Does anyone know anything about this integrated amp? I just bought one
after reading some strong reviews and am hoping for the best. It was
an outstanding value so I took a chance. My question is can I leave it
running all the time? It doesn't have a standby mode, but I want to be
able to play music at any time without having to turn it off and on
every time by hand. I don't think the remote controls power.
Alternatively I can connect it through a power source that does have a
remote option, but that's not a great option.

Thanks.

"Dave" wrote in message
...
Does anyone know anything about this integrated amp? I just bought one
after reading some strong reviews and am hoping for the best. It was
an outstanding value so I took a chance. My question is can I leave it
running all the time? It doesn't have a standby mode, but I want to be
able to play music at any time without having to turn it off and on
every time by hand. I don't think the remote controls power.
Alternatively I can connect it through a power source that does have a
remote option, but that's not a great option.

Thanks

Believe it is a tube unit, right? If so, so long as it is well ventilated
you can leave it run, but you'll be replacing output tubes frequently and
all tubes every few thousand hours or so. Just be prepared. If it were me,
I'd turn it on ten minutes before getting ready to listen. I've never had a
tube ampl that took longer than that to warm up and sound good after the
initial tube break-in.

On 10/8/04 1:20 AM, in article , "Harry Lavo"
wrote:

"Dave" wrote in message
...
Does anyone know anything about this integrated amp? I just bought one
after reading some strong reviews and am hoping for the best. It was
an outstanding value so I took a chance. My question is can I leave it
running all the time? It doesn't have a standby mode, but I want to be
able to play music at any time without having to turn it off and on
every time by hand. I don't think the remote controls power.
Alternatively I can connect it through a power source that does have a
remote option, but that's not a great option.

Thanks

Believe it is a tube unit, right? If so, so long as it is well ventilated
you can leave it run, but you'll be replacing output tubes frequently and
all tubes every few thousand hours or so. Just be prepared. If it were me,
I'd turn it on ten minutes before getting ready to listen. I've never had a
tube ampl that took longer than that to warm up and sound good after the
initial tube break-in.

The avaerage time between failure for tubes is usually 5-10x shorter than
most solid state designs - so this is true.

If it has 4 tubes that are under a lot of stress - and the MTBF of any one
tube is 20,000 hours, it would mean that on average you would have 5,000
hours of use before you would have to replace one tube - and if you don't
leave it on all the time, it would last quite a long time! I would watch
out if the tubes glow blue - indications of gas contamination - those tubes,
IIRC tend to fail at a prodigious rate much below my estimate of 20,000
hours for a tube.

This is why the large monoblock amps that use a dozen tubes or more scare
the snot out of me!

B&D wrote:

If it has 4 tubes that are under a lot of stress - and the MTBF of any one
tube is 20,000 hours, it would mean that on average you would have 5,000
hours of use before you would have to replace one tube - and if you don't
leave it on all the time, it would last quite a long time!

There is no single 'rule' for this as different designs use different
percentages of the maximum specified plate dissipation.

I would watch
out if the tubes glow blue - indications of gas contamination - those tubes,
IIRC tend to fail at a prodigious rate much below my estimate of 20,000
hours for a tube.

Not necessarily. Blue glow is often just florescence, and IME, more often than
not.

On 10/10/04 12:05 AM, in article ,
" wrote:

B&D wrote:

If it has 4 tubes that are under a lot of stress - and the MTBF of any one
tube is 20,000 hours, it would mean that on average you would have 5,000
hours of use before you would have to replace one tube - and if you don't
leave it on all the time, it would last quite a long time!

There is no single 'rule' for this as different designs use different
percentages of the maximum specified plate dissipation.

True - I am assuming that the tubes are being used near their ratings. For
power semiconductors, the junction temperature directly influences the MTTF
- every 11 degrees usually doubles the MTTF in that case. I don't know of a
similar rule of thumb for tubes, though no doubt one exists.

I would watch
out if the tubes glow blue - indications of gas contamination - those tubes,
IIRC tend to fail at a prodigious rate much below my estimate of 20,000
hours for a tube.

Not necessarily. Blue glow is often just florescence, and IME, more often
than
not.

Florescence is of a gas - I don't think that gas should be there [hence my
comments about contamination] and from what I have heard about (don't have
any vacuum stuff any more except in a couple of radios) it indicates poor
quality and usually a quicker death of tube.

But, if they have allowed the gas to be there for effect and factored it
into the MTTF, perhaps it doens't affect anything and looks "cool."

B&D wrote:
On 10/10/04 12:05 AM, in article ,
" wrote:

B&D wrote:

If it has 4 tubes that are under a lot of stress - and the MTBF of any one
tube is 20,000 hours, it would mean that on average you would have 5,000
hours of use before you would have to replace one tube - and if you don't
leave it on all the time, it would last quite a long time!

There is no single 'rule' for this as different designs use different
percentages of the maximum specified plate dissipation.

True - I am assuming that the tubes are being used near their ratings. For
power semiconductors, the junction temperature directly influences the MTTF
- every 11 degrees usually doubles the MTTF in that case. I don't know of a
similar rule of thumb for tubes, though no doubt one exists.

I would watch
out if the tubes glow blue - indications of gas contamination - those tubes,
IIRC tend to fail at a prodigious rate much below my estimate of 20,000
hours for a tube.

Not necessarily. Blue glow is often just florescence, and IME, more often
than
not.

Florescence is of a gas - I don't think that gas should be there [hence my
comments about contamination] and from what I have heard about (don't have
any vacuum stuff any more except in a couple of radios) it indicates poor
quality and usually a quicker death of tube.

There is no such thing as a perfect vacuum. One could leave a tube on the
vacuum pump longer, and indeed 'industrial' rated tubes often had this
done. In practical terms, it's all a matter of the gas reaching a point of
'critical mass' so to speak where it becomes a problem in use, making the
tube unstable.

Hallo msacks,

I think we got a bit of track in telling you what you wanted to know.
So if you would lift the upper cover of your new XA-6900
you will discover that it is a hybride amp witch means that he only use
tubes in the preamp section and transistors in the amp section. I think
there only will be 2 smaler tubes inside.
So I wouldn't worry much about leaving it on for a longer time, if you use
him every day annyway.
certanly if you go away for some ore more days you should put him out.

I to want to buy somthing like this amp.
could you tell me were you found some revieuws of it and were to get it at
what price?

Thanks you very much