[Steve[_19_]]

Hey everyone;

I have an ART DPS II "toob" preamp. One of the channels has gone dark
and I would like to try and fix it myself instead of waiting/paying to
get it fixed (not really worth it!). I have done some troublishooting
on the unit and here's some info:

Looking at the signal flow the Mic Input goes to a solid state Mic
Pre, Insturment input goes to a seperate inst mic pre then to the
"Input" meter then to the fake toob stage.

Here are the symptoms:
1. Whether I plug in a insturment or mic, the input meter does not
register.
2. If I crank the input gain and the "toob" meter still registers
(which is wired before the output gain stage)but not the input meter.


I assume the issue is a blown input cap or something. My questions
a

What components can I check to see what is bad on the input?
I could probably replace a cap or resistor but not an IC.

Thanks in advance;
Steve

[Bill Ruys]

What happens if you wiggle the plug around? For some reason the Neutrik
combo jacks on these things seem to go bad very often. If the internal
switch goes bad (which it often does), the symptom can be poor gain. Before
you start pulling other components, I'd check this out first. Is it the
left input that is faulty? This may just be co-incidence, but in my
experience, the left jack often goes bad, even though both left and right
jacks are the same part.

Bill.

"Steve" wrote in message
...
Hey everyone;

I have an ART DPS II "toob" preamp. One of the channels has gone dark
and I would like to try and fix it myself instead of waiting/paying to
get it fixed (not really worth it!). I have done some troublishooting
on the unit and here's some info:

Looking at the signal flow the Mic Input goes to a solid state Mic
Pre, Insturment input goes to a seperate inst mic pre then to the
"Input" meter then to the fake toob stage.

Here are the symptoms:
1. Whether I plug in a insturment or mic, the input meter does not
register.
2. If I crank the input gain and the "toob" meter still registers
(which is wired before the output gain stage)but not the input meter.


I assume the issue is a blown input cap or something. My questions
a

What components can I check to see what is bad on the input?
I could probably replace a cap or resistor but not an IC.

Thanks in advance;
Steve





** Posted from http://www.teranews.com **

[Steve[_3_]]

Tried that. No dice. It's the right (channel 2) input. I have also tried
using the jacks at the back of the unit with the same result.

Thanks for the tips.

Cheers;
Steve
"Bill Ruys" wrote in message
...
What happens if you wiggle the plug around? For some reason the Neutrik
combo jacks on these things seem to go bad very often. If the internal
switch goes bad (which it often does), the symptom can be poor gain.
Before you start pulling other components, I'd check this out first. Is
it the left input that is faulty? This may just be co-incidence, but in
my experience, the left jack often goes bad, even though both left and
right jacks are the same part.

Bill.

"Steve" wrote in message
...
Hey everyone;

I have an ART DPS II "toob" preamp. One of the channels has gone dark
and I would like to try and fix it myself instead of waiting/paying to
get it fixed (not really worth it!). I have done some troublishooting
on the unit and here's some info:

Looking at the signal flow the Mic Input goes to a solid state Mic
Pre, Insturment input goes to a seperate inst mic pre then to the
"Input" meter then to the fake toob stage.

Here are the symptoms:
1. Whether I plug in a insturment or mic, the input meter does not
register.
2. If I crank the input gain and the "toob" meter still registers
(which is wired before the output gain stage)but not the input meter.


I assume the issue is a blown input cap or something. My questions
a

What components can I check to see what is bad on the input?
I could probably replace a cap or resistor but not an IC.

Thanks in advance;
Steve





** Posted from http://www.teranews.com **

[Robin G]

Maybe the same problem I had on my piece?

But first, what is fake about the tube stage? (apart from the "design
for the suckers" orange LED enlightment of the tube)

And, second, the input meter is wired before your "toob" meter and of
course also before the tube stage.

But anyway, the input meter is located on a separate board mounted
above the VU meter. Try wigling it, my card had some bad connection
with the motherbord and lit up when I did.

And also, while you have the lid of, check that the power cables to
the frontpanel switch is as far away as possible from the left input
stage...

Good luck!
Robin

[Steve[_3_]]

"Robin G" wrote in message
...
Maybe the same problem I had on my piece?

But first, what is fake about the tube stage?

It's a "starved plate design". Older tube equipment used to run the tube
plates at 300+ Volts. The new fake "toob" stuff uses more like 24 Volts to
simulate that warm sound (which is not really the sound it used to sound
like).

(apart from the "design
for the suckers" orange LED enlightment of the tube)

Exactly. Pump 300+ volts through just about anything and it will glow
orange with minimal assistance. :-)


And, second, the input meter is wired before your "toob" meter and of
course also before the tube stage.

I understood that.


But anyway, the input meter is located on a separate board mounted
above the VU meter. Try wigling it, my card had some bad connection
with the motherbord and lit up when I did.

I did. It did nothing. I found when I touched it in some places the meter
pegged (the tube meter did nothing, I assume I was connecting the supply
voltage to that PCB to the meter with my finger).


And also, while you have the lid of, check that the power cables to
the frontpanel switch is as far away as possible from the left input
stage...

Checked all connections and made sure everything was okay. Thanks for the
help! :-)

Cheers;
Steve


Good luck!
Robin