i've got this Fostex DE-1 dual fx little half U thing
that i found in a cashconverter shop.
the guy offered me a PSU for it, i said no thanks,
seeing it was AC, not DC like on the box (gotta be
a bit dumb doing that if you work in a place like that!?)
anyway, so i finally found a PSU with the 9v DC 600mA
it wants, and with the smaller connector as on the unit.
i was getting just glitchy noise through it with 500mA,
so i hoped i was just a lack of current, but it's still a
messy disaster with the correct PSU...so, (dumb)question:
can this thing have been damaged by the wrong PSU
these guys offered me?(i've had it kicking around for
too long to take it back now...) - what would fry, if
it was getting AC ?? (off the top of your head...)
it's a pretty basic multifx with delay/verb/chorus/flanger/etc.
selector knob plus 'adjust param' knob, that kind of thing. notable
feature is that it's a dual unit in a half rack(2 stereo outs for the
2x mono/L-R inputs) that can be configured as two separate parallel
units, or chained in series:
here it is:
http://www.soundonsound.com/sos/dec99/a ... ntials.htm
quite a nice looking compact shallow unit, and i'm curious to see if
i have any use for it. not much to see inside, i'll take some photos
in a bit when i open it. if anything, i can sell it if i can fix it and
don't need it. any help most appreciated!
can 9v AC cause damage to a device wanting 9v DC?
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- KVRAF
- Topic Starter
- 3166 posts since 13 Jun, 2004
ps: the leds come on, one green 'on', and 2 red 'peak'. all are
on when i power it at first, with the peak indicators going off
after eg: 1 second
no noise when 'dry', but noisy flanged beats when 'wet'. depending
on setting.some become full-on glitch madness. not in a useable way!
well it is noisy anyway...i guess it could do vinyl scratches on things
but that's bit limited. i can't recognise any reverbs or delays in there,
it's a bit like bad ringmodulation. and i have to turn the gain right up
to get a signal(there are pots at the back for each input)
in fact i'm starting to recognise the fx, delays, flange etc. but it is mostly
ringmodded and scratchy/glitchy. most of it seems to work.
there's a brief pause as fx selection is changed.
seem to be getting signal going through to #2 from either input, even in 'dual'
mode (single/dual > serial/stereo-parallel)(but this doesn't seem to be working
predictably)
it could be something quite simple, or maybe s'thing important.
(can i damage anything plugged into it, audio source?)
edit: aw sh*t, it is still a 500mA...tiny letters, thought it was 600..
(so is there hope for it yet...?)
on when i power it at first, with the peak indicators going off
after eg: 1 second
no noise when 'dry', but noisy flanged beats when 'wet'. depending
on setting.some become full-on glitch madness. not in a useable way!
well it is noisy anyway...i guess it could do vinyl scratches on things
but that's bit limited. i can't recognise any reverbs or delays in there,
it's a bit like bad ringmodulation. and i have to turn the gain right up
to get a signal(there are pots at the back for each input)
in fact i'm starting to recognise the fx, delays, flange etc. but it is mostly
ringmodded and scratchy/glitchy. most of it seems to work.
there's a brief pause as fx selection is changed.
seem to be getting signal going through to #2 from either input, even in 'dual'
mode (single/dual > serial/stereo-parallel)(but this doesn't seem to be working
predictably)
it could be something quite simple, or maybe s'thing important.
(can i damage anything plugged into it, audio source?)
edit: aw sh*t, it is still a 500mA...tiny letters, thought it was 600..
(so is there hope for it yet...?)
-
- KVRAF
- 15516 posts since 13 Oct, 2009
The answer to your question is yes, it can. Of course you know that polarity of a DC adapter is very important, as is voltage.
Voltage: (V, volts)
Power supply lower than device, probably not a problem, it just won't work, but is unlikely to cause damage
Power supply within 5% high or low of device, usually not a problem, device will usually work.
Power supply up to 20% higher than device, bad idea, but it probably won't blow up, don't call me if it does, but for some devices this wouldn't stress me out.
Power supply more than 20% higher than device, high probability of causing damage, don't even plug it in.
Current: (mA, milliamps, or A amps, 1000mA=1A)
Power supply lower than device, probably won't work, but, can potentially cause damage to power supply. This may, in turn, risk the device, but the chances are low. Still, it's a bad idea, the power supply may overheat, can even cause a fire.
Power supply within 5% of device rating, probably no problem at all, just use it, make sure that if the supply is lower than the device that you keep an eye on how hot the power supply gets.
Power supply higher than the device, this is not a problem but really confuses some people. The supply has more capacity than the device needs, but, the device will only draw what it needs. Do not worry about the current being higher than the device's needs, it will work fine.
AC vs DC and DC Polarity
Power supply AC, Device DC, can cause problems, don't plug in, even for a second.
Power supply DC, device AC, depending on device, may or may not work, doesn't usually cause problems, but can. Best to avoid completely.
Power supply Center +, device Center -, can cause immediate damage, do not plug in for even a second
Power supply Center -, device Center +, can cause immediate damage, do not plug in for even a second
Voltage: (V, volts)
Power supply lower than device, probably not a problem, it just won't work, but is unlikely to cause damage
Power supply within 5% high or low of device, usually not a problem, device will usually work.
