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Topic: Noisy Stroboflip Power Supply |
Bob Sykes
From:
North Carolina
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Posted 9 Nov 2010 7:35 pm |
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I recently bought a Stroboflip tuner and I am thrilled with it, however the included AC power supply is NOISY. It's a switcher made by Globtek with the largest ferrite bead I've seen on a wall-wart. If you have one of these and are experiencing noise problems through your guitar rig or anything else plugged into the same branch circuit, unplug the DC connector on the side of the Strobflip and see if the noise goes away. Here's what the nois maker looks like. I hope this tip might be useful to someone sometime....
I may take this thing to work and measure the noise it emits. I will certainly replace it with a quieter unit. In my other life I'm an EMC (electro-magnetic-compatibility) Engineer. I work extensively with electrical noise.
_________________
Carters Starter, D10 8+7, SD10, Chandler RH-2, Rogue RLS-1
ISO Sustainus Ad Infinitum |
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Billy Murdoch
From:
Glasgow, Scotland, U.K.
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Posted 10 Nov 2010 12:26 am
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Bob,
I have had a 'Flip for a few years and never used the power supply.The batteries last for a long time and I get a dimming of the display which indicates(in good time)the need for battery replacement.
I find there is little,or nothing to be gained by using the power supply.
Best regards
Billy
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Jack Stoner
From:
Kansas City, MO
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Posted 10 Nov 2010 3:25 am
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It must be a defective unit. Mine does not have any "noise" and I can place the tuner with the external power cord connected on the strings of one neck and tune the other and there is no interference. I've only used it once in line and there was no noise, hum, etc.
I'm very critical of equipment and sound, as I am an electronics tech and former amp repair tech.
However, I only use it with the AC power supply at home, on jobs I only use the internal batteries. |
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Bob Sykes
From:
North Carolina
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Posted 10 Nov 2010 7:22 pm
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I'll have to try using batteries. I have always used an AC adapter with my previous tuners. This particular one seems to putting noise out on the AC side. So an amplifier (for example) plugged into the same power strip will exhibit the noise. This past weekend, I took my power from the monitor mixer rack. Big mistake, but I knew what to unplug to fix the problem. I'm not using the tuner in line, it's got its own feed from the volume pedal. I like to leave the tuner on all the time on a gig. If this one will work for a reasonable length of time with some rechargeables, that would be one less cable to get in the way.
_________________
Carters Starter, D10 8+7, SD10, Chandler RH-2, Rogue RLS-1
ISO Sustainus Ad Infinitum |
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Kevin Mincke
From:
Farmington, MN (Twin Cities-South Metro) USA
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Dan Johnson
From:
Texas, USA
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Posted 15 Nov 2010 8:25 pm I have had this happen to me
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| This sounds crazy but I solved this by using a volume pedal with a tuner out, also the effects unit by digitech genesis 3 fixed it . |
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Bob Sykes
From:
North Carolina
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Posted 19 Dec 2010 8:36 pm Figured it out
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The power supply connects the AC ground pin to DC ground which in turn is connected to the shield of the tuner audio input. Loopy ground = buzz. Solution = AC ground lift "cheater" adapter. Problem solved. Batteries worked well too but I like that blue LED lighting.
_________________
Carters Starter, D10 8+7, SD10, Chandler RH-2, Rogue RLS-1
ISO Sustainus Ad Infinitum |
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Ken Fox
From:
Nashville GA USA
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Posted 20 Dec 2010 5:18 am
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| Good trouble shooting. They should never have used a power supply that does what this one does. A class 2, power limited supply has no need to have it's output associated with earth ground, period. A true Class 2 power supply is,limited by NEC to 100VA and is "inheriently currently limited", meaning a dead short will blow it out and it is does not have a user replaceable fuse. Interesting that this little Chinese supply does not state the class of operation. |
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Jack Stoner
From:
Kansas City, MO
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Posted 20 Dec 2010 6:38 am
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I normally do leave my Strobe O Flip in line and only use it with batteries on a job, but at home sometimes I will do that with the AC adapter. I don't have any hum or any "ground loop hum" using the supplied AC power supply.
It is grounded the same way as yours - the AC power ground is connected to the DC power ground.
My setup at home is Guitar (with Lawrence 710 pickups) to the tuner, from the tuner to the input of a Hilton Volume Pedal, from the Volume pedal direct to a Peavey Nashville 1000 or from the Volume Pedal to a POD XT and then to the Nashville 1000 amp. |
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Ken Fox
From:
Nashville GA USA
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Posted 20 Dec 2010 7:00 am
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As a low voltage electrician (retired) I have been out of the loop a few years on the more modern supplies. This supply may well be grounded as part of it's protection as well as noise filter. This is a computer style supply and I can see where the ground would help reduce noise to a laptop or other device.
Maybe not the best choice for this application, as the ground does cause a ground loop hum. |
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Greg Cutshaw
From:
Corry, PA, USA
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Posted 20 Dec 2010 9:41 am
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My stroboflip does not impart any noise onto the AC line or other devices altho I don't doubt that your's does. I've also noticed that my Flip gives quite a bit more stable reading on AC power than it does on batteries, even fresh ones. It's a great device but not perfect. You get a slightly sharp reading on these with a strong input signal so use the strobe reading obtained when the input signal almost dies off and it seems to leave all the instruments in tine with each other. Lot's of quirks but still the best tuner I've ever had.
