Hi, I'm looking to find out which is the better amp of the two. I was looking for comparisons on which one has the best sound quality,Which was the more powerful amp, when both were run at 4 ohm loads.Did they both stay cool when running hard. Are they clean enough to run powerfull midrange,midbass,and tweeters if I wanted.,or is the sound quality only good enough for subwoofers.Thanks
The Zeus has a three stage power supply that switches to higher rail supply voltages so it runs cooler by design but its only a 900 watt mono amp. Similar to a class H amplifier design. So its Voltage drop issues are reduced by the three stage of the supply switching in and out as its pressed to full power. Most sub duty runs amps very close if not beyond their max output so even the special power supply design won't help much if the amp is at full output all the time on heavy constant bass line. Bass line in current recording is so compressed and such that modern musical content is way different then back when this amp was designed and built. Something to think about with all the class D amps available for cheap and all of them much larger power with less battery draw...
The A1200.2 is a unique amp since it is the only one of that time period to have a Full bridge power supply design but its also a 1200 watt mono amp that was originally designed to accept water or liquid cooling in its end plates so it could handle low ohm loads with better thermal control. Definitely oriented as a high SQ amp most were used for sub duty with some success, although any SQ properties were probably never seen or realized playing bass line content.
There was only one D class amp available back when theses amps ruled a 75 stereo 400 watt mono Infinity amp, as I recall and it had SQ issues if ran less then 4 ohms load due its output filter design used back them. So these beasts were the class AB big boys up against Rockford 700 and 1000's and a host of other large amp in the kilo-watt range of output for a number of makers back then. Everybody had one of some kind, because there was a market for them. Not so much today with D class amps in the 10 kilo-watt range being available.
Both had unique power supply design ideas in them but vastly different approaches and varying results in use. Both used Class AB like audio designs although I have heard the Zeus has crossover notch distortion according to ZED himself, and the PPI did not have any such distortion related issues because of its more elaborate amp design.
If your looking for a sub amp use a modern class D amp and be done with it. Little to no heat issues to speak of, much larger power factors available, at half the current draw off your charging system and I agree with everyone else you not likely to hear and SQ related issues. Plus cheap to replace when it fails, and they will fail. Just look at the repair threads here on this forum. most are sub amps.
1200 watts of highs is a bit much. Most I ever ran was 200 X 4 channels. It was very reliable and less speaker were hurt using that much clean power. Clipping usually cooks off tweeters voice coils, so lots of clean highs power means less clipped info to burn up voice coils.
Anyone here will be hard pressed to give you an answer that will fit all needs your looking at, since while these amps have some similar power ranges they are all different in design and approach to the end and means. And your end use is wide open in your question.
The A1200.2 is a unique amp since it is the only one of that time period to have a Full bridge power supply design but its also a 1200 watt mono amp that was originally designed to accept water or liquid cooling in its end plates so it could handle low ohm loads with better thermal control. Definitely oriented as a high SQ amp most were used for sub duty with some success, although any SQ properties were probably never seen or realized playing bass line content.
There was only one D class amp available back when theses amps ruled a 75 stereo 400 watt mono Infinity amp, as I recall and it had SQ issues if ran less then 4 ohms load due its output filter design used back them. So these beasts were the class AB big boys up against Rockford 700 and 1000's and a host of other large amp in the kilo-watt range of output for a number of makers back then. Everybody had one of some kind, because there was a market for them. Not so much today with D class amps in the 10 kilo-watt range being available.
Both had unique power supply design ideas in them but vastly different approaches and varying results in use. Both used Class AB like audio designs although I have heard the Zeus has crossover notch distortion according to ZED himself, and the PPI did not have any such distortion related issues because of its more elaborate amp design.
If your looking for a sub amp use a modern class D amp and be done with it. Little to no heat issues to speak of, much larger power factors available, at half the current draw off your charging system and I agree with everyone else you not likely to hear and SQ related issues. Plus cheap to replace when it fails, and they will fail. Just look at the repair threads here on this forum. most are sub amps.
1200 watts of highs is a bit much. Most I ever ran was 200 X 4 channels. It was very reliable and less speaker were hurt using that much clean power. Clipping usually cooks off tweeters voice coils, so lots of clean highs power means less clipped info to burn up voice coils.
