You're recording sounded about like what I would expect. I didn't hear anything that sounded as high as 700Hz. Below is a 700hz link for reference. You are correct that it would be quite high for a sub.


Also, someone correct me if I am wrong, but assuming a 12db/octave crossover at 80Hz, 640Hz should be -36db lower. This means if your 80Hz volume is 90db, 640 would still be audible, though just barely since it is approaching the noise floor of most untreated rooms.
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post #14 of 45 Old 05-17-2018, 09:51 AM - Thread Starter
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Originally Posted by Rairun View Post
Thanks! What about hearing up to 700 Hz from the sub?
How do you know you're hearing frequencies up to 700 without a mic? You're recording sounded about like what I would expect. I didn't hear anything that sounded as high as 700Hz. Below is a 700hz link for reference. You are correct that it would be quite high for a sub.


Also, someone correct me if I am wrong, but assuming a 12db/octave crossover at 80Hz, 640Hz should be -36db lower. This means if your 80Hz volume is 90db, 640 would still be audible, though just barely since it is approaching the noise floor of most untreated rooms.
I unhooked the main speakers. Played a test tone starting from 5 Hz going up to 20 kHz. When the frequency of the tone passes 700 Hz I can't hear anything anymore. And it's still clearly audible, nor very subtle. But I was thinking that I shouldn't be hearing such high frequencies on a subwoofer.
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post #15 of 45 Old 05-17-2018, 12:12 PM
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Quote:
Originally Posted by Rairun View Post
Hi people,

I've finally finished my mini marty build. It's UM15 with inuke 6000DSP. Today I listened to some music and watched some scenes from a few movies. I wasn't very impressed. I didn't really feel that earth shaking low frequencies. Also it feels a bit boomy. My settings on inuke:

Peak limiter: - 6 dBfs 4 Ohm (shows 803 watts)

High pass filter: 20 Hz, Butterworth 12 dB, gain 0

PEQ: - 4 dB, 20 Hz, HS12

When listening to music with a moderate level, lights on inuke don't always light up. Sometimes only the first led light up, rarely the second. Is that how it's supposed to be? The gain knob in front of inuke is set to 3 o'clock.

I don't have a measurement mic right now. I set the low pass filter on Sony str-dn1080 to 80 Hz. When playing some sine tones I noticed two things that seems to be weird:

1. The cone moves even with 5 Hz tone. Aren't the above mentioned settings supposed to stop the driver working at such low frequencies?

2. When I play an ascending sine sweep I can clearly hear that the sub is producing tones until 700 Hz. How is this possible while the low pass filter on my AVR is set to 80 Hz?

Thanks for your replies.

"Boomy" is from your room. If you can't measure, do the Sub Crawl. If only one light is lighting, you have room to turn up the gain knobs. Experiment. Play Skater Boi, and adjust the gains until the red light barely blinks on the bass drops.

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post #16 of 45 Old 05-17-2018, 09:17 PM
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Originally Posted by corradizo View Post
disconnect your speakers (cuz otherwise you'll need ear protection) and subs from their respective amps. You play a track through your BluRay player (so you are using your actual signal chain an not Rew via HDMI), like Edge if Tomorrow opening scene and you set your avr sub trim at 0 and set your AVR at 0mv (or the loudest you'll ever go, ever) and put the inuke around 9 or 10 clicks. You play the clip while watching the input on your inuke software. If it jumps to clipping, turn the inuke knob back down until it doesn't clip anymore. That represents your max inuke clicks based on the set AVR trim for the sub. Your should not go over these setting or risk clipping. Following this, you can set your sub trim lower to properly match your mains.
This is a good trick to get you in the ballpark of where you want to be but keep in mind that maximum output level for an amplifier will change when a dynamic load is connected. Most amps are current limited especially when running at impedance minimums. The ultimate test for your sub system is with real world, worst case, source material while monitoring amp clip lights and driver excursion. This will teach you the most about the limits of your system.

To the OP, you're completely in the dark until you get a measurement rig and the advice we can give you is extremely limited until we can see graphs. I always use the analogy of imagine building a house by "eyeballing" everything instead of using a tape measure.
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post #17 of 45 Old 05-17-2018, 11:34 PM
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Originally Posted by corradizo View Post
@Shreds has a great thread on the inuke 6000dsp. My understanding is anything past 15 clicks leads to higher levels of distortion/clipping.

