Crown XTi 4002 & Cerwin Vega CVP 2153

[DidrikHansen]

Hello,

I currently own a pair of Cerwin Vega CVP 2153 aswell as a XTI 4002 power amplifier.

I am using this setup in my living room.

The signal is fed to the amplifier this way: PC - (USB) - Cambridge DACmagic 100 - (Phono) - NAD T748 - (pre-out-phono/xlr) - Crown XTI 4002.

This setup works great, although i'm looking into upgrading to a XTI 6002 or I-TECH 6000 amplifier. I have not made any adjustments considering EQ at this point because i'm not that familiar with equalization in general. What i want to do in the first place, is to eliminate clipping. I have tried setting the limiter settings to -0.1dDBFS with default 0.1 attack and 1.0 release times, but the amplifier still indicates clipping. I do not need to limit the power in any way but I don't want to damage my speakers by clipping them.

I would also like to know if I should filter frequencies below/above 37hz/20khz since the speakers' are "unable" to play frequencies below/above those marks?

Any suggestions considering basic EQ configuration to improve sound quality is also welcome.


( Cerwin Vega CVP 2153 )
- Frequency Response: 37 Hz - 20 kHz / 134 dB SPL
- Power Capacity: 1000W RMS / 2000W Program / 4000W Peak
- Recommended Power: 1500 w - 2000 w
- Sensitivity (1w/1m): 101 dB
- Nominal Impedance: 4 ohms


I appreciate any help i might get.

 

[18Hurts]

I have an XTi 1002 and some thoughts

Set mine up about the same as yours but with -2.5dB for the limiter. The amp is used in my garage and the adjustable limiter prevents blown breakers (and visits from the police) Once the limiter is engaged, that red light is now indicating the limiter is kicking in. The amp is not clipping at that point. Mild flashes of the limiter is fine, if the light is constantly flashing--turn it down a touch to prevent cooking voice coils.

I would adjust the high pass filter to around 35Hz to prevent anything below that from hammering the woofers. That saves on power also, why waste power with the frequencies the woofers are not able to produce.

I think those Vegas are 4 ohms so you'll get 1,200 watts from the XTi 4002. The only thing an XTi 6002 will give you is blown speakers, blown breakers and that sort of thing. Assuming no power compression, 2000 watts would give you 2dB more output. You might notice it louder...but most likely it will sound about the same.

Your setup looks like it is for a house? If so, what you need is some subwoofers to take the load off the mains, increase the sound quality and give you more and deeper bass response. The Vegas are made more for bands, the lowest notes they play are around 41Hz for the bass guitar. If you are listening to EDM and such, then having very large subwoofers are required to match up to the volume levels of the Vegas.

 

[conanski]

I currently own a pair of Cerwin Vega CVP 2153 aswell as a XTI 4002 power amplifier. I am using this setup in my living room.

Party On.

What i want to do in the first place, is to eliminate clipping. I have tried setting the limiter settings to -0.1dDBFS with default 0.1 attack and 1.0 release times, but the amplifier still indicates clipping.

OK here's the deal, 0dBFS is digital clipping while 0dBm is the point at which the amp will be at full power if driven with it's rated input voltage(1.4v), and there is something like 15dB difference between those two. In other words in order to set effective limiters to prevent any amp clipping they need to be at -15dBFS or lower.

I would also like to know if I should filter frequencies below/above 37hz/20khz since the speakers' are "unable" to play frequencies below/above those marks?

First thing you have to know is all of CV's published specs are pure fairy tale, thre is no way in hell these boxes will survive 4000 watts and probably won't at 2000w either, I'd suggest you stay with what you got. And in terms of filters yes definitely set a low cut filter, according to the user manual these things are 3db down at 48hz so it wouldn't be a bad idea to set a 12-24db low cut at 40hz if you drive them hard with heavy bass. You don't need a high cut filter however because all your digital components including the amp already have a 20khz brick wall filter to block A/D D/A conversion noise and your digital music is also bandwidth limited to about 20khz.

 

[DidrikHansen]

Party On.


OK here's the deal, 0dBFS is digital clipping while 0dBm is the point at which the amp will be at full power if driven with it's rated input voltage(1.4v), and there is something like 15dB difference between those two. In other words in order to set effective limiters to prevent any amp clipping they need to be at -15dBFS or lower.


