2. amps-preamps
  3. 148006-93722

Power Amp advice

I am looking for advice on a power amp to drive my Magnepan 1.7i's.  My source is my Cambridge Network player which I use to stream Tidal.  My preamp is Tube unit: Transcend 6SN7 Line Stage by Aric Audio.  My current amp is a Parasound HCA2200.  The Parasound has lately developed an annoying hum.  I was thinking of getting it repaired, but thought that now might be a good time to upgrade that 30 year old piece.

I was looking for advice on a good match for the preamp/speaker combination.  My budget is around $2,000.  I don't mind buying used.  I was thinking to go with tubes, but I fear that any tube amp with enough oomph to properly drive those Maggies would be well outside of my budget.

Discussions here are always thoughtful, so I am looking forward to what you folks have to share.

Thanks,
Mark 
128x128markainsworth
rikkipuu's avatar
rikkipuu
245 posts
 
Personally I went from a beastly class D to a Pass XA60.8 for my 3.7i's.  The sound is sweet as long as I dont play LOUD.  My room is over 500 square feet.  Quality over quantity every time.
I found this at the review below, maybe you can save the Parasound.
http://www.audioreview.com/product/amplification/amplifiers/parasound/hca-2200ii.html
[May 17, 2007]greasemonkeyAudioPhile
STRENGTH:

The amp delivers a powerful and clear sound. It is only seconded only by my favorite amp the BA-5000 from Sansui. Great design carried out with quality components.

WEAKNESS:

The initial hum caused by a floating ground condition.

I picked up a HCA-2200 II from ebay a few years ago. I also had the same problem with a 60 cycle hum which came out of one channel only. I decided to explore the problem internally after trying the ungrounded plug adaptor trick which only minimized the hum slightly. What I found was that almost every screw either internally but especially externally in the case was loose. They were loose enough that you could turn them by hand. So, I checked each fastener and tightened down every loose one. That one thing eliminated the hum completely. I could only guess that the problem was from a floating ground condition. I can only surmise that the fasteners were not torqued down to a reasonable amount during assembly at the factory and over the years they continued to back out by themselves due to vibration.
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markainsworth's avatar
markainsworth OP
92 posts
 
Thanks anzaanimalclinic. The folks at audioreview all said the amp hummed when they received it. Mine was absolutely silent for a year (I bought it used on e-bay for $400). I will give the cheater plug treatment a try even though that seems wrong to me. Maybe that emulates ’floating’ the signal ground.

BTW I have had the top off so all of the exterior screws are tight.


markainsworth's avatar
markainsworth OP
92 posts
 
Blissful silence

It has been a long time since I have lived in a house that had any two pronged receptacles, so cheater plugs are in short supply.  Not so unused IEC power cords.  So I cut off the ground prong on one of them.  No luck  Still, it was worth a shot.
Reading some more of the reviews, one of the reviewers indicated that a tech at Parasound suggested tightening the screws on the transistors.  Though none of them seemed loose, I made sure they were torqued down pretty solid.
Problem solved.  Thanks again anzaanimalclinic.  (and to Joe at audioreview).


markainsworth's avatar
markainsworth OP
92 posts
 
LOL  After a few minutes the hum is back.  Not as loud as before, but still annoying.
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