Anyone here will be hard pressed to give you an answer that will fit all needs your looking at, since while these amps have some similar power ranges they are all different in design and approach to the end and means. And your end use is wide open in your question.
Thank you onemoreamp. You definitely know your stuff. If you had to pick one of the two amps for which one had the better sound quality,which would you pick. Also is the PPI amp, the overall better built internally amp, and did people find that adding the water to the PPI amp ,make the amp run a lot cooler ,or do these amps already run cool ,and the water,just made it a lot better or was it a gimmick. Thanks
The PPI uses the ceramic driver boards that are no longer available and are sometimes unrepairable (or impractical to repair).
Should I stay clear of the PPI amp then because of that.,or were they built so well, that it was never a problem.Or were these prone to failure quite a bit. That would be pretty risky to buy one if they failed quite a bit,and you couldn,t get parts to fix it. I was just looking for an oldschool A/B class amp with very low distortion with full sound that put out 300 rms watts at 4 ohm. Is there anything else oldschool that you guys know of that delivers in what I am asking about. Both of you seem to be a wealth of knowledge.
That would depend on you. For some people, the cost of the amp is absolutely insignificant and if it fails, they'd send it to a landfill without a second thought. For others, this may take a lot of sacrifice to scrape up the money for the amp. You also have those who want something that they buy to be easily repairable with readily available parts. I don't know where you fit in that mix.
The driver boards fail and tend to fail more often in the higher powered amps.
Except for the crossover/equalization sections of amplifiers, the power amplifier stages will all sound virtually identical because they use global feedback that constantly corrects for distortion.
In my opinion, the amp that's going to sound the best is the one that has significantly more headroom (rail voltage) than others. That allows it to play louder without being driven into clipping. Depending on what you listen to, that can be a significant factor. For example, if you listen to music sources with no compression (Sheffield Lab products for example), the softer passages are recorded at a level so that the louder passages aren't driven to clipping on the media (CD...). For a piece of music with significant dynamic range, that would require that an amp have enough power (rail voltage) to allow the softer passages to be adequately loud and not clip on the peaks.
The driver boards fail and tend to fail more often in the higher powered amps.
Except for the crossover/equalization sections of amplifiers, the power amplifier stages will all sound virtually identical because they use global feedback that constantly corrects for distortion.
In my opinion, the amp that's going to sound the best is the one that has significantly more headroom (rail voltage) than others. That allows it to play louder without being driven into clipping. Depending on what you listen to, that can be a significant factor. For example, if you listen to music sources with no compression (Sheffield Lab products for example), the softer passages are recorded at a level so that the louder passages aren't driven to clipping on the media (CD...). For a piece of music with significant dynamic range, that would require that an amp have enough power (rail voltage) to allow the softer passages to be adequately loud and not clip on the peaks.
Eh, I was around back then and have worked on many of them over the years, but thank you for your kind words. I was a big PPI fan/user until Phoenix Gold came around in the 91 92 time frame. I became a PG fan because of superior electronic engineering involved inside of the amp, not SQ reasons. I saw and understood what PG did and felt it was well thought out from a safety and reliability, and repair-ability point of view.
SQ is a personal taste related issue, in most cases. And there has been a fair amount of discovery concerning amp SQ that shows that many people can not distinguish one amp from another in blind fold tests. Its all open to conjecture, and personal tastes and what you think you can hear and perceive. Tube lovers only like tubes, Transistors folks like what they like. I have heard some horrible sounding amps over the years, but they were mostly poorly designed in the first place.
Liquid cooling of any amp for the most part appeared to be a fad back then. In the case of the Art series amps I feel that PPI hoped it would catch on and be used a lot more then it did. but back then installers had no idea how to rig the hydraulics of a liquid heat transfer system, so without some factory support and or training in heat exchange technology I think it was mostly a waste in the wrong hands in many cases. Plus just because you kept the sink cool this did not mean you could supply additional cooling to the drive electronics since only the main power devices ever saw any thermal relief, so the main board devices tended to cook off with little or no help what so ever. PPI went to fans in the next PC and PCX series, like most other amp companies.
