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Discussion Starter #1 (Edited)
Finally got a DSP and it's been a learning experience. A few questions for those with expertise with this DSP:

1. The input visual guideline, when selecting the voltage, can't go into the red. That said, do you guys maximize the yellow lines, or keep it Midway? The difference between 4v and 1 step down is 1 tiny sliver of yellow (never entering into red), so I wondered if it was worth it.

2. When output is maximized (0db), is it better to lower the output to balance the tweeters with the mids, or is it best done by lowering gain at the amp?

3. At times, there are songs that seem to have weak bass i.e. rock / metal, yet any EDM songs, electronic, rap, sounds wildly fuller. Is this due to crossovers? And if so, do you guys run different presets for genres of music or is there a middle ground?

Thanks in advance!
 

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I've been using a twik88 for about 4 months now.
1- not sure, I didn't change the input settings.
2- I do some of both. if I get to where I'm cutting the output on the twk88 a lot, more than 10db, I cut the amp a little bit.
3- I havent gotten to that level yet. I've been lucky to get one setting that works for most tracks. What I have been doing lately is using the EQ on the HU. I've found 2db +/- on the mid range frequencies gets it done. From what I can tell you cannot cut 2 db at lets say 500hz without jacking up your channel matching. I think that's called summing and the 88 doesn't do it without choosing one channel or the other. This is why I use the HU. I'm using 2 channels from the HU into the 88 so when I cut 2db at 400hz it gets me in the ball park.
 

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Discussion Starter #3
I've been experimenting with it a lot this week. So far it seems a mix of gains lowering and output changes on the 88 give me the best performance for output vs noise. It's very interesting that cutting just one doesn't do the trick by itself. Balancing act it seems.

Thanks for the feedback, it's helpful :)
 

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I don't have direct experience with the twk so can't really comment on 1 & 2.

But for 3:
This is very likely due to just different recordings being produced & mixed differently with differing amounts of emphasis on certain areas of the audible spectrum. A different preset on the DSP is a good option or adjustments on the headunit eq can work too.
 

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I managed to install this over the weekend. I just need to get the input sensitivity correct. My HU puts out 5v, the DSP input sensitivity is at 7.1, which is pretty high, it should be lower and yet I've had to crank up the gain on my Rockford Fosgate T1000x5 AD. So I'm doing something wrong somewhere. I think I'll stick my DD1 on it and see what's going on
 

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I used a CRO to check max undistorted output from head unit , this will be max volume , never go past this , this with a -5db track for mid and upper frequencies and -10db track for the subwoofer.
With the head unit outputting this max unclipped signal I adjust input scaling so as only in the yellow , no red , not even a tiny bit , so you want the maximum you can get before it's in the red.
Adjust midwoofers and sub amp gain using the CRO for max unclipped output while still feeding the max unclipped signal from the head unit.

I set my amp tweeter gain on minimum , I still needed to reduce this another 10db in the TWK-88 to match the midwoofers , keeping the amp tweeter gain on minimum will give the lowest noise floor , so this is the preferred setup.

I use the Sub output as well from the head unit so I can adjust the bass level as needed but in saying that I find I very rarely need to adjust it , but it's nice to have.
 

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I used a CRO to check max undistorted output from head unit , this will be max volume , never go past this , this with a -5db track for mid and upper frequencies and -10db track for the subwoofer.
With the head unit outputting this max unclipped signal I adjust input scaling so as only in the yellow , no red , not even a tiny bit , so you want the maximum you can get before it's in the red.
Adjust midwoofers and sub amp gain using the CRO for max unclipped output while still feeding the max unclipped signal from the head unit.

I set my amp tweeter gain on minimum , I still needed to reduce this another 10db in the TWK-88 to match the midwoofers , keeping the amp tweeter gain on minimum will give the lowest noise floor , so this is the preferred setup.

I use the Sub output as well from the head unit so I can adjust the bass level as needed but in saying that I find I very rarely need to adjust it , but it's nice to have.
Thanks mrexcitement. I'm trying to work out what you mean by a CRO? I'm assuming its an o-scope? Prior to installing the TwK, it was pretty straightforward, I'd run 3 sets of RCA's from the HU to the 5 channel amp, stick the DD1 probes into the speaker outputs, play both a 1k and a 40hz tones at 0db to establish the max unclipped volume. Once that is done, I would play a 1k -5db tone for the mids/highs and set the gain, then move onto the sub channel and play a 40hz tone @ -10db for the sub channel and then I'm done. Pretty straightforward, and because the HU puts out a strong 5v output, the gain pots only need to be moved about 1/4 (if that) of the way.

Adding the TwK though seems to have caused me a dilemma or I'm doing something wrong for two reasons, firstly I have the input sensitivity set to 7.1, which is the highest setting on the sensitivity, so I need to bring that down. This high setting has then led to point 2, which is that the gain is almost 3/4 of the way turned. This has then led to very weak sub bass and hissing on the signal path, so I think midstream somewhere something has gone wrong, leading to an unclipped but weak signal being passed to the amplifier.

