Question:
I have an old Hifonics Jupiter VIII 30x4. Currently I am running
infinity 6.5s off 2 of the channels while I search for a center
channel. Will I damage this amp with line level inputs connected to the
2 unused channels with no speakers loaded?

I know a tube amp will fry the output transformer... How about a solid
state circuit? Will I fry mosfets?

thanks,
Garrett

In article ,
Sanitarium wrote:

Question:
I have an old Hifonics Jupiter VIII 30x4. Currently I am running
infinity 6.5s off 2 of the channels while I search for a center
channel. Will I damage this amp with line level inputs connected to the
2 unused channels with no speakers loaded?

I know a tube amp will fry the output transformer... How about a solid
state circuit? Will I fry mosfets?

thanks,
Garrett

It's no problem for it.

"Sanitarium" wrote in message
...
Question:
I have an old Hifonics Jupiter VIII 30x4. Currently I am running
infinity 6.5s off 2 of the channels while I search for a center
channel. Will I damage this amp with line level inputs connected to the
2 unused channels with no speakers loaded?

I know a tube amp will fry the output transformer... How about a solid
state circuit? Will I fry mosfets?

thanks,
Garrett

Some solid state amplifiers can go into thermal
runaway if left unloaded, depends on the design.
I have seen this more in IC output car radios than
any other types.
Jeff

"Jeff" wrote in message
...

"Sanitarium" wrote in message
...
Question:
I have an old Hifonics Jupiter VIII 30x4. Currently I am running
infinity 6.5s off 2 of the channels while I search for a center
channel. Will I damage this amp with line level inputs connected to the
2 unused channels with no speakers loaded?

I know a tube amp will fry the output transformer... How about a solid
state circuit? Will I fry mosfets?

thanks,
Garrett

Some solid state amplifiers can go into thermal
runaway if left unloaded, depends on the design.
I have seen this more in IC output car radios than
any other types.
Jeff



it should be just fine.

"Jeff" wrote in message

Some solid state amplifiers can go into thermal
runaway if left unloaded, depends on the design.

Where would it run to if you had the amp bolted down?
Same reason I keep a leash on my dog when I walk her.

I have seen this more in IC output car radios than
any other types.

I think your dreamin, I have hooked up 1000s of car radios
with only two speakers, leaving the other two speaker leads
unloaded and I have NEVER had any problems, much less
had one RUN AWAY!

If this just a rumor you heard Jeff or an old wives tale or what?


Eddie Runner
installin since 1974
http://www.installer.com/tech/

I too have seen thousands of amps on my service bench diagnosed with no
load attached.
never a problem.
that rumour goes back to early tube days when TUBE amps driven w/o load
did have run away


Jeff wrote:

"Eddie Runner" wrote in message
...
"Jeff" wrote in message

Some solid state amplifiers can go into thermal
runaway if left unloaded, depends on the design.

Where would it run to if you had the amp bolted down?
Same reason I keep a leash on my dog when I walk her.

I have seen this more in IC output car radios than
any other types.

I think your dreamin, I have hooked up 1000s of car radios
with only two speakers, leaving the other two speaker leads
unloaded and I have NEVER had any problems, much less
had one RUN AWAY!

If this just a rumor you heard Jeff or an old wives tale or what?


Eddie Runner
installin since 1974
http://www.installer.com/tech/


Hi Eddie
"No" speakers connected, some amps or ICs will get
hotter and hotter over time. (its rare, not common)
Loading 2 channels of a 4 channel IC is enough to stop
this if it was going to happen. (or 1 of a 2 )
Some companies have a switch to cut signal or turn on
to the outputs if not used.
I have assumed this is why, although it may or may not
be the reason.
I have seen it happen several times on my bench and
had several customers that had bad outputs after a
while of not using them. (no other problems found)
Old car radios are known to have this problem.
No fridge jokes.
Jeff

So have I Chris but I do not mean tube amps and I do
not mean every amp but there are a few that can.
Saying it can not happen ever would be incorrect.
Jeff


"chris lewis" wrote in message
...
I too have seen thousands of amps on my service bench diagnosed with no
load attached.
never a problem.
that rumour goes back to early tube days when TUBE amps driven w/o load
did have run away


Jeff wrote:

"Eddie Runner" wrote in message
...
"Jeff" wrote in message

Some solid state amplifiers can go into thermal
runaway if left unloaded, depends on the design.

Where would it run to if you had the amp bolted down?
Same reason I keep a leash on my dog when I walk her.

I have seen this more in IC output car radios than
any other types.

I think your dreamin, I have hooked up 1000s of car radios
with only two speakers, leaving the other two speaker leads
unloaded and I have NEVER had any problems, much less
had one RUN AWAY!

If this just a rumor you heard Jeff or an old wives tale or what?


Eddie Runner
installin since 1974
http://www.installer.com/tech/


Hi Eddie
"No" speakers connected, some amps or ICs will get
hotter and hotter over time. (its rare, not common)
Loading 2 channels of a 4 channel IC is enough to stop
this if it was going to happen. (or 1 of a 2 )
Some companies have a switch to cut signal or turn on
to the outputs if not used.
I have assumed this is why, although it may or may not
be the reason.
I have seen it happen several times on my bench and
had several customers that had bad outputs after a
while of not using them. (no other problems found)
Old car radios are known to have this problem.
No fridge jokes.
Jeff

Hi Eddie
"No" speakers connected, some amps or ICs will get
hotter and hotter over time. (its rare, not common)
Loading 2 channels of a 4 channel IC is enough to stop
this if it was going to happen. (or 1 of a 2 )
Some companies have a switch to cut signal or turn on
to the outputs if not used.
I have assumed this is why, although it may or may not
be the reason.
I have seen it happen several times on my bench and
had several customers that had bad outputs after a
while of not using them. (no other problems found)
Old car radios are known to have this problem.
No fridge jokes.
Jeff





Sounds like the product of an already efective output chip/transistor. or
the speaker wire is grounding out somewhere.