best mono sub amp? 1000Wrms and main amp
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=48949
Printed Date: July 13, 2025 at 8:55 PM
Topic: best mono sub amp? 1000Wrms and main amp
Posted By: VWBobby
Subject: best mono sub amp? 1000Wrms and main amp
Date Posted: January 30, 2005 at 4:48 PM
Hi guys,
I have 2 Phoenix Gold Titanium 12" subs. They are rated for 500 watts RMS Each..
I only have a 75 amp alternator available for my van ('65 vw bus).
What amp is the most efficient Class D mono amp available with around 1000 watts RMS? I don't want to harm my alternator. What should I use for batteries? I have a Red top Optima already.
I have a Kenwood KAC-7201 and a Rockford 501x
amp. How do these amps compare for main speaker use? I was going to run 2 sets of speakers off the kenwood even though its a 2 channel amp.
Thanks!!
-Bobby
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(2) PG Titanium 12's
(2) SoundStream Tarantula6.5's
(2) Alpine 6x9's
Kenwood KAC-7201 amp
Rockford Punch 501x amp
Replies:
Posted By: Alpine Guy
Date Posted: January 30, 2005 at 5:38 PM
The alpine MRD-M1000 (year 2003) MRD-M1001 (year 2004) from alpine are very efficient amps, there the same, just a few changes in cosmetics. But im very certain you will have problems keeping your battery's charged. You may have to look into a custom alternator install.
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2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.
Posted By: deocder
Date Posted: January 30, 2005 at 7:26 PM
I am partial to the Orion amplifiers.
Orion Amplifiers
Posted By: bullman96
Date Posted: January 30, 2005 at 7:56 PM
that kenwood amp is clean up to 100watts rms. it gets rather toasty at 100watts per chan at 4 ohms. 2ohms and you will probably fry it. i would also get another amp for your mids and highs, that amp is far from efficient. it strains my electical system more than my sub amp does. funny as hell to see your lights flicker, not from the lows, but from the mids.
Posted By: yamahaking2000
Date Posted: January 30, 2005 at 8:06 PM
use capacitors.... enough said...
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2 Infinity Kappa Perfect 10.1D - Sony crap amp(cant find my specs lol)
Posted By: bullman96
Date Posted: January 30, 2005 at 8:20 PM
i hope he is kidding. this has been gone over in this forum enough. you are going to have to get a custom built alternator, make some modifications to your engine to hold another alt., or keep the volume low. caps wont help
Posted By: pimpincavy
Date Posted: January 30, 2005 at 8:32 PM
Dont listen to yamahaking, capacitors are a waste of money and will only hurt your cars electrical system if it is not up to par to begin with.
I would suggest looking into the HiFonics Brutus 1000D, its a great amp for a amazing price, it can be had for under $200 on ebay and some websites, just shop around.
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Posted By: VWBobby
Date Posted: January 30, 2005 at 9:11 PM
I have been looking at the HiFonics amp threads... looks like great amps for the money!! I don't really like the way it looks, but sound is more important than appearance. bullman96 wrote:
that kenwood amp is clean up to 100watts rms. it gets rather toasty at 100watts per chan at 4 ohms. 2ohms and you will probably fry it. i would also get another amp for your mids and highs, that amp is far from efficient. it strains my electical system more than my sub amp does. funny as hell to see your lights flicker, not from the lows, but from the mids.
The Kenwood KAC-7201 is only good to 100watts rms??? The specs say its good for 230 x 2 @ 4 ohms RMS...but I'll trust your word since you've actually used this amp. It also says 2 ohm stable. All my stuff is still NEW in the boxes. The 2nd part of your reply; are you refering to the Rockford 501x? If its not a good amp, I'll probably end up selling it or putting it on ebay.... What's a good efficient amp for mids and highs? I know that its been covered in the forum, but most people don't look at efficiency as much as peak power... I'm more into efficiency at good RMS levels. Talking with a friend of mine, it looks like I might be able to fit a GM 1 wire alternator to my engine with some work....but REALLY want to avoid that at all costs (for many reasons). ------------- (2) PG Titanium 12's
(2) SoundStream Tarantula6.5's
(2) Alpine 6x9's
Kenwood KAC-7201 amp
Rockford Punch 501x amp
Posted By: stevdart
Date Posted: January 30, 2005 at 9:49 PM
Figure 90% for efficiency of a class D amp. To get 1000 watts of power using a 13.5 volt source, and with an efficient amp, the draw on your alt will be upwards of 81 amps. (Ohm's Law I = P/E) You need to do the alt upgrade, and upgrade the engine bay wiring too. '65 VW buses were built for AM radio, remember? lol
Posted By: VWBobby
Date Posted: January 30, 2005 at 11:10 PM
stevdart wrote:
Figure 90% for efficiency of a class D amp. To get 1000 watts of power using a 13.5 volt source, and with an efficient amp, the draw on your alt will be upwards of 81 amps. (Ohm's Law I = P/E) You need to do the alt upgrade, and upgrade the engine bay wiring too. '65 VW buses were built for AM radio, remember? lol
Thanks! Yeah, mostly they were meant for AM, but they did have FM radios as an option.  The stock generator was 38 amps (max) so a 75amp alternator is quite a "lot" for a VW....but I might have to come up with something more custom. I'll have to find a good car stereo store and let my ears do the shopping, then come back to the net to get a good deal.... ------------- (2) PG Titanium 12's
(2) SoundStream Tarantula6.5's
(2) Alpine 6x9's
Kenwood KAC-7201 amp
Rockford Punch 501x amp
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