Power supply up to 20% higher than device, bad idea, but it probably won't blow up, don't call me if it does, but for some devices this wouldn't stress me out.
Power supply more than 20% higher than device, high probability of causing damage, don't even plug it in.
Current: (mA, milliamps, or A amps, 1000mA=1A)
Power supply lower than device, probably won't work, but, can potentially cause damage to power supply. This may, in turn, risk the device, but the chances are low. Still, it's a bad idea, the power supply may overheat, can even cause a fire.
Power supply within 5% of device rating, probably no problem at all, just use it, make sure that if the supply is lower than the device that you keep an eye on how hot the power supply gets.
Power supply higher than the device, this is not a problem but really confuses some people. The supply has more capacity than the device needs, but, the device will only draw what it needs. Do not worry about the current being higher than the device's needs, it will work fine.
AC vs DC and DC Polarity
Power supply AC, Device DC, can cause problems, don't plug in, even for a second.
Power supply DC, device AC, depending on device, may or may not work, doesn't usually cause problems, but can. Best to avoid completely.
Power supply Center +, device Center -, can cause immediate damage, do not plug in for even a second
Power supply Center -, device Center +, can cause immediate damage, do not plug in for even a second
Last edited by ghettosynth on Thu May 29, 2014 5:59 pm, edited 2 times in total.
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- KVRAF
- 15516 posts since 13 Oct, 2009
-
- KVRAF
- 6113 posts since 7 Jan, 2005 from Corporate States of America
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- KVRAF
- Topic Starter
- 3166 posts since 13 Jun, 2004
yes, thanks ghettosynth! worth quoting whenever the issue comes up.
so: does this mean damage to a 'first line' device? i guess not necessarily,
depending on the circuit, but maybe the first sensitive thing the voltage
will come to, huh..
example: i have a Boss RPS-10, you know those old half U fx - and they
had the bonzer idea of putting a thru DC connector right next to the in
DC... so, i dunno: did i accidentally stick the *proper* Boss 9vDC centre negative
adaptor on the thru? or was it fffff'd before it arrived (bbadddly packed in post,
in original box with RDD-10, no padding, miracle it arrived at all, or that either
wasn't mashed up - the RDD-10 works, kinda wish it was the other way round)
whichever, the rps10 now has mega low volume, evidence that all functions
work behind the grizzle+low audio level. i'm wondering if there just some
short in the plug(to ground?) or if there's a fault in the input path. no techs
round here, and i can't justify large costs on this unit.
the same sort of behaviour from the DE-1(hey some top units here, not! - but
it'd be nice to have them working, even if only to flog them on if i have no
use for them - they both nice little things that can find a home easily)
seems like the same fault in both. tchaaa, those prats at the cashconvert
place, trying to hand me the AC adapter, getting snotty about demo-ing it,
etc. and now that place is 30 miles away ;- / so i never took it back within
return period..pfff
with the rps, any ballpark idea what could have gone on it? @ 70eu/hr i'm
not keen to take it to the chinese guy..
so: does this mean damage to a 'first line' device? i guess not necessarily,
depending on the circuit, but maybe the first sensitive thing the voltage
will come to, huh..
example: i have a Boss RPS-10, you know those old half U fx - and they
had the bonzer idea of putting a thru DC connector right next to the in
DC... so, i dunno: did i accidentally stick the *proper* Boss 9vDC centre negative
adaptor on the thru? or was it fffff'd before it arrived (bbadddly packed in post,
in original box with RDD-10, no padding, miracle it arrived at all, or that either
wasn't mashed up - the RDD-10 works, kinda wish it was the other way round)
whichever, the rps10 now has mega low volume, evidence that all functions
work behind the grizzle+low audio level. i'm wondering if there just some
short in the plug(to ground?) or if there's a fault in the input path. no techs
round here, and i can't justify large costs on this unit.
the same sort of behaviour from the DE-1(hey some top units here, not! - but
it'd be nice to have them working, even if only to flog them on if i have no
use for them - they both nice little things that can find a home easily)
seems like the same fault in both. tchaaa, those prats at the cashconvert
place, trying to hand me the AC adapter, getting snotty about demo-ing it,
etc. and now that place is 30 miles away ;- / so i never took it back within
return period..pfff
with the rps, any ballpark idea what could have gone on it? @ 70eu/hr i'm
not keen to take it to the chinese guy..
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- KVRAF
- 1702 posts since 26 Feb, 2008
Yes, if there were no diodes offering reverse input protection then it absolutely would have fried the product.
On the voltage side of things if you have the dc polarity right, meh... most 9v products have regulation that will cover up to about 18v inputs honestly. I wouldn't really recommend pushing it but a low-current device that immediately breaks with a little dc over-voltage was probably designed like a piece of shit anyway honestly.
On the voltage side of things if you have the dc polarity right, meh... most 9v products have regulation that will cover up to about 18v inputs honestly. I wouldn't really recommend pushing it but a low-current device that immediately breaks with a little dc over-voltage was probably designed like a piece of shit anyway honestly.
Snare drums samples: the new and improved "dither algo"