My question is, on the TwK, are you starting from the lowest setting and working your way up, as in 240mv and up? Or are you going the other way and starting at 7.1v and working your way down? I spoke to someone from JL and he said that I should start from the top and work down. So basically, the lower the input number, the more sensitive it will be and thus the less I will need to turn the gain and thus reducing the floor noise.
 

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Thanks mrexcitement. I'm trying to work out what you mean by a CRO? I'm assuming its an o-scope? Prior to installing the TwK, it was pretty straightforward, I'd run 3 sets of RCA's from the HU to the 5 channel amp, stick the DD1 probes into the speaker outputs, play both a 1k and a 40hz tones at 0db to establish the max unclipped volume. Once that is done, I would play a 1k -5db tone for the mids/highs and set the gain, then move onto the sub channel and play a 40hz tone @ -10db for the sub channel and then I'm done. Pretty straightforward, and because the HU puts out a strong 5v output, the gain pots only need to be moved about 1/4 (if that) of the way.

Adding the TwK though seems to have caused me a dilemma or I'm doing something wrong for two reasons, firstly I have the input sensitivity set to 7.1, which is the highest setting on the sensitivity, so I need to bring that down. This high setting has then led to point 2, which is that the gain is almost 3/4 of the way turned. This has then led to very weak sub bass and hissing on the signal path, so I think midstream somewhere something has gone wrong, leading to an unclipped but weak signal being passed to the amplifier.

My question is, on the TwK, are you starting from the lowest setting and working your way up, as in 240mv and up? Or are you going the other way and starting at 7.1v and working your way down? I spoke to someone from JL and he said that I should start from the top and work down. So basically, the lower the input number, the more sensitive it will be and thus the less I will need to turn the gain and thus reducing the floor noise.

What head unit are you using, what's the pre-out strength and what input sensitivity setting do you have it on in the TwK? Thanks
 

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Thanks mrexcitement. I'm trying to work out what you mean by a CRO? I'm assuming its an o-scope? Prior to installing the TwK, it was pretty straightforward, I'd run 3 sets of RCA's from the HU to the 5 channel amp, stick the DD1 probes into the speaker outputs, play both a 1k and a 40hz tones at 0db to establish the max unclipped volume. Once that is done, I would play a 1k -5db tone for the mids/highs and set the gain, then move onto the sub channel and play a 40hz tone @ -10db for the sub channel and then I'm done. Pretty straightforward, and because the HU puts out a strong 5v output, the gain pots only need to be moved about 1/4 (if that) of the way.

Adding the TwK though seems to have caused me a dilemma or I'm doing something wrong for two reasons, firstly I have the input sensitivity set to 7.1, which is the highest setting on the sensitivity, so I need to bring that down. This high setting has then led to point 2, which is that the gain is almost 3/4 of the way turned. This has then led to very weak sub bass and hissing on the signal path, so I think midstream somewhere something has gone wrong, leading to an unclipped but weak signal being passed to the amplifier.

My question is, on the TwK, are you starting from the lowest setting and working your way up, as in 240mv and up? Or are you going the other way and starting at 7.1v and working your way down? I spoke to someone from JL and he said that I should start from the top and work down. So basically, the lower the input number, the more sensitive it will be and thus the less I will need to turn the gain and thus reducing the floor noise.

What head unit are you using, what's the pre-out strength and what input sensitivity setting do you have it on in the TwK? Thanks
 

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At 3.: Set it to a target curve. In 99.99999% of all times missing bass in a record is just that. A record without bass. Just compare "And justice for all..." from Metallica to any EDM record and you know what i mean. No DSP setup on this earth will make that Metallica record have any bass and still sound good with any other record. ;)
 

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Yes oscilloscope , sorry they used to be also known as CRO (cathode ray oscilloscope)

Your dd1 will do the same job and can check RCA levels as well as amp output levels.

Have you established your maximum unclipped output from your head unit using a -5db test tone , check all your RCA outputs , as this will be your reference when setting all DSP/amp gain settings , my max volume is 35 and my max unclipped is 31.

Sounds like you are loosing signal level through the TWK by incorrect input gain setting , yes the 7.1V input setting means it needs 7.1V from the head unit to achieve 0db output on the TWK , if your head unit is not outputting this level you won't be getting the max output from the DSP

I think the recommendation from JL is for safety as highest to lowest goes from minimum gain to max gain , just keep going lower until your in the red and come back one step and check your only maxing in the yellow and not the red , I use a -5db track for this.

While doing this setting also make sure the TWK outputs are at 0db and plug your dd1 into the output of the TWK , this will also allow you to see when the input voltage setting has gone too low as there will be distortion , again your after the lowest input volts setting on the TWK to achieve max output with no distortion.

