on the distorted channels of my brand new H&K Switchblade 100w amp i pick up some AM radio that plays zideco and mexican music. how can i stop this? i also get it on my line 6 spider whenever i use my wah pedal. note that the cabinet i just bought... no refunds no returns... was built some time in the late 80's early 90s by mesa boogie. however, i tested it out with a different head and there was no funky radio. i am thinking A the ground in my apartment is not good... or B the head is not good. i bought it "blemished" and i rly hope this isn't the blemish how frustrating!
My Laney combo picks up CRAZY radio and BUZZY RADIO here at the house. At church, it's quiet as, well, a church mouse. It's the house, dog. I hate my house. I want to know how to kill this, too, other than telling my landlord that when he built the place years back he did a crappy job on the electrical work.
i'm thinking power conditioner maybe? as i stated, the line 6 doesn't have this problem unless i get the wah going i'm trying all the different outlets each time i play, which is every couple of hours the amp is ok... will rate it later. first impression... nice lead, nice clean, OK but lacking rhythm, useless (cheap sounding) FX. i may be sending it back and buying a single rectifier in its stead
the master is pretty low. the channel volumes are pretty much all the way and the gain is at about 2 o clock.
Before you make a decision about the sound you don't like, give a shot at turning the master up a bit, just to see. One thing that a master volume can't do (that most good attenuators can) is make frequency compensation. Our hears hear different frequencies, well, differently at different volumes. But ultimately, if you're unsatisfied, ditch that thang and check out something else.
i tried multiple half stacks... good ones and shitty ones, and this is the only one that is getting radio.
No need to "learn to live with it." I'm sure there's a solution. I'd like to look into the power conditioners more, because the Furmans claim to eliminate radio interference as well.
well, its the lines in my building that are at fault! we practiced at the drummer's place today... no problems whatsoever growing to love the amp as well... sounds pretty good at full vol.
Don't want to start a shitstorm, but this is one of the benefits of digital processing. Haven't had that problem ever since I got my PODxt. rumborak
If you're really daring, you could put a coat of copper shielding paint on the interior of the case...
These threads discuss the issue, and some potential solutions: http://www.talkbass.com/forum/showthread.php?t=303723 http://www.talkbass.com/forum/showthread.php?t=299256&highlight=radio http://www.talkbass.com/forum/showthread.php?t=167512&highlight=radio This is a link in the third thread, for an item that eliminates the problem: http://computer.howstuffworks.com/f...http://www.antennex.com/shack/Dec99/beads.htm
Not necessarily. The drummer's place may not expose you to the radio signal you were picking up at your place. If your building has grounded outlets (most do and should), you should be able to get rid of (or at least minimize) the noise rather easily. If it doesn't, you'll never get rid of it unless the radio signal strength diminishes. First, check your outlets for a true ground and try changing the ground lift switch to a different setting (assuming the amp has one). Second, buy a short cable of good quality and try it. Your cable acts as an antenna in these situations. A shorter cable will often lower the capability of stray reception. Without a grounded outlet, this may be your only answer. Most power conditioners require a proper ground to do anything significant as they will filter any high frequencies (RF) to ground. Without one, they can't do much as a grounded neutral line is unreliable for this aspect of the conditioner.
fuck. my drummer does live in the boonies why am i such a noob?! hmmm this is annoying. the amp might have to go back i dunno how to check for true ground. but appliances in the US run at 120v, right?
Oh, yes, it absolutely can be. There is no reason that a properly designed and built audio amplifier should double as a radio. It's not to say that its RF shielding and aforementioned filter circuitry hasn't been compromised by out of date building wiring. But, if the wiring is intact, there is a problem with either the amplifier, guitar, or cable. Much of the time, a faulty shield connection in the instrument cable or instrument is to blame. However, it can just as easily be internal to the amplifier.
I've had solid state amps that captured radio, too (actually, just about every one I've had captured radio). This problem isn't unique to valve amps.
The easiest way is with an outlet tester. You can pick one up for about $10 at your local Home Depot. It can also be done with a multimeter or a test light. I would opt for the outlet tester for those not schooled in basic electrical.
and that tests the ground? i am close to the management and owners of this building, they have the schemes, etc. i can get an engineer to chceck stuff out, etc. so should i just ask them if the building has a true ground?
I was actually more talking about the first part of the signal chain, ie foot pedals and stomp boxes. Didn't DR_SAAD say that it picks up the radio when he switches on the wah? I would say it's a problem of the wah then, not necessarily of the amp. There's many ways of picking up radio down the signal chain, not just within the amp. The guitar pickups can do it, badly shielded stomp boxes etc. etc. rumborak
to clarify, the wah picks up radio. i've only tried it with the line 6 spider, but it picked up radio. the spider does not pick up radio without the wah. i haven't tried the wah with the h&k. i get radio on the h&k without the wah. i've tried my axe out with several amps and got no radio.
I would suggest you focus your attention on the wah then. It might be just badly shielded. My Crybaby wah is definitely a pretty cheap piece of equipment, having looked inside it at some point. rumborak
The building most certainly has one. The problem is, the extension wiring might not. If the building was built before 1975, there's a chance that it doesn't. Many amplifiers utilize earth ground (connected to the amplifier chassis) to internally shield sensitive circuits from electromagnetic interference. Another (and more important) reason to make sure your ground is solid is the fact that you could get a lethal shock from the amplifier if anything high tension became shorted to the chassis. If you know the owner, have them check it.