The last A1200.2 I had to test I could only test one channel at a time due to power supply limitations and it failed to meet its 2 ohm rating even with a 90 ampere supply feeding it. It also ran very hot very quick into test loads and due to its internal design < I.E. voltage drop issue related to the 65 volt rails> and its pretty smooth surface heatsink its heat emissions we not a good as some other amps with higher surface area exposed to emit the heat away. Plus you got to take into account the hot car trunk your loading all this gear into the math picture, so its not always so clear what works best on the bench as opposed to inside of a car. The heat build up in most cars will trigger the amps protection anyway just because the amp can't breath fresh cool air to dump the ~ 50% heat load of the full power draw the amp pulls on your charging system.
These amps typically are 50% efficient, so only half the 12 volt power gets to the speakers and the other 50% ends up being heat loss that stores in the sink if the amp has no fresh cool air source to dump all that heat build up.
In a nut shell buy a class D amp for bass. Your thermal losses will be minimal, and more bang for the buck. Also there are many full range D class amps on the market, so your highs can now be clean and cool while operating. The 12 volt power environment is a big problem, and always has been. limited power from the source the autos charging system, and limited heat exchange no matter what sink design just because of how cars get this gear installed with no fresh cooling air source to dump heat load into the air movement.
All of this was known about the whole time along the way from the beginning. hence why class D and PWM D class amps came into being after the technology had been developed and shrank to single IC chip sized solutions. And even now in the current day, It takes DC power to make Audio power, so unless you can supply huge amounts of DC power in the first place even the biggest amp of any design will wimp out and cut off and not operate anywhere near your desires.
Your asking a lot of questions, and I hope I have helped some with a few of the answers. Reality is I hope I have you asking even more questions now though since the power factor side of the equation is now open on the table for you to think about. Most autos can't run either of these amps anywhere near their true potential just because the stock cars power system just wasn't ever meant to handle these big beasts...
"You have to have DC power to make audio power"😉
Hi, you guys definitely keep me on my toes with all your great knowledge. I have had my amps in my car now for on and off a little over 20 years now. So I'm definitely not interested in buying an amp that goes into the landfill quickly. I'm interested in amps that are oldschool,with quality internals,with good sound quality. I definitely need a quality amp like perry says that has a lot of power giving me a lot of headroom,so I don't half to use all the power,risking clipping and distortion. That is my problem right now. Even though my stereo is very clear,I can turn it right up to maximum volume and I would like it so like perry described I have lots of headroom ,and only half to turn it up to half volume to get it as loud as it is right now at full volume. Right now I am using two alpine 3544 amps.One for the front 3 way ,and one for the back 2 way and an alpine 1505 for the 2 subwoofers. My crossovers have the ability to be bi-amped so I could probably add a couple more 3544 amp in there ,and take care of the headroom for my midrange ,midbass,and tweeters, But will still need a lot bigger amp for the subwoofers.I half to brige the alpine 1505 just to get it to move the puny 10 inch subs I have,and after a few songs,depending how much bass is in the song,Just regular music like supertramp, Elton John,Phil collins,etc ,and in about an hour,I'm fearing for the amp,it's so hot.Is there a quality ,last for years like oldschool amps,or an oldschool amp, I can use for my subwoofers that will give me detailed bass,and the headroom so I have the extra power on tap,when things get loud,which it does quite often. Each sub is a sound quality sub,not spl sub, and says on each subwoofer,that it needs 400rms watts just to function, Who makes an amp that can deliver the clean watts,with the headroom for them. I know headroom,while staying super clean at high levels is my biggest ,and pretty much my only issue right now.Every thing sound quality wise sounds good.Just run out of power. I know with you guys help I will get to where I need to be,and be able to really enjoy listening to my stereo. Thanks
Unless you have a large number of 10's series/paralleled together, the 1505 should be moving them quite a bit. If it is not, you may want to check each individual sub.
SQ is not an issue with subwoofers. Any amp in good working order will produce power clean enough that no distortion will be heard until the amp is driven into clipping.
If your speakers are the competition types that have suspension so stiff that you almost have to stand on the cones to get them to move, you have a mismatch for the amp you have.
There haven't been many specifics here (vehicle, equipment, desired SPL output level...) so it's hard to make any recommendations but for most people (who aren't bassheads), the 1505 and the right pair of 10's in a properly designed enclosure would be sufficient.
