Reliability

[Guest]

Archived from groups: rec.audio.high-end (More info?)

What the heck is with reliability in high-end amps? I have
had three high power, solid state amps over the last 15 years
or so.

Brand "A" never required repair, but it did have an audible
mechanical hum that I countered by putting the amp into an
equipment cabinet, on a foam pad.

Its replacement in my system, brand "C", had better sound but
also had an audible hum. It took me a while to realize that
it ran hot enough that it couldn't go into the cabinet. It
went back to the manufacturer three times, twice
(unsuccessfully) to have the hum reduced, and a third time
when its power switch failed.

Now I am using brand "B". This has NO mechanical or
electrical noise that I can hear while it's running. However,
it's had to go back to the manufacturer twice for unsettling
turn-on or turn-off noises (clicks, hums, and so on). To take
the cake, it weighs about 90 lb (41 kg), so it's expensive and
unwieldy to ship, even though the repairs are under warranty.

None of the above are garage firms.

This phenomenon is not limited to amps. I have seen expensive
CD players that mistracked many discs. Another CD player had
a mechanical hum audible from the listening position. For
some reason, I've never had trouble with a preamp. Even
TURNTABLES have been more reliable for me than amplifiers.

What amplifier manufacturers can folks recommend that are good
sounding and RELIABLE? No tubes, please -- I live in heavy
air-conditioning territory & I can't deal with the heat.


Mike Prager
North Carolina, USA

 

[Guest]

Archived from groups: rec.audio.high-end (More info?)

Mike Prager wrote:

> What amplifier manufacturers can folks recommend that are good
> sounding and RELIABLE? No tubes, please -- I live in heavy
> air-conditioning territory & I can't deal with the heat.

I run Hafler power amps. I have four of them because I
multi-amp my speakers. They've been bullet-proof since
the day I bought them.

Hafler only makes pro-grade amps these days. I bought
them for a number of reasons.

1. They rack mount and thus take up less space. I rack mount
all my stuff and it takes up a fraction of the space my old
setup did.

2. They're air-cooled. Most pro-grade amps have fans and
that's a no-no for us audiphiles.

3. They're MOSFET amps and have that characteristic MOSFET
sound which is rather tube-like. It's a sound characteristic
that I personally like.

4. Pro-grade amps are built to take signal abuse. Not that
I do that to amps, but there have been occaisions where I did
something stupid accidentally and have fried an amp in the past.
Pro-grade amps are engineered to survive such idiocy.

I strongly recommend a Hafler amp if you're running electrostatic
speakers for example. They can manage those weird loads.

You asked about reliability. That's what distinguishes a
pro-grade amp from a home use amp. The pro-grade stuff is
engineered to withstand being hauled around and subjected
to signal abuse.

http/www.hafler.com/

Russ Button

 

[Guest]

Archived from groups: rec.audio.high-end (More info?)

"Mike Prager" <hifi@ec.rr.com> wrote in message
news:d5iibl02toi@news2.newsguy.com...
> What the heck is with reliability in high-end amps? I have
> had three high power, solid state amps over the last 15 years
> or so.
>
> Brand "A" never required repair, but it did have an audible
> mechanical hum that I countered by putting the amp into an
> equipment cabinet, on a foam pad.
>
> Its replacement in my system, brand "C", had better sound but
> also had an audible hum. It took me a while to realize that
> it ran hot enough that it couldn't go into the cabinet. It
> went back to the manufacturer three times, twice
> (unsuccessfully) to have the hum reduced, and a third time
> when its power switch failed.
>
> Now I am using brand "B". This has NO mechanical or
> electrical noise that I can hear while it's running. However,
> it's had to go back to the manufacturer twice for unsettling
> turn-on or turn-off noises (clicks, hums, and so on). To take
> the cake, it weighs about 90 lb (41 kg), so it's expensive and
> unwieldy to ship, even though the repairs are under warranty.
>
> None of the above are garage firms.
>
> This phenomenon is not limited to amps. I have seen expensive
> CD players that mistracked many discs. Another CD player had
> a mechanical hum audible from the listening position. For
> some reason, I've never had trouble with a preamp. Even
> TURNTABLES have been more reliable for me than amplifiers.
>
> What amplifier manufacturers can folks recommend that are good
> sounding and RELIABLE? No tubes, please -- I live in heavy
> air-conditioning territory & I can't deal with the heat.

Ever checked your line voltage? A sagging line voltage due to a bad
connection somewhere in your wiring will put a load on your amps power
transformer possibly aggravating their tendency to make an mechanical hum.
2 amps and a CD player having mechanical hum would lead me to look for a
common cause.

ScottW

 

[Guest]

Archived from groups: rec.audio.high-end (More info?)

Mike Prager wrote:
>
> What amplifier manufacturers can folks recommend that are good
> sounding and RELIABLE? No tubes, please -- I live in heavy
> air-conditioning territory & I can't deal with the heat.

Bryston. I've had the same 3B amp and .5B preamp for over 20 years, no
problems. Although they initially came with a 5 year warranty, several
years after purchase I was informed that my warranty had been extended
to 20 years. What other manufacturer has that kind of confidence in
their product? They all still come with 20 year warranties that are
scrupulously honoured. Furthermore, they provide prompt answers to
technical questions by email. Bryston products are built like tanks,
backed to the hilt by the factory and they sound great, IMNSHO. Buy
with confidence.

Neil

 

[Guest]

Archived from groups: rec.audio.high-end (More info?)

ScottW wrote:

> Ever checked your line voltage? A sagging line voltage due to a bad
> connection somewhere in your wiring will put a load on your amps power
> transformer possibly aggravating their tendency to make an mechanical hum.
> 2 amps and a CD player having mechanical hum would lead me to look for a
> common cause.

Thanks for the idea. The latest incident was indeed a
line-voltage problem during bad weather. Brand "B" can be
cleared of the charge of needing excessive repairs.

I did check line voltage when I used the other gear, and it
was normal. For part of that time I used a Tripplite line
voltage regulator, which I got rid of because IT made a hum.


Mike Prager
North Carolina, USA

 

[Guest]

Archived from groups: rec.audio.high-end (More info?)

Neil Gendzwill wrote:

> Bryston. I've had the same 3B amp and .5B preamp for over 20 years, no
> problems.

Glad to hear you have had such good results. Thanks for the
suggestion.

Mike Prager
North Carolina, USA

 

[Tip]

Archived from groups: rec.audio.high-end (More info?)

Hi Mike,

"Mike Prager" <hifi@ec.rr.com> wrote in message
news:d5rj77024mg@news1.newsguy.com...
> I did check line voltage when I used the other gear,
> and it
> was normal. For part of that time I used a Tripplite
> line
> voltage regulator, which I got rid of because IT made
> a hum.

You may have a DC offset in your AC power. PS Audio
makes a device called a "Hum Buster" that removes the
DC from the AC, which may be causing the hum in the
transformers. I tried one, and it did remove the hum
from some transformers, but not others. It has a free
trial period, so I was able to return it and get my
money back.

I have a MIT Z-Center power conditioner that had a hum
on the transformers for the isolated outlets (isn't it
ironic?). I ended up bypassing the transformers and
giving up the isolation (which wasn't really needed) to
get rid of the hum.

Regards,
Tip