You could try a well filtered analog power supply on the Flip. This might solve the ground loop problem and eliminate any possible supply switching noise. \
Greg |
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Jim Sliff
From:
Lawndale California, USA
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Posted 20 Dec 2010 10:08 am
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I don't think I've posted this here - it's a copy-and-paste (with a few edits) of info I give players who email me about power supply issues. As with Ken (since we seem to usually tag-team 'bout 90% of the stuff in the Electronics section!) I've rarely seen a class 2 supply that didn't have the class printed on it - I wonder if that's the original adapter?
Anyway, since I've found most players don't know much about effect power supplies (just us guys suffering from far too much solder inhalation) here's a little bit about "wall wart" power supplies (in VERY BASIC LAYMAN'S TERMS - please, no flames from the tech group - this is for the player, not the tinkerer):
90% of the aftermarket power supplies you find at Radio Shack, Garage Sales, Swap Meets,leftover from telephones and other gadgets etc are NOT appropriate for effects pedals (or tuners).
First, any 9VAC power supply you find left over from one of the 50 cordless phones you've tossed out - TOSS OUT. Just about every pedal runs on DC, not AC (there ARE exceptions - and there are also exceptions that are NOT exceptions - confused? read on...).
Any 9VDC power supply from a phone, tool recharger or anything BUT a piece of audio equipment you can probably toss out.
We'll start with 9 volt adapters ("wall wart" the common term due to the lump of plastic that always seems to take up more room on a power-strip than you want!). There are basically two types: 1) non-regulated, and 2) regulated (or "switching"). Switching DOES NOT mean it has a switch on it - in fact the ones you see with switches (and usually an assortment of tips) that allow you to change the voltage are NOT "switching" supplies!
I know, I know...but it only gets worse. 
Regulated supplies normally (and there is some variation in this) put out about 9.6 VDC with no pedal hooked up. This higher voltage allows them to sag to the correct 9VDC when under load (i.e. hooked to one or more pedals...more on that in a sec).
SOME regulated supplies may run up to 11 volts - but you can be pretty sure anything listed as a 9VDC supply that puts out more than 11 (usually 14) volts DC is not a regulated supply.
A typical 9VDC supply might be rated for 200ma (the usual number you see) or anything up to 1200ma or more. Those numbers are WAY over the usual pedal requirements, and most can power more than one pedal. "Swirly" (Chorus and Flanger) and delay pedals draw more juice than overdrive, fuzz and distortion pedals, by the way - a typical fuzz might only draw single-digit ma (the ZVex Fuzz Factory, for example, can run on ONE cheap carbon 9V battery for years - with a guitar plugged in!
BOSS (which is used as the standard when comparing types) make several power supplies, and their terminology is used as the standard when talking about 9-volt DC units: the PSA-120, a 9VDC, switching/regulated supply that is the same type used by most 9VDC pedals on the planet, and the ACA non-regulated unit (that will measure around 14 volts on a multimeter) that is used with several 1990's/earlier pedals such as the Touch Wah. That one is a good example - use an ACA adapter OR hook it up to a One Spot's 5 or 8 plug daisy chain with PSA pedals and it's quiet; hook it up to a BOSS PSA-120 regulated adapter and it'll hum like mad.
This can drive players who are not aware of it CRAZY.
It also causes a lot of "broken" pedals to be sold cheaply. Heck, how do you think I got all my ACA pedals? 
Just forget the high-school electronics theory - it'll work - even though you can't power two ACA pedals from ONE ACA wall-wart!
Huh?
Yep - you CAN power two from the right kind of PSA adapter...but not from the same ACA adapter, even though they are ACA-type pedals.
SOME pedals - mostly fuzz and some Yamaha units - are "reverse polarity - PSA and ACA adapters are center-negative; reverse polarity is center-positive. Visual Sound makes 3" adapters that sell for $3-5 that simply reverse the polarity. BUT be careful, some pedals don't like reverse power and can be damaged.
Ready for the Tylenol yet?
Anyone own a Line-6 Modeling pedal? The big ones with 4 switches, like the DL4 Delay Modeler? Right by the power-supply input it says "9VAC". Yes, **AC**.
But with a little adapter cable that fits the One Spot (and other multi-pedal supplies) you can hook it up to the daisy-chain.
But isn't the daisy chain **DC**? AND doesn't the DL4 say AC AND something like 1200ma? Don't I need my tech on speed-dial?
Nope.
Look at your DL4 (or MM4, or whatever) - when did you last put batteries in it? And were those batteries **AC** batteries?
Nope. Because the thing runs on DC. Tricky, huh? And it ALSO does NOT "draw" 1200, or 2000ma or whatever it says.