SQ is not an issue with subwoofers. Any amp in good working order will produce power clean enough that no distortion will be heard until the amp is driven into clipping.
If your speakers are the competition types that have suspension so stiff that you almost have to stand on the cones to get them to move, you have a mismatch for the amp you have.
There haven't been many specifics here (vehicle, equipment, desired SPL output level...) so it's hard to make any recommendations but for most people (who aren't bassheads), the 1505 and the right pair of 10's in a properly designed enclosure would be sufficient.
Hi,My car is a 1993 ford thunderbird. The stereo is an alpine anniversary 7909, alpine 3321 eq,There is one focal utopia 4 inch,alpine f1 6/1/2 midbass,and alpine 6010 tweeter in each door. In the rear deck there is another oldschool alpine 5 1/4 and dynaudio tweeters. In the trunk there is 2 alpine 3544 amps .One for the front speakers ,and one for the back. It is all separated up with 2 flagship alpie spx-f17t 3 way crossovers. and there is the alpine 1505 amp running 2 sws-1242D subs. These were just supposed to be temporary ,and be swapped out for 2 12 inch oldschool alpine 6012EX subwoofers,but when the 2 10 inch subs started heating up the sub amp to burning hot levels within an hour or so when driving hard. I decided to hit these forums to see if I could find another oldschool amp that was a lot bigger with lots of 4 ohm power so I would have a lot of headroom, so I would be able to run the amp at low power ,so it wouldn't half to work to the max,and not half to bridge it so the amp wouldn't be working ball to the wall all the time. That when I started looking at the Hifonics Zeus amp since it was 600 rms watts at 4ohm,and the PPI amp. Since the rest of my stereo is oldschool.,and I would like to keep it oldschool. Is the hifonics amp my best reliable choice,or is there an even better oldschool amp I should be looking at to give me over 300 rms watts at 4 ohm to deliver lots of headroom I desire.I would take an amp with lots more power,and just dial it down. With you guys much more knowledgeable than me.Hopefully you can steer me to a high quality built oldschool amp that will get the job done the first time. Thanks
I am familiar with the alpine 1505. I have one here for repair right now from running two subs. And if your running that amp hot you need way more power then your aware of, and or your 12 volt system in your ride is already out of power just running that amp. And its a nice clean class AB amp. Old Alpine was fairly good stuff, and this amp was built like a beast inside.
buy a class d amp, any class d amp. No heat, and twice the volume bang for the buck on what you got for your 12 volt power already without rebuilding your rides electrical system.....
I seriously doubt anyone here that works on amps will disagree with these facts....😉
ALL old school amps run hot at full output, they only output 50% of their input power as audio power, the rest is HEAT. Their isn't ANY class AB map that will run cool in the trunk of a car. If the audio output does not make them hot the heat inside your trunk will...Is your trunk air conditioned??? well all the heat build up is trapped back there, unless your riding down the street with your trunk open to the elements and some fresh cool air.....its gonna run hot.
buy a class d amp, any class d amp. No heat, and twice the volume bang for the buck on what you got for your 12 volt power already without rebuilding your rides electrical system.....
I seriously doubt anyone here that works on amps will disagree with these facts....😉
ALL old school amps run hot at full output, they only output 50% of their input power as audio power, the rest is HEAT. Their isn't ANY class AB map that will run cool in the trunk of a car. If the audio output does not make them hot the heat inside your trunk will...Is your trunk air conditioned??? well all the heat build up is trapped back there, unless your riding down the street with your trunk open to the elements and some fresh cool air.....its gonna run hot.
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I have used both the PPI and Zeus.I liked the Zeus better.
However,there are a few more you should consider.
Kicker ZR1000 or ZR600.The 1000 does more like 1200watts and the 600 I just benched a few days ago at 800RMS into 4 ohms.
The Orion Xtreme 1200 or 1400 are my favorite old school amps for subs.
If you are running the amps at 4 ohm stereo all these amps do more at 4 ohm then rated.The Zues,PPI,ZR1200 and Xtreme 1200 put out about 350x2 at 4ohm and are fully regulated.However,when bridged at 4 ohm they all tend to sag a bit due to the voltage at the terminals dropping to 11volts or so.