Make sure the head units subwoofer level is at max (mine is +15) and the TWK outputs set to 0db except for the tweeter , start with -15db , I ended up at -10db to match the midwoofers.

I think I ended up around the 4V input sensitivity setting on the TWK (at work can't check until later) Alpine CDE-196DAB.

The tweeter amp gain should be on minimum as this will give the lowest noise floor.

Now set the subwoofer and midwoofers amp gains to max unclipped output while playing a -5db for midwoofers and -10db for subwoofer.

Now you will most likely have too much sub and that's where you adjust it in the head unit subwoofer level for personal preference , I ended up at +11 for a good bass heavy setup ( I'm a bass head )

To achieve the lowest noise floor you are trying to maximize the signal output from head unit to DSP to amp so the amps are receiving the maximum unclipped signal this will ensure your using the minimum gain necessary on the amps , the lower the input volts to the amp the higher the amp gain needs to be and the noise floor will be higher.

Use your dd1 to check at each stage eg head unit outputs , DSP outputs and amp outputs.

Also if you find you end up with the gains on the amps set higher than before the TWK was fitted , it shows that you are loosing signal level through the TWK and need to adjust it , I never had that reference as I installed the system with the DSP all at once.

Good luck

Cheers

David
 

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Yes oscilloscope , sorry they used to be also known as CRO (cathode ray oscilloscope)

Your dd1 will do the same job and can check RCA levels as well as amp output levels.

Have you established your maximum unclipped output from your head unit using a -5db test tone , check all your RCA outputs , as this will be your reference when setting all DSP/amp gain settings , my max volume is 35 and my max unclipped is 31.

Sounds like you are loosing signal level through the TWK by incorrect input gain setting , yes the 7.1V input setting means it needs 7.1V from the head unit to achieve 0db output on the TWK , if your head unit is not outputting this level you won't be getting the max output from the DSP

I think the recommendation from JL is for safety as highest to lowest goes from minimum gain to max gain , just keep going lower until your in the red and come back one step and check your only maxing in the yellow and not the red , I use a -5db track for this.

While doing this setting also make sure the TWK outputs are at 0db and plug your dd1 into the output of the TWK , this will also allow you to see when the input voltage setting has gone too low as there will be distortion , again your after the lowest input volts setting on the TWK to achieve max output with no distortion.

Make sure the head units subwoofer level is at max (mine is +15) and the TWK outputs set to 0db except for the tweeter , start with -15db , I ended up at -10db to match the midwoofers.

I think I ended up around the 4V input sensitivity setting on the TWK (at work can't check until later) Alpine CDE-196DAB.

The tweeter amp gain should be on minimum as this will give the lowest noise floor.

Now set the subwoofer and midwoofers amp gains to max unclipped output while playing a -5db for midwoofers and -10db for subwoofer.

Now you will most likely have too much sub and that's where you adjust it in the head unit subwoofer level for personal preference , I ended up at +11 for a good bass heavy setup ( I'm a bass head )

To achieve the lowest noise floor you are trying to maximize the signal output from head unit to DSP to amp so the amps are receiving the maximum unclipped signal this will ensure your using the minimum gain necessary on the amps , the lower the input volts to the amp the higher the amp gain needs to be and the noise floor will be higher.

Use your dd1 to check at each stage eg head unit outputs , DSP outputs and amp outputs.

Also if you find you end up with the gains on the amps set higher than before the TWK was fitted , it shows that you are loosing signal level through the TWK and need to adjust it , I never had that reference as I installed the system with the DSP all at once.

Good luck

Cheers

David
Hi, so I managed to reset the gains today, took a while. Managed to settle on 4v input at volume 46/50. The bars did show slightly red, however the DD1 didn’t show any clipping until I raised the volume to 47 or deviated from the 4v input either up or down. It would either lose signal, not detect the frequency or show distortion and only settled on 4v at volume 46. I tested this on both the outputs of the TwK and the outputs of the amp. The bass is far stronger now and the music is more dynamic. Prior to that it was weak. I am running semi-active on the front. The mids/tweets are highpassed at 300hz, the midbass are bandpassed between 80-300hz and the sub is low passed at 60hz. I have yet to do the time alignment and EQ. Even though the max volume is 46, I’ll probably never listen at that volume. I usually listen at 30. Now the fun begins with time alignment and EQ. I have the Audifrog Mic and accompanying notes etc.
 

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Looks like you have set it up properly now.

I used Jazzi's tuning guide with his house curve for tuning and I think my system sounds awesome but the house curve can be a personal preference.
 

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I know there are skeptics but the DD1 has been valuable to me and has always given me accurate results. I have an oscope too, one of those handheld, it's a Liumy, but the resolution isn't great. If I didn't have the DSP I might have purchased the CC1 for setting up the crossovers.
 
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