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#16 Tornado99

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Posted 28 March 2022 - 06:21 PM

I would lean towards agreeing with sonscar to be honest, assuming the wiring is unchanged and hasn't suffered some sort of damage in the mean time which is causing a fault

still if the adding of earthing has cured the issue then thumbs up, enjoy your tunes and move on :)

glad you found a cure

interested to see the amp spec if you can stick a link on here at some point, just purely out of curiosity


Cerwin Vega 5 channel, D class, 2500 watt:

https://cerwinvega.c...cvp2500-5d.html

#17 stuart bowes

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Posted 28 March 2022 - 07:22 PM

well that's a new one on me but I don't pretend to be any sort of expert, the output ratings are certainly more substantial that what you had before 

 

I can't find a lot about them online but what comments I did find seem to be favourable

 

it is a bit odd about the interference though

 

what's it like when it's running now though, you like it?


Edited by stuart bowes, 28 March 2022 - 07:24 PM.


#18 Tornado99

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Posted 28 March 2022 - 11:26 PM

well that's a new one on me but I don't pretend to be any sort of expert, the output ratings are certainly more substantial that what you had before 

 

I can't find a lot about them online but what comments I did find seem to be favourable

 

it is a bit odd about the interference though

 

what's it like when it's running now though, you like it?

Just had car out for first drive since the mod on the RCA's...audio perfectly clear....still need to dial in my levels etc as they reset whenever the battery is disconnected from the HU (real old school...no EPROM within) but all working well. 

 

New 5 channel amp lets me run two fronts, four under rear seat (two pairs each in parallel) and two larger rear parcel shelf as subs, though don't think they are big enough to be considered actual subs. The amp has two sub pre-amp inputs, one sub speaker output, so I wire in the two parcel shelf in parallel. All speakers are 4 Ohm's each, Infinity brand. Seem to be a good quality set. 



#19 stuart bowes

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Posted 29 March 2022 - 08:21 AM

just bear in mind when you wire speakers in parallel it halves the ohms so 4ohm speakers become 2ohm (or 8ohm becomes 4, etc)  which is usually a good thing because you can use more wattage from the output

 

it can over work the amp though when used for periods of time depending on what the output is rated to

 

(in series you add the ohms together instead, it has the opposite effect)

 

not sure if you meant 4ohm as per the label on the speaker, or 8 ohm but now 4ohm due to wiring setup


Edited by stuart bowes, 29 March 2022 - 08:24 AM.


#20 Tornado99

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Posted 29 March 2022 - 08:57 AM

just bear in mind when you wire speakers in parallel it halves the ohms so 4ohm speakers become 2ohm (or 8ohm becomes 4, etc)  which is usually a good thing because you can use more wattage from the output

 

it can over work the amp though when used for periods of time depending on what the output is rated to

 

(in series you add the ohms together instead, it has the opposite effect)

 

not sure if you meant 4ohm as per the label on the speaker, or 8 ohm but now 4ohm due to wiring setup

 4 Ohm was printed on magnet of each speaker. 



#21 stuart bowes

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Posted 29 March 2022 - 09:07 AM

ok yeah so the ones wired in parallel are now running at 2ohm

 

so you're looking at this part of the spec 

  • 85Wx4 + 300Wx1 @2Ω RMS

depending on the wattage rating of the speakers that'll give you a rough idea of what percentage of the total volume control to use..

 

not sure how that is affected by the front pair running at 4ohm (probably fine to be honest) however you could correct it by adding a pair of 4ohm tweeters in parallel up front  (or just check every now and then to see if the amp is getting excessively hot)

 

is there not a 'memory' power supply to the head unit you can add permanent live to?  such as from the brown wire on the back of the headlight switch IIRC (if using as a daily driver im sure it would be fine)


Edited by stuart bowes, 29 March 2022 - 09:26 AM.


#22 Tornado99

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Posted 29 March 2022 - 08:49 PM

ok yeah so the ones wired in parallel are now running at 2ohm

so you're looking at this part of the spec

  • 85Wx4 + 300Wx1 @2Ω RMS
depending on the wattage rating of the speakers that'll give you a rough idea of what percentage of the total volume control to use..

not sure how that is affected by the front pair running at 4ohm (probably fine to be honest) however you could correct it by adding a pair of 4ohm tweeters in parallel up front (or just check every now and then to see if the amp is getting excessively hot)

is there not a 'memory' power supply to the head unit you can add permanent live to? such as from the brown wire on the back of the headlight switch IIRC (if using as a daily driver im sure it would be fine)
I was only losing hu settings b/c of need to disconnect battery posts or the hu multiconnector frequently during this troubleshooting. Settings are saved with ign off as there direct to battery feed into hu, just no backup for when no batt on line.

There were/still are little 9v battery with cig lighter male wiring to let you plug in to cig lighter socket to keep some power to radio memory when having work done with main batt off line. Modern hu's either have onboard lithium batt to keep the clock running like on a desktop computer or just an EPROM memory chip to keep all but clock setting alive.




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