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Posted By: Thasp Yet another amp question - parasound and hum. - 07/16/04 11:59 PM
This is so I have another option on my crusade for cheap, used, quality amps. I want to have many options incase the stuff I'm looking at right now gets sold.

Do the current Parasound two channel amps have hum? Not the expensive, flashy Halo stuff, but the normal amp and normal preamp?

These amps seem like a great option but I read about the humming in some Parasounds and it irked me a bit. The last thing I want to do after trying a cheater plug and sorting out the probs is hear a hum from the speakers. If anybody has any links, experience, etc about these models I'd be glad to hear it. Also, how should I go about using the cheater plug? Should I plug everything into a powerstrip with all three prongs then plug the power strip into the wall with the cheater plug, or should I plug things into the power strip with the cheater plug? What brand power strips and plugs are the norm, or will any do(ok, I'm perhaps a bit paranoid on that one )

Thanks again.
The links don't seem to be working.I have owned one Parasound product,it was the PHP850 pre-amp.I had it hooked up to a Kenwood basic M2A amp.I heard no ground hum from it at all.As far as bang for the buck it would be hard to beat.
Power is power. Don't worry about particular brands. I recall one link from the horses mouth where a seller of premium outlets said that he just took regular outlets, coated them in silver, and sold them for a fortune. In other words, no science behind it, and he could hear no difference.

If you're messing with cheater plugs to get rid of ground hum, I'd have your electrical system looked at by a professional electrician. I don't know much about it, but I'd say that a properly grounded and wired electrical system should not have to have cheater plugs in it in order to prevent hum.
I think this is true to a certain degree but when pushed hard power is not all the same.If this were true than any ol reciever could handle the M80's.When you have a harder speaker load there is a differance in power.Not all recievers will push the 80's but most seperate amps should do fine.
Are we talking about amp power here or electical?Man I think I'm confused.
I think that's a fallacy. You're talking about power supplies->amplifiers, I'm talking about power->power supplies. The power supplies should be able to handle stuff that's around the right voltage and amperage just fine. If the power supply does not supply adequate power or the amplifiers don't amplify it enough or adequately, then the given amp can't handle 4 ohm speakers.
I'm not quite sure what you mean.If an amp can't handle a certain load what differance would it make where its shortcomings are.
I mean the internal component that actually does the amplifying. I think we're talking at cross purposes here...

My contention was that any given power strip or cheater plug won't make a difference.
As the early post said I was confused.Sorry about that.In that case you certainly correct.
Not a biggie... I was a bit confused on how we got onto the amp thing myself.
Thanks,
I thought he was looking to find out about Parasound products.When I re-read the post I see he was also talking about outlets and cheater plugs and powerstrips.As you had said cheater plugs are never a good idea.So I geuss that power is power in this case.
Oh yeah, this I know. I was just curious as to which'd last longer and not eff up. So I'll get any strip/cheater plug(if needed) available.

Now, back to the topic.. do the parasounds have a humming issue?
Oh.... durned if I know.
In reply to:

do the parasounds have a humming issue?




I have had a few from the little HCA-750, HCA-1500 and 2205 to my current Halo and with out a doubt the answer is no.....I could also go on about how AC power does make a diff but I have been down this road before on these forums. :-)
Only when they don't know the words.
In reply to:

Only when they don't know the words.




Huh?
He was referring to Thasp's question "...do the parasounds have a humming issue"?

Answer? "only when they don't know the words." (insert rim shot here)
Parasound makes excellent amplifiers. If you're getting a hum out of your system now, there is probably a ground-loop issue or an issue with the way your home or that line was wired.

A used Parasound is a very intelligent way to save a lot of money and end up with a very high quality amp.
Thanks Ajax! I was having a blonde moment! :-)
Ah, don't we ALL have them.
Hmm, just came across this thread.
NH, you may be interested to take a gander at my thoughts on the Halo units way back here.
That is odd to say the least. I have never had a Parasound product hum on me at all. My current HALO has been hush hush since day one. I think in total I have had maybe a total of 8 or 9 Parasound amps and they have all been fantastic and quite! My current HALO has been run through an Onkyo receiver and now my Denon 3805 and it's still dead quite.

I honestly have no explanation why some people hear a hum with these. I have owned more of these then most and have yet to hear a thing.
Come to think of it, the only hum I ever had that I can remember was from a Bryston and that was a ground loop hum which was easily corrected. Parasound, Odyssey, Anthem, Marantz, NAD, ROTEL etc etc etc have all been hum free in my house................but I'm the guy who spent more on the wiring, fuses, box etc etc in my house then most people do. In spite of what some think, I'm a true believer with respect to the power coming in does make a difference on what comes out.

