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JPM.

Member Since 27 Apr 2010
Offline Last Active Oct 13 2013 03:16 AM
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Posts I've Made

In Topic: Cooked Voice Coil with Itech HD

10 October 2013 - 04:52 PM

View Postdakos, on 10 October 2013 - 08:19 AM, said:

Just one thing, the manual says to use minimal impedance when available and not nominal, that's how I got 51V (=SQRT(0.8X500X6.5)).

As for the response time, since it's a parameter of the driver, I would try to get it from peaveys support or even talk directly to Marty on the peavey forum. My logic tells me shorter response time as well.
Avi

Except for the Thermal Limiter. It says to use nominal. The wizard uses what ever you enter on all of them. But yeah, when you look at JBL specs on some drivers the Thermal Limiter is lower in comparision. 51 Volts looks like a go.
Marty retired a while a go and I've been down this path before with Peavey. When you use different brands in a system no one can be sure what is right as they can't validate each others settings for their equipment. They don't always translate well over other platforms. I don't think I will mix brands next purchase. It is a lot easier to get support that way.

I think it could be a case of operator error and nothing is bullet proof even with 3 limiters. I will try the Thermal at 51 volts at least as the rest of the settings seem right.

Thanks for your input Avi.

In Topic: Cooked Voice Coil with Itech HD

10 October 2013 - 05:20 AM

Bi amped sorry. The 12 inch woofer has its own amplifier channel and processing. I have looked at the nice brown voice coil. The new ones also have some brown in them but this one is way more brown and open circuit.
The thermal rating is set as the guide says to. Lets say the 2 hour rating is 500 watt. Square root of (0.8 of 2 Hour Rating x Nominal Impedence).
It is the first thing I'm thinking of changing with maybe less response time.

In Topic: Cooked Voice Coil with Itech HD

10 October 2013 - 04:38 AM

Hey Avi,

Its all cool. After reading through my posts I'm not quite explaining it right. Such as the 100hz to 2k bandpass could still mean a passive network etc. My config is clear in my head but I deal with it all the time. I'm still irritated that I send out systems with operators that have wireless monitoring of limiter action on all amps yet damage still occurs.
Another thing is I don't like bringing brands and models into it on a public forum. It disputes advertised ratings which can be circumstance dependent. I have for example seen the Crown Itech HD specs put under scrutiny on a public forum by someone who works for another brand. I don't think that is right. Lets just deal with ratings.  I have stated everything that is available.

Any way, you should have a read of this. It shows how I come to some of my settings. I do not use auto mode except to set the release times. There is a limiter wizard there to but it doesn't fully follow the guide for some reason. It only deals with nominal impedence, not minimum.

www.crownaudio.com/media/storagebk/pdf/support/ITech%20HD%20LevelMax%20Limiter%20Readme%20File.pdf

As for power compression, sure it has an effect but we are not talking about subs here. Its a mid driver and it really only drags down performance. It is more of a side effect of voice coils heating up but not really the cause of them burning out. But maybe accounting for it might provide the protection needed. Still, with a 3 step limiter system, do you need to allow for it? Itech HD guru may be able to answer that.

In Topic: Cooked Voice Coil with Itech HD

09 October 2013 - 05:01 PM

No, I actually do mean thermal limiter.
With respect, it's apparent you do help to a lot of people on this forum but I don't think you are able to help in this case.  I'm not chasing a lesson in speakers 101 but someone with extensive Itech HD knowledge.
I can tell you are not familiar with this particular amp.
Thanks


In Topic: Cooked Voice Coil with Itech HD

09 October 2013 - 05:11 AM

Sorry, I assumed you picked up that it is biamped since it was a 12 inch woofer with a bandpass of 100hz to 2K.

The driver is a Peavey TC 12, rated to 500 Watt Continuous, 2000 Watt Peak, Minimum Impedence is 6.5 Ohms, Nominal Impedence is 8 Ohms.
I have been entering 57 Volts for RMS Limiter, 0.193 Release and 114 Volts for Peak Limiter, 0.060 Release and 56.5 Volts for Thermal Limiter, 10 Sec response.