9 clicks is an arbitrary number. There is a better way to do this (let's see if I remember) where you disconnect your speakers (cuz otherwise you'll need ear protection) and subs from their respective amps. You play a track through your BluRay player (so you are using your actual signal chain an not Rew via HDMI), like Edge if Tomorrow opening scene and you set your avr sub trim at 0 and set your AVR at 0mv (or the loudest you'll ever go, ever) and put the inuke around 9 or 10 clicks. You play the clip while watching the input on your inuke software. If it jumps to clipping, turn the inuke knob back down until it doesn't clip anymore. That represents your max inuke clicks based on the set AVR trim for the sub. Your should not go over these setting or risk clipping. Following this, you can set your sub trim lower to properly match your mains.
I guess everyone's settup is different. I many try this later but my setup has knobs set all the way right across NEVER gets to zero I usually watch movies at -24 and blast music at -10 if I want to hear it in my entire home. These settings I have never seen the red clip light and RARELY see the 3rd clip light. I am not against lowering the knobs a few clicks if it lowers distortion and just lowering all speakers except the subs to compensate lack of total volume. I mean turn knobs a few clicks left while leaving subs in avr at zero then lowering all channels except sub -4 each. I did not realize having the inukes gain knobs at 100% caused disortion. I have just always ran my pro amps with the atuimators all the way right. Then reduced sub trim in avr.
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post #18 of 45 Old 05-18-2018, 03:01 AM - Thread Starter
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I will make measurements in one week and share with you.

Btw I haven't lined the walls inside the cab. I don't know if it would make a noticable difference. The cab is very well braced.
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post #19 of 45 Old 05-18-2018, 04:34 AM
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Quote:
Originally Posted by Shreds View Post
This is a good trick to get you in the ballpark of where you want to be but keep in mind that maximum output level for an amplifier will change when a dynamic load is connected. Most amps are current limited especially when running at impedance minimums. The ultimate test for your sub system is with real world, worst case, source material while monitoring amp clip lights and driver excursion. This will teach you the most about the limits of your system.

To the OP, you're completely in the dark until you get a measurement rig and the advice we can give you is extremely limited until we can see graphs. I always use the analogy of imagine building a house by "eyeballing" everything instead of using a tape measure.


I recommended using a dynamic load. Edge of Tommorow is a movie with a very demanding opening scene.
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post #20 of 45 Old 05-18-2018, 01:20 PM
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Quote:
Originally Posted by Acrjoey View Post
I guess everyone's settup is different. I many try this later but my setup has knobs set all the way right across NEVER gets to zero I usually watch movies at -24 and blast music at -10 if I want to hear it in my entire home. These settings I have never seen the red clip light and RARELY see the 3rd clip light. I am not against lowering the knobs a few clicks if it lowers distortion and just lowering all speakers except the subs to compensate lack of total volume. I mean turn knobs a few clicks left while leaving subs in avr at zero then lowering all channels except sub -4 each. I did not realize having the inukes gain knobs at 100% caused disortion. I have just always ran my pro amps with the atuimators all the way right. Then reduced sub trim in avr.

Only the red light is a "clip" light. The other lights are output level indicators. You are only using about a quarter of the amps power, so you have plenty of headroom left.

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post #21 of 45 Old 05-19-2018, 01:29 AM
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You are only using about a quarter of the amps power, so you have plenty of headroom left.

That's what I told him.


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...If only one light is lighting, you have room to turn up the gain knobs...

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post #22 of 45 Old 05-19-2018, 04:55 AM
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A lot of people get confused with the lights on inukes. I myself did.

Interesting way to set a sub with skater boi lol, never heard that. How low does it go?

- 6 BA CR6 array center channel, QSC AD-S82 L/R, 4 jbl 8330a surr , 8 jbl 12" subs w/Inuke 6000. JVC rs420, Denon x4000, Sony x800 -
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post #23 of 45 Old 05-19-2018, 11:35 AM
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A lot of people get confused with the lights on inukes. I myself did.

Interesting way to set a sub with skater boi lol, never heard that. How low does it go?

Teehee


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post #24 of 45 Old 05-19-2018, 12:13 PM
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Originally Posted by corradizo View Post
I recommended using a dynamic load. Edge of Tommorow is a movie with a very demanding opening scene.
I wasn't referring to source material. I meant a dynamic load for the amplifier (a large subwoofer coil with inductance) vs. no load (nothing connected). The amplifier will behave significantly different with a dynamic load especially when pushed with strong signal around impedance minimums.

As far as using the opening to EOT as a worst case scenario for the amp to drive the minimarty:


Figuring on no AVR rolloff adding to the signal chain (which is unlikely) this would be ~the frequency response that the amp would be responsible for reproducing:


So by the time that you got to the 15Hz tone, you'll be around 5dB down and at the10Hz tone you'll be around 11dB down. Once you consider the impedance curve for the UM15 in the mini cab:


The 20Hz tone would be the only real challenge for the amplifier in that opening scene as the impedance drops to about 4.5ohms. The 15Hz and 10Hz tone are dropped off significantly in signal and are at a higher impedance. The tones above 20Hz are at a higher impedance so are not as challenging to the amp (shorter frequency wavelengths -less demanding as well).

Square waves are tough but this is more of a demanding scene for a sealed system IMO. There are plenty of scenes with strong bass centered at 20Hz out there that you can test the amp's behavior with stronger transients.
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post #25 of 45 Old 05-19-2018, 12:29 PM
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Quote:
Originally Posted by Acrjoey View Post
I did not realize having the inukes gain knobs at 100% caused disortion. I have just always ran my pro amps with the atuimators all the way right. Then reduced sub trim in avr.
This is not necessarily true. It depends on your gain stages and how much signal you feed an amplifier with. Many AVR's these days are rated to put ~1.2V on the sub out. Figuring this in my tests the NU6k reached maximum output with the knob up 15 clicks. If your signal chain fed the amplifier 0.7V for example, you would need to turn the knobs up more than that or max out the knobs and move to the DSP section to boost the signal in the digital domain to reach maximum output.