NH, the hum was not a ground loop. The hum was also absent on 3 other amps and two receivers plugged into the same outlet. This issue was definitely related directly to the Halo itself. (Note that in my earlier statement i thought i had related it to a Denon source unit but that was actually ruled out since i broke down and brought my big Onkyo upstairs for use as a preamp.)

If the Halo unit was reacting to something from the power supply in the walls, then its design is flawed but i'm not saying all these Halos do this either. In fact, i wouldn't be surprised if some have it and some don't. I've read at least one other report on the hum but quite some time ago so unfortunately i do not recall which forum it was.
In any event, some problems have been reported with other Halo units such as this lengthy thread on the new units over at The Spot. Concentrate on the posts by Paul Carleton and you will see alot of what i came across. I found this thread just shortly after i took the Halo back from auditioning during my search for answers.
Notice how his use of "power conditioners" did very little to affect the ground loop issues he was having. The ground loops seemed to just move around from item to item but in no way did these conditioners do what they are marketed for. Power from the walls is and always should be regulated by the onboard power supply of the unit. I'm not sure that any electronics piece comes without a power supply that doesn't have regulation onboard. Conditioners are useless. Surge and sag protection are different stories. Bren can tell you all about his pro experience with power from the walls and into the machines over beer until you are blue in the face.

If you continue to read further down, Paul believes he has found the problem (after talking with Parasound), not in the amp but rather in the Halo C1 controller. After reading through this, i started to get concerned about the build quality (back to the design word again) of these Halo units. That is when i started this thread and since gave up on buying the A23.
I now own the Anthem MCA.
Paul summed up my own thoughts quite nicely:
It wasn’t bad but it would be nice on a unit with this price point not to have it at all. It can get pretty bad if you don't have the cable tie that Parasound is now installing on later units. Other than redesigning where the balance inputs go or where the power supply is placed, there is not much else you can do about it.
Again he is referring to the controller but i believe something similar is happening in the amp. I never did take off the lid to see as i knew the unit was going back to the store.
Incidentally, many others have reported no hum whatsover with their Halo units and enjoy them tremendously. If you have another amp, put them together and run them through the same preamp w/o anything playing. Turn up the volume and see if the Halo gets 'louder' either in itself or through the speakers. I had not realized the hum was abnormal until i had it compared to another amp and again i must stress that it was not audible during music playback.
chess, I have seen other reports on the Parasound "Hum" to. Perhaps I have just gotten lucky or something. I can't explain it at all. To me at least Parasound builds nice stuff. I have never had a problem with any of Parasound's products. Not only have I had there amps but for a time when I went completely off the wall I was running the AVC-2500U for a pre. Great pre but when my wife found out what I had into it................I had to sell it. lol
NH, i had my heart set on the Halo. It was the perfect amp for me for features and price. It just fell through because of this oddity and if it were not for the Anthem, i would probably still be searching for an amp today.
Do you know how few amps have any kind of trigger onboard? I really enjoy the auto sensing signal-on function of both the Halo and the Anthem but both also had the more standard 12v trigger as well. Many of the amps i've looked through, several thousand dollars a piece, did not have anything more than a manual on switch. If i wanted to turn my equipment on manually all the time, i would not bother owning remotes!
You would think for several grand the amp companies would put such a simple component into their units so you can turn your system completely on and off from the couch or across the room.
We could start a whole new thread on what I'm about to say but...............I'm one of those folks that never shuts there gear off so I don't use the triggers. Everything I own in HT gear stays on 24/7 except my TV. I can't even remember why I do it anymore but I have done it for years. I have a habit of coming home from work and heading downstairs and thumping a tune. I like the fact that everything is charged up, warm etc all the time.

I'm not real up on Anthem. I may have to try something from them just for $hits & giggles. Pricey or not to bad?

Thread hi-jack in progress.....................
Ah NH, i've covered my thoughts on the 'leaving equipment on' routine many times before.
Of course some will say that it changes the sound, etc. etc., but in all reality it just wastes electricity. Sound be damned, the environment should be the more important consideration.

The Anthems are HIGHLY reasonable in price for what they deliver. Much like many of our purchases {ahem axioms ahem ahem}, we try to find a good value, good quality for prices that do not fall into the audiosnob category, unless the item REALLY has something we like or need. Audiogon has proven to be an amazing resource in looking for equipment since local stores still jack up prices.
The Anthem MCA20 amp was going for $1500 plus taxes at a local shop. I could get it for about $850, less than one year old, on Audiogon. You can see the stats sheets here.
It is really quite a boring aesthetic unit although the silver face does help. For its features and specs, as well as the Anthem build quality and reputation, along with the fact that Anthem is another Canadian company, just sold me.
So far the unit has performed flawlessly, is dead quiet, runs barely luke warm and has plenty of power and headroom for what we paid. They power the big Tannoys just fine.
In reply to:

Ah NH, i've covered my thoughts on the 'leaving equipment on' routine many times before.