First thing you have to know is all of CV's published specs are pure fairy tale, thre is no way in hell these boxes will survive 4000 watts and probably won't at 2000w either, I'd suggest you stay with what you got. And in terms of filters yes definitely set a low cut filter, according to the user manual these things are 3db down at 48hz so it wouldn't be a bad idea to set a 12-24db low cut at 40hz if you drive them hard with heavy bass. You don't need a high cut filter however because all your digital components including the amp already have a 20khz brick wall filter to block A/D D/A conversion noise and your digital music is also bandwidth limited to about 20khz.

Thanks for all the support, greatly appreciated!

I see you're mentioning low cut filters, well here's the deal. It seems that i am unable to create anything else then a low/high shelf filter in Band Manager. Do you have any recommendations considering the configuration of this type of filter?

This is how it looks like in Band Manager:

An externally hosted image should be here but it was not working when we last tested it.

 

[DidrikHansen]

I have an XTi 1002 and some thoughts

Set mine up about the same as yours but with -2.5dB for the limiter. The amp is used in my garage and the adjustable limiter prevents blown breakers (and visits from the police) Once the limiter is engaged, that red light is now indicating the limiter is kicking in. The amp is not clipping at that point. Mild flashes of the limiter is fine, if the light is constantly flashing--turn it down a touch to prevent cooking voice coils.

I would adjust the high pass filter to around 35Hz to prevent anything below that from hammering the woofers. That saves on power also, why waste power with the frequencies the woofers are not able to produce.

I think those Vegas are 4 ohms so you'll get 1,200 watts from the XTi 4002. The only thing an XTi 6002 will give you is blown speakers, blown breakers and that sort of thing. Assuming no power compression, 2000 watts would give you 2dB more output. You might notice it louder...but most likely it will sound about the same.

Your setup looks like it is for a house? If so, what you need is some subwoofers to take the load off the mains, increase the sound quality and give you more and deeper bass response. The Vegas are made more for bands, the lowest notes they play are around 41Hz for the bass guitar. If you are listening to EDM and such, then having very large subwoofers are required to match up to the volume levels of the Vegas.

Thanks for sharing your experience, greatly appreciated!

I've pretty much decided to keep my XTi 4002, as the system plays loud enough for me as it is.

I'm still trying to figure out how to correctly configure a high pass filter, because there doesn't seem to be such a thing available for configuration in Band Manager? I could only find low/high shelf filter.. and those work in a different way, right?

Sorry for asking stupid questions, I just want this done right..

Also, are there any specific subwoofers you would advice me take a look at? I've previously had a CV HFA 18SX, but it started going into protect mode, and eventually it caught fire..

 

[conanski]

Hi and low pass filters are in there so keep looking through all the menues and try directly on the amp as well.

Crown XTi Series2
Features:

- Highly readable backlit liquid crystal display that shows Signal, Ready, Power, Preset, Peak, and Processing status
- Power Supply Temperature and AC Line Voltage.
- Onboard HiQnet Band Manager and System Architect control software
- Input EQ with bypassable 6-band parametric filter
- Output EQ with bypassable 8-band parametric filter
- Highpass and Lowpass filters on each channel
- Subharmonic Synth with Frequency, Gain, and Filter Type settings
- 3 User-defined fan mode controls
- Visible AC line voltage and Power Supply Temperature monitoring
- 29 user-definable preset
- Locking power cord clip
- Integrated cast-aluminum handles
- Delay adjustment for driver signal alignment

 

[DidrikHansen]

Hi and low pass filters are in there so keep looking through all the menues and try directly on the amp as well.

Crown XTi Series2
Features:

- Highly readable backlit liquid crystal display that shows Signal, Ready, Power, Preset, Peak, and Processing status
- Power Supply Temperature and AC Line Voltage.
- Onboard HiQnet Band Manager and System Architect control software
- Input EQ with bypassable 6-band parametric filter
- Output EQ with bypassable 8-band parametric filter
- Highpass and Lowpass filters on each channel
- Subharmonic Synth with Frequency, Gain, and Filter Type settings
- 3 User-defined fan mode controls
- Visible AC line voltage and Power Supply Temperature monitoring
- 29 user-definable preset
- Locking power cord clip
- Integrated cast-aluminum handles
- Delay adjustment for driver signal alignment

I found the high/low filters, but I'm a little unsure about how to set this up.

