# What a $160 refurb Skar RP-600.5 Amp's guts look like...



## steelwindmachine (May 15, 2017)

I'm cheap, my ears are old and I sought to find an amp that would run my whole system out of one "box". This is what I picked up and thought I'd share what the guts of this amp looks like.

No, it's not the latest and greatest premium brand stuff, but I expect it'll be good enough to make relatively noise-free sound within my hearing range.

I might do some mods for fun such as by-passing the filter switches for channels 1-4 and see if I can bypass or resistor-out the always-on sub/channel-5 filter. Also, might change out the Yuscon caps to Nichicon or Panasonic for a probable improvement in durability. I'm not looking to mod this in the hopes of making perfect traces on a scope or analyzer. I'm fairly certain for the amount of work involved to change filter caps, op-amps, etc., that my ears likely wouldn't know the difference as I drive along with wind noise, traffic, etc.

Nonetheless, this is what you get for $160 shipped as of today to potentially run a whole 2-way front stage + sub. I'll be supplying signal to this via a MiniDSP 8x12DL (which I also bought used).






  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  







  




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*Some component info:*
Yuscon caps - all 105*C:
3300uf x1
2200uf 35v RK(P) x4
4700uf 35v RK(P) x2
22uf 250v NP x1
470uf 63v x1
100uf 50v RK(P) x2

Elcon LE 3300uf 63v x2 - can't find any specs on this on Elcon's site. Maybe discontinued?

Op-Amps:
TL074
TL072
both: 0.01% THD


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## chuyler1 (Apr 10, 2006)

I ran a PPI 5440 for years that made half that power and was about the same size. I love me a good 5 channel, it keeps things simple.


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## JohnnyOhh (Feb 19, 2015)

dude sick. now, what's the before and after performance of this bad boy, even if just form a spec perspective?

mods look niiiice.

what do you specifically get out of them? lower noise floor? higher signal to noise ratio? better emi filtering?


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## steelwindmachine (May 15, 2017)

@JohnnyOhh - I didn't do any mods. The photos are of the amp as-is from the factory/refurb - no changes by me.

I've mostly decided that other than maybe by-pass the filter switches for channels 1-4 and try to defeat/by-pass the sub channel subsonic/LPF and bass boost, I'm going to leave the rest of it alone. Yes, I could change out the Yuscon caps for more durable caps from Nichicon or the like and change the op-amps, but I don't believe it's worth my time at this point. I'd rather invest my limited time into getting the system installed and functional first.

I highly doubt changing out parts for anything other than durability will result in me being able to perceive any change in sound quality. I'm a middle-aged male and have tinnitus. As long as it doesn't hiss or cause turn-on popping, I expect this amp to be more than satisfactory for me.


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## JohnnyOhh (Feb 19, 2015)

yea totally. sorry, i misread, i thought you had modded it


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## CCole (Sep 9, 2020)

Thanks for the write up and photos. About 5 years ago I decided to get back into car audio again after running the same gear for 10+ years. I ran into skar and was baffled by the price per watt and seeing how they performed on a dyno. Ultimately I grabbed 2 RP2000 because they would allow me to recess them into the factory beauty panels under the rear captains chairs of my Tahoe. I figured if they were junk it would be a big loss. Granted I did drop $1500 upgrading my electrical but I couldn’t be happier. 
The 2K watt Zapcos are roughly the same size and Ive contemplated ordering them numerous times. However I can’t imagine the price difference would be worth the potential gains if any are to be had. 
Im eager to hear what you think once the 5-channel is installed and tuned. Sub’d


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## steelwindmachine (May 15, 2017)

@CCole - not installed yet, but am going to leave it as-is and maybe I'll do parts swapping after I've confirmed it's working well before I do anything.


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