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Originally Posted by zeus33 View Post
You are only using about a quarter of the amps power, so you have plenty of headroom left.
The amp that I tested was close to this but not exact so keep in mind that you are still able to reach this amp's maximum clean output level with the 3rd light. Not a big deal, just something to be aware of:

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Originally Posted by Shreds View Post
The front signal LED's... from the 1st light to where the 2nd lights up is 12dB. From the 2nd to the 3rd is 5dB and from the 3rd to the clip light is 5dB. The clip lights are only accurate at 7.5Hz and below. Above that frequency, the amp goes into clip without the red light coming on. At 100Hz, the clip light is off by 1.5dB. By the time the clip light comes on the amp is already into about 5-10% THD depending on the frequency. This is with no limiter engaged.
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post #26 of 45 Old 05-19-2018, 01:01 PM
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Originally Posted by trilkb View Post
Interesting way to set a sub with skater boi lol, never heard that. How low does it go?
No offense to anyone but skater boi is not that good of a mix IMO:


If you like Avril, check this one... better mix:

Hello Kitty:




Obviously adjusting your sub gains so that maximum amp output is reached with pop music is going to be devastating to your system when something with hot bass is put in so remember to turn the gain back down with other source material. This is because pop music typically mixes the low end's signal anemic.
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Last edited by Shreds; 05-19-2018 at 01:05 PM.
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post #27 of 45 Old 05-19-2018, 06:36 PM
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Quote:
Originally Posted by Shreds View Post
I wasn't referring to source material. I meant a dynamic load for the amplifier (a large subwoofer coil with inductance) vs. no load (nothing connected). The amplifier will behave significantly different with a dynamic load especially when pushed with strong signal around impedance minimums.

As far as using the opening to EOT as a worst case scenario for the amp to drive the minimarty:


Figuring on no AVR rolloff adding to the signal chain (which is unlikely) this would be ~the frequency response that the amp would be responsible for reproducing:


So by the time that you got to the 15Hz tone, you'll be around 5dB down and at the10Hz tone you'll be around 11dB down. Once you consider the impedance curve for the UM15 in the mini cab:


The 20Hz tone would be the only real challenge for the amplifier in that opening scene as the impedance drops to about 4.5ohms. The 15Hz and 10Hz tone are dropped off significantly in signal and are at a higher impedance. The tones above 20Hz are at a higher impedance so are not as challenging to the amp (shorter frequency wavelengths -less demanding as well).

Square waves are tough but this is more of a demanding scene for a sealed system IMO. There are plenty of scenes with strong bass centered at 20Hz out there that you can test the amp's behavior with stronger transients.


My intention was to help figure out when the input on the inuke would clip. Does the knob control the input or the output? Or... Am I totally confused?
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post #28 of 45 Old 05-19-2018, 07:21 PM
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Originally Posted by corradizo View Post
My intention was to help figure out when the input on the inuke would clip. Does the knob control the input or the output? Or... Am I totally confused?
To my (admittedly limited on the subject) knowledge, the "gain" knobs on the front of the iNukes attenuate the input signal, and the gain in the software/via front control LED control the output signal.
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post #29 of 45 Old 05-19-2018, 07:32 PM
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First impressions with my mini marty build

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Originally Posted by smcmillan2 View Post
To my (admittedly limited on the subject) knowledge, the "gain" knobs on the front of the iNukes attenuate the input signal, and the gain in the software/via front control LED control the output signal.


Right. This is my understanding too, which is why I recommend the outside knob and the software input be monitored.
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post #30 of 45 Old 05-20-2018, 01:21 AM - Thread Starter
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Nice discussion 🙂 Meanwhile I'd like to drop a few more questions:

1. My AVR has an option under the HDMI settings called "Subwoofer Level" and the choices are Auto, 0 dB or +10 dB. Additionally, there's another setting page that let you set the level of each connected speaker in 0.5 dB increments. So, when the signal feeding the amp is too low, which setting I should use to increase it? HDMI or Level setting on the AVR or the knob in front of Inuke amp?

2. When playing a bass heavy material, I can feel almost no air coming out of the ports. (They are not blocked) I can see that the woofer moves a lot. I tought there would be so much air pushed from the ports. Is this the way it's supposed to be?

3. I read that with ported subs it's very important to have a high pass filter on the signal chain in order to protect the woofer (from over excursion?). Right now with the aforementioned settings I use, the woofer moves a lot when fed with a 5 Hz sine tone. Is that normal? (Yes, I know that filters don't cut everything below a certain point, but still...)

Thanks again.

Last edited by Rairun; 05-20-2018 at 01:50 AM.
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