An externally hosted image should be here but it was not working when we last tested it.

How many DB/octave should I use? And how should I configure the filters? At the moment it's -5db Butterworth 48dB/oct at 35hz both channels. All of the different dB/oct options are shown above.

Do you have any suggestions?

Thanks.

 

[18Hurts]

That looks like a good number

The 48dB per octave means it cuts the signal level 48dB down by around 17 Hz. Back in the day, they called those "brick wall filters" or very steep. I've never messed with my high pass filters with my XTi as far as bass management goes--I have it crossed at 80Hz and it runs the highs.

Subs to keep up with your Vegas and you've already burned up CV 18's--time to build some massive subs or buy some commercial concert subs so not to start them on fire.

I'm thinking along the lines of JTR Orbit Shifter LF. Horn loaded 18 inchers with 4000 watts of motivation built in. Two should hurt you, 4 will cause building damage so...
If you are really good with carpentry, don't mind moving 300 pound cabinets around and like to destroy walls etc--the Gjallerhorn is right up your alley.

If you don't require really, really deep bass--the Danley Sound Labs BC415 sub will do the trick.

https://www.youtube.com/watch?v=Mz6qQIfIx6s

 

[DidrikHansen]

That looks like a good number

The 48dB per octave means it cuts the signal level 48dB down by around 17 Hz. Back in the day, they called those "brick wall filters" or very steep. I've never messed with my high pass filters with my XTi as far as bass management goes--I have it crossed at 80Hz and it runs the highs.

Subs to keep up with your Vegas and you've already burned up CV 18's--time to build some massive subs or buy some commercial concert subs so not to start them on fire.

I'm thinking along the lines of JTR Orbit Shifter LF. Horn loaded 18 inchers with 4000 watts of motivation built in. Two should hurt you, 4 will cause building damage so...
If you are really good with carpentry, don't mind moving 300 pound cabinets around and like to destroy walls etc--the Gjallerhorn is right up your alley.

If you don't require really, really deep bass--the Danley Sound Labs BC415 sub will do the trick.

https://www.youtube.com/watch?v=Mz6qQIfIx6s

Those subs seem a bit too brutal

I'm not using this setup professionally, so I don't need that kind of performance.

I though the CV HFA 18 had more than enough power, I just want to avoid getting it again since it actually caught fire..

My budget is around 10 000,- NOK / 1300,- USD..

What do you think about this? Power Dynamics Aktiv Subwoofer 18 (Stk)

This website has a pretty good variaty of speakers/PA/Audio Equipment, but is sadly not translated in English.

// Soundshop.no // Active Speakers/Subwoofers - Høyttalere - Aktive

 

[conanski]

I found the high/low filters, but I'm a little unsure about how to set this up.

How many DB/octave should I use? And how should I configure the filters? At the moment it's -5db Butterworth 48dB/oct at 35hz both channels. All of the different dB/oct options are shown above..

Set the bandpass gain to 0db(no boost or cut) and set a HP Butterworth filter at 24dB or 48db/oct at about 40hz. Play some bass heavy music or pink noise through the system and adjust the HP filter up from 30hz until you hear it begin to impact bass output, then drop it back down a bit and set it.You will likely end up with a setting somewhere between 30 and 50hz.

 

[chris661]

24dB/octave is fine. It still cuts excursion very quickly, but doesn't have the extra group delay.

 

[18Hurts]

Those subs seem a bit too brutal

I'm not using this setup professionally, so I don't need that kind of performance.

I though the CV HFA 18 had more than enough power, I just want to avoid getting it again since it actually caught fire..

My budget is around 10 000,- NOK / 1300,- USD..

10,000 NOK should get you a pair of 18 inch subs from Italy, say RCF, B&C, 18 Sound or Faital PRO. Plenty of Baltic Birch plywood in your area so maybe a pair of 18 inch PA subs? If you run them passive, hook up a PA amp and set the filters and it is easier to see the displays on power output from and outboard amp.

One of those weird habits us DIY people tend to do in the winter time.