Shhh... Manitoba Hydro probably sells extra power there.

Bren R.
I'm doing my part for the power people!
I prefer eating mercury free fish more than i prefer eating power people. You can argue against this but i wouldn't recommend it.

Take it to the politics thread, boys...
In reply to:

Take it to the politics thread, boys...




Noooooooooooooooooooooooooooooooooooo. That is one thread where you will not find me! I have nothing to offer as my views on politics and politicians are straight forward, I can't stand them all. Any of them. Even the ones people think are good. If they are good people they would have never gone into politics etc etc etc. Only good ones are....................it will come to me ????????????????????
In reply to:

Noooooooooooooooooooooooooooooooooooo.



I second that thought.


Political threads on audio forums should be banned and deleted. They pose no use here. Move it over here and be as redneck or as liberal as you want.
In reply to:

Political threads on audio forums should be banned and deleted. They pose no use here.


I'm beginning to agree with you.
I disagree. It keeps things (which are going to be said anyway...) in a separate thread, where those of us who don't want to see it don't have to.
I'm with K. It's going to happen. Consider that we have a lot of people with strong personalities and opinions. We will have opinions on politics and we'll want to discuss them. Preferably with civility. Preventing it from bleeding into battles over speaker break-in and sinusoidal (did I spell that right Bren? ) refraction caused by bad interconnects, but allowing expression is a good idea.

Plus censorship sucks butt.


jr
In reply to:

which are going to be said anyway



That's the point. They shouldn't be brought up in here at all, not if people have enough courtesy for others.
Go discuss political views elsewhere, like in a political forum or in PMs.
This is an audio forum the last i checked. The header does say "Axiom forums", not "United States opinions here please".
Ppl should shove their political statements up their amps and be talking about amps. About as far as it should go is talking about the amp that Bush's daughter just bought.

I'm annoyed at having to screen through 10 posts a minute all about politics. Where the hell are all the posts on audio?
Buried in between.
It's annoying.
If i wanted bad politics i would watch CNN. I come here to read about audio and HT related topics.

Amie, please kill the politics threads. Enough is enough.

In reply to:

I'm annoyed at having to screen through 10 posts a minute all about politics.


Huh? Where's the man with the gun forcing you to screen through the politics posts?
In reply to:

Where's the man with the gun forcing you to screen through the politics posts?




I read the posts using the 'past 24 or 48h' mode so all one sees is a string of posts to the same politics thread, many in a row with SOME audio posts in between.
Frequency varies.
I come here to read about audio, not screen through text subjects like "shooting children in the back."
If i wanted CNN....
A relatively painless alternative that works for me is that the bookmark is set to the index page, showing the five forums. New posts show up in parenthesis. Of course it requires the extra step of entering each forum to see which topics have received replies, but it's okay for me. I'm sure you're well aware of all of this, but I thought I'd mention it. Not my intention at all if this sounds patronizing.

Frankly, I spend an inordinate amount of time here because this is easily one of the most civil, intelligent and good-natured forums out there. I usually learn something, and often get a good laugh. If the off-topic threads are relegated to the Q&C forum and are clearly marked, I don't have a problem with it. And God knows I've been guilty of hijacking a few threads.
chess, I didn't even realize that such a view existed. I can imagine that it's pretty obnoxious to sort through them all and my appologies for that. I have the index page bookmarked as well, and every once in a while when I'm feeling masochistic I open the politics thread. I made it because I was tired of seeing, say, 8 new posts in a thread on speaker placement, only to go in and find some political argument taking place.
In reply to:

tired of seeing, say, 8 new posts in a thread on speaker placement, only to go in and find some political argument taking place



Indeed.
People need to have the courtesy to take it somewhere else more appropriate. This is an audio forum, not a soapbox political derby.

Sorry, Chess, then don't start possibly political arguments in audio threads. I'm afraid we're on two separate sides here. I don't wanna see it, so I say stick it in it's own little thread, since it's going to happen anyway. You don't wanna see it, so you say don't do it.
Ken,
In reply to:

then don't start possibly political arguments in audio threads



Comparing my poke fun comment at NeverH to the ridiculous political thread is like comparing a cookie crumb to the entire Chips Ahoy factory with the Keebler elves inside.

In reply to:

since it's going to happen anyway



If people are courteous enough to not get on their political soapboxes, then it won't just happen anyway. I would like to believe more people here are courteous rather than ignorant.

And if you turn off your electronics thus decreasing the consumption of electricity we WILL see a decrease in the flooding of lands which causes an increased creation in methyl mercury. That is not political propaganda or an individual opinion, it is a fact. Perhaps Neverhappy was unaware of such consequences for leaving electrical items on in the house so i stated such.
Maybe we could move on to turning off an unlit gas stove and putting the handles of boiling pots facing inward as long as you don't ask me to move it to the political thread.

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