The Zeus has a trimmer potentiometer so the rail voltage can be raised to produce over 400x2 at 4 ohms but only if the terminal voltage stays above 12volts.
If you are good at level matching,running 2 smaller amps,one on each sub will give you a lot more options.2 PPI A600's or 300's.MTX Thunder2160's or Alpine MRV-T757 are a few options.
As mentioned numerous times.All these amps will run hot to the point of thermal shut down if driven hard for any length of time.A fan can help the run time a lot but in a 150+degree trunk it it can only do so much.And keep in mind the hotter any electronic item runs,the shorter its lifespan.
However,there are a few more you should consider.
Kicker ZR1000 or ZR600.The 1000 does more like 1200watts and the 600 I just benched a few days ago at 800RMS into 4 ohms.
The Orion Xtreme 1200 or 1400 are my favorite old school amps for subs.
If you are running the amps at 4 ohm stereo all these amps do more at 4 ohm then rated.The Zues,PPI,ZR1200 and Xtreme 1200 put out about 350x2 at 4ohm and are fully regulated.However,when bridged at 4 ohm they all tend to sag a bit due to the voltage at the terminals dropping to 11volts or so.
The Zeus has a trimmer potentiometer so the rail voltage can be raised to produce over 400x2 at 4 ohms but only if the terminal voltage stays above 12volts.
If you are good at level matching,running 2 smaller amps,one on each sub will give you a lot more options.2 PPI A600's or 300's.MTX Thunder2160's or Alpine MRV-T757 are a few options.
As mentioned numerous times.All these amps will run hot to the point of thermal shut down if driven hard for any length of time.A fan can help the run time a lot but in a 150+degree trunk it it can only do so much.And keep in mind the hotter any electronic item runs,the shorter its lifespan.
Hi, My electrical system has already been updated with heavy power and ground wires,and 2 caps,Though my brother says I don't need the caps if my ground is heavy and good. Not sure about that myself. I also have a big semi aftermarket 240 amp alternator . The caps are reading 14.4 volts. I'd rather spend more money on a good amp ,unless you know of a class D amp that some company sells that sounds like a class A/B ,but is a class D. Also what about an amp that starts out as class A/B at lower to medium watts,and when it gets into the higher demanding volume levels,it switches to a class D to stay cool. I definitely understand ,it is also almost impossible to keep amp cool in a small trunk.Especially in the summer time. For the next poster talking about the other old school sub amps.Do you know the Orion amps to sound better ,and give more controlled start and stop bass ,Than the Kicker amps.also you said the Orion 1200 puts out about 350 rms watts per channel at 4 ohm stereo,What does the Orion 1400 amp put out. I have never used any of these amps. I would like to stay away from the PPI amps since they have ceramic boards inside,and if they need to be repared.They cannot be because they don't make them anymore. I'm looking for something like my oldschool alpine amps have been to me, and have stood the test of time for 20 + years.,and sound great Which of these amps are like that. also I'm not saying I won't run a class D amp,or an amp that turns into class D. I'd just like to keep the system oldschool. Plus no one has mentioned quality class D amps that sound good.With lots of headroom.
No one makes an amp that switches mode of operation from class AB to D. Two completely different concepts and designs internally, so nothing is compatible except the input op-amps gain control stages and crossover filters, from there on out its a totally different concept. Class AB is analogue technology linear technology, Class D is digital. Two completely different concepts..
And there are plenty of OK sounding full bandwidth class D amps nowadays. Your phone uses one. Almost everything uses this technology now even your LED TV. So you might want to look into it a bit more. This forum even has an entire class D section on its own. You might give it a look see...😉
And there are plenty of OK sounding full bandwidth class D amps nowadays. Your phone uses one. Almost everything uses this technology now even your LED TV. So you might want to look into it a bit more. This forum even has an entire class D section on its own. You might give it a look see...😉
I will give the class D amps a look over. Are there class D amps that you know of, with your years of experience, That sound as good as the class A/B amps,or are darn close to them in sound quality. There must be a company ,that is doing it better than others. Thanks
If this is for subs, SQ isn't an issue. Subwoofer cones are so heavily damped that there's no way to hear any distortion other than clipping from an amp in good working order.