But-
NEVER plug an AC-output wall wart (like a 9VAC unit) into a DC pedal of ANY kind or you WILL fry it. Also, never plug an 18VDC wall wart into MOST effects or you'll cook them (there are exceptions - and I WILL NOT tell you what they are, as you should ALWAYS be absolutely certain it'll work by contacting the manufacturer)
Voice of experience - I've been working with this stuff for almost 45 years and I color-code my adapters; blue vinyl tape around all PSA types, red on all ACA types and striped tape on AC adapters (which might be 10VAC, 9VAC, 18VAC). If I have NO marking it's an oddball - an odd voltage, usually-AC adapter made for ONE effects unit.
I go a few loose adapters at an electronics swap. I left them in the wrong place. And picked up a 9VDC, regulated adapter and plugged it onto my beloved MXR Phase 90.
The light sure looked cool for the 1.5 seconds of REALLY bright light before it made a "BZZZZT" noise.
18VAC.
Crap.
And I HATE replacing integrated circuits more than any other electronics job.
It's fixed and EVERYTHING is marked.
Last notes - PSA and ACA adapters plugged into each other's pedals won't hurt anything, but the hum will be horrid (Except for ACA pedals in a daisy chain with PSA pedals powered by a One Spot of similar). 9VDC adapters plugged into Line-6 "AC" pedals are fine.
But other than that, the general rule is DO NOT make a mistake intermixing pedals.
Now - go find every multiple-voltage switch, interchangeable-tip, unmarked-class, telephone, answering machine, clock radio, tool charging and other wall-wart not SPECIFICALLY used for the named item, cut the small plug off and THROW IT AWAY (the ends are handy for semi-permanent pedalboard wiring).
If you don't toss them out you WILL either screw up and burn up a pedal or mistakenly use one when hurrying to a gig, get there and find out you can't use your favorite death-metal grind pedal because of the hum.
Sidebar - also, NEVER run electrical power (extension cord, wall-wart wires etc) next to signal cables (guitar cables or speaker wires) Always keep them at least 6 inches apart, more if possible - NEVER strap the together - a common cause of hum.
Hope that helps. And I recommend if you use multiple effects) a single power supply except for those pedals with oddball requirements. I use (because of my setup on guitar and steel) three One Spot units, but the Voodoo labs units and others do the same thing.
_________________
No chops, but great tone
1930's/40's Rickenbacher/Rickenbacker 6&8 string lap steels
1921 Weissenborn Style 2; Hilo&Schireson hollownecks
Appalachian, Regal & Dobro squarenecks
1959 Fender 400 9+2 B6;1960's Fender 800 3+3+2; 1948 Fender Dual-8 Professional |
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Tim Heidner
From:
Groves, TX
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Posted 20 Dec 2010 3:28 pm
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I had the same problem, this fixed it:
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Bob Sykes
From:
North Carolina
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Posted 20 Dec 2010 8:56 pm
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Tim, try one of the orange ones. They sound better 
Ken's right about the PS. It's a typical ITE 5V (computer) switcher with (most likely) some filter caps to earth ground. We supply these things with a lot of products that are made where I work. We change PS vendors/distributors several times a year. These things are commodities as far as purchasing dept. is concerned. If they have the correct voltage, current, agency markings, price and availibility we'll use them. There's no spec. for audio noise. maybe Peterson shipped different brands over time too, some noisier than others.
I have always had the StroboFlip connected to a tuner-out jack on my volume pedal. Might have to try it in-line. I like experiments.
_________________
Carters Starter, D10 8+7, SD10, Chandler RH-2, Rogue RLS-1
ISO Sustainus Ad Infinitum |
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Tim Heidner
From:
Groves, TX
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Posted 21 Dec 2010 5:41 pm
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| Bob Sykes wrote: |
Tim, try one of the orange ones. They sound better
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surely black would be best?  |
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Tony Kotula
From:
Detroit, Michigan, USA
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Posted 27 Dec 2010 2:59 pm Stroboflip
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I USE THE A/C ON BOTH OF MY TUNERS..NO REAL PROBS..
SOMETIMES AT THE GIG I WILL GET A HUM OUT MY STEEL AMPS...I HAVE MY HILTON PEDAL.. STROBOFLIP.. LEXICON AND A BOSS DD3 all PLUGGED INTO ONE POWER STRIP.
WHEN I DO GET A BUZZ IN MY RIG..I THINK IT'S MORE OF A WIRING PROB IN THE CLUB I WORK AT.UNFORTUNATELY THE NOISE IT INTERMITTENT!!
I UNPLUG THE A/C FROM THE STROBOFLIP. IT GOES AWAY.. OR I WILL REMOVE THE HILTON PEDAL AND USE A GOODRICH. SINCE I CANNOT PINPOINT THE PROB DIRECTLY I CANNOT SAY IT IS JUST THE TUNER. ALTHOUGH I WOULD LIKE A BACK POWER SUPPY FOR MY HILTON PEDAL.
PLUS... CHICKS DIG THE BLUE LIGHT ON THE STROBOFLIP WHEN IT'S PLUGGED INTO A/C. LOL
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left handed Excel Dl0, left handed GFI UNI 12 Ultra, 2 n.ville 400's, DD3,Lexcicon MPX100... |
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