Hi, Yes the amp is for subwoofers, But I'd also like the ability to use the amplifier for midrange,midbass ,and tweeters for piles of headroom as well.That's why I was preferring an oldschool A/B class amp ,so I could use it for anything. After talking with you I also get subwoofer distortion will not be much of a problem,as long as there is piles of headroom.
It's unlikely that you'll find one amp that will do what you want. Most of the full range class D amps are relatively low power. I've never seen anything in the 1000w+ category in full range class D. Maybe someone else can offer suggestions for such an amp.
How hard is it to install a fan or fans into my alpine 1505 amp.There are no fan or fans installed in that amp.You would think that would help to keep it cooler. I have seen fans on the alpine 3545 installed on the side. I have also seen them on top in Orion amps . Is this easy to do,and where do you guys think the best place in the amp would be to put them for maximum cooling.I would imagine that you would need holes cut somewhere for the heat to leave as well.
Its been a while since I messed with the Orion Xtreme amps But I still have a few of them laying around that I modified into medium current amps to run 6 pairs of mids in stereo mode,
But if I remember correctly the 1400 uses 75 or 80 volt caps vs the 63 for the 1200 but both were the same uf.I think they put a few more windings on the transformer secondary and a higher voltage Zener diode in the 1400 that regulates the rail voltage.Other then that they are the same amps.The circuit boards for these amps are used on the HCCA's.Actually,the board has HCCA 275/1200XTR printed on it.I believe the 1400 did about 50 more watts Per channel in stereo but did not have any increase in power over the 1200 when bridged.I believe the transformers were the same for all these size amps.
I really appreciate your enthusiasm and the fact that you ask questions.However,you are thinking too much about it.I know you want to choose the best old school amp for your application but unless you can work on them I would avoid them for sub duty and listen to everyone when they say class d is the way to go.Pushing these old amps with leaky caps and dried up heat sink compound wont last very long.Plus there not very cost friendly.
For the same price as a Zeus,PPI or Orion you can get a Rockford 1500bd.
I think a used RF T1000BD would be perfect for your subs and they go for $200-$250.
I use to use these old school amps and switched to Class d long ago.At one time I had 8 15" subs running on 4 Zeus's then XTR1200's.I swapped them out for 4 MTX 81000d's and never looked back.
Currently I am running 2 MTX 8500 12's on a JBL GTO1201 and it is so solid hitting it his hard to see when driving.It vibrates my skull bad enough I cant read plates on cars in front of me.
On a side note.It takes twice the power to get a 3db increase in output so going from 300 watts per channel to 400 per channel will hardly be noticeable,if at all.
But if I remember correctly the 1400 uses 75 or 80 volt caps vs the 63 for the 1200 but both were the same uf.I think they put a few more windings on the transformer secondary and a higher voltage Zener diode in the 1400 that regulates the rail voltage.Other then that they are the same amps.The circuit boards for these amps are used on the HCCA's.Actually,the board has HCCA 275/1200XTR printed on it.I believe the 1400 did about 50 more watts Per channel in stereo but did not have any increase in power over the 1200 when bridged.I believe the transformers were the same for all these size amps.
I really appreciate your enthusiasm and the fact that you ask questions.However,you are thinking too much about it.I know you want to choose the best old school amp for your application but unless you can work on them I would avoid them for sub duty and listen to everyone when they say class d is the way to go.Pushing these old amps with leaky caps and dried up heat sink compound wont last very long.Plus there not very cost friendly.
For the same price as a Zeus,PPI or Orion you can get a Rockford 1500bd.
I think a used RF T1000BD would be perfect for your subs and they go for $200-$250.
I use to use these old school amps and switched to Class d long ago.At one time I had 8 15" subs running on 4 Zeus's then XTR1200's.I swapped them out for 4 MTX 81000d's and never looked back.
Currently I am running 2 MTX 8500 12's on a JBL GTO1201 and it is so solid hitting it his hard to see when driving.It vibrates my skull bad enough I cant read plates on cars in front of me.
On a side note.It takes twice the power to get a 3db increase in output so going from 300 watts per channel to 400 per channel will hardly be noticeable,if at all.
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