The building most certainly has one. The problem is, the extension wiring might not. If the building was built before 1975, there's a chance that it doesn't. Many amplifiers utilize earth ground (connected to the amplifier chassis) to internally shield sensitive circuits from electromagnetic interference. Another (and more important) reason to make sure your ground is solid is the fact that you could get a lethal shock from the amplifier if anything high tension became shorted to the chassis. If you know the owner, have them check it. Inside or outside of your apartment building?
In general, on of the first orders of action in a new rehearsal space should be to see whether all sockets are properly grounded. People have died from electric shocks they got from ungrounded microphones. rumborak
that is insane they never mention this in music/production classes, at stores, etc. rumbo, the wah is only anectdotal. if the amp gets radio without the wah plugged in then my problem is whether or not my switchblade is defective compared to the rest of the switchblade amps out there. as for trying it with other amps, it was outside my apartment, but in well populated parts of houston. assuming my apartment doesn't have a true ground, what do you think i should do?
I'm certainly betting on an absent ground or faulty amp at this point (there is a reason it's a "scratch n' dent" model, I'm sure.) The electrical hazard isn't imminent, but it is very possible if the conditions are right. Your body must complete a circuit in order to get a shock, so it's pretty unlikely that it would happen in your apartment. I know this isn't comforting, but it's true. You would actually have to be grounded or in contact with a neutral conductor in order for it to happen. If you have someone over to jam, there is a possible chance of "floating potentials" between your amps with no ground present. So, you might get a zap if you touched both guitars at once on a metal part. This HAS happened to me before in this very situation. The cause was a faulty ground connection inside of one of my amps. Consequently, I always bring a multimeter wth me everywhere I go to play. If you don't have a ground, any cold water pipe can usually serve as one provided that it is made of copper. The pipes are all soundly connected by solder and the main pipe comes from underground. If your building is older, your plumbing is probably copper. You could temporarily run a piece of copper wire from your outlet's ground lug to the water pipe (there are special clamps to do this). It isn't the best solution, but it is better than nothing. I would definitely get someone who is in the know to do this for you. It can be dangerous if you don't know what you're doing.
thanks for the elaboration. i did notice that when the guitar cable is not plugged in but the amp is on and not in standby, there is no radio. the lead channel does have hiss even with nothing plugged in, though. is that normal? i didn't find that i could eliminate the hum by touching any of the metal parts. i've dealt with ungrounded equipment on a couple of occasions and found that touching any metal with my finger would eliminate the hum as long as contact was being made. so i would suspect that the hum is not ground related. but it could be. argh, this is confusing! anyway, tomorrow i will pick up, at the very minimum, a good shielded instrument cable (most likely monster) and if possible an outlet tester as well. i'll let you know how it goes!
Sounds to me like it's just the cable acting as an antenna. I reckon a new cable will solve your problem.
ok good news. the seller has agreed to give me either a refund or a brand new replacement at a discount or a replacement with a different product. they will pay shipping for everything. good people! zounds... now i have many options to weigh. an important question follows... if the new cable fixes the problems does it mean the amp is not defective at all? or is it defective with a defect that can be dealt with in one way or another? i'd rather pay a little extra to get an amp that any cable works with, etc. but if its the case that the problem is 100% related to my instr. cables and nothing to do with the amp there's not reason to return it. you know what i'm saying? if my switchblade is the same as any other switchblade and i just need a cable that's cool. if all switchblades have this problem and the cable doesn't help its a problem. if mine is in worse condition than others then it is a problem as well either way, more news when i have the cable tonight!
Yeah, there's just no easy answer. You really have to replace every single part in the equipment chain to see which is the offender. rumborak
Not really, the amp should soak up RF caught by a cable, but some cables collect more interference than others (keep the cables short!). H&K amps don't seem to have a shunt cap in the input jack, at least some models I found schematics for but it's an easy mod to do, there are even parts available for that very purpose of shunting the cable sleeve. And for ground, even if your wall outlets aren't grounded, you can take an extension from bathroom or kitchen outlets, they always have proper grounding even in old houses.
ok... got 2 monster instrument cables. i asked for the best, that's what they gave me. couldn't find an outlet tester (sold out at wal mart). i've tried both cables. same exact problem. with both guitars! the level of the radio is pretty low, and its worst on the lead channel. as i've stated, the radio noise is not there when there is no cable plugged in. so it seems like there's nothing else i can do except try to plug it in in the kitchen or bathroom and see how that works out. i feel like its the definitely amp at this point. many people here seem to just live with the problem. should i? is the amp having this problem because its defective, or will pretty much any amp i use in this apartment have the same problem? these are the questions i'm dying to know answers to so i can make my mind up
That's a damn good question. And, I know the answer: "Because that's the way we've always done it before." A true balanced input signal just makes infinitely more sense for this stuff.
for the record, i've tested the the outlet and the tester says that it is wired correctly, ie. there IS a ground. it has a disclaimer though, that it does not determine the quality of the ground
The fact that a ground is present and the fact that your other amp does not pickup the signal unless it has a questionable stomp box in the signal path are probably enough to prove that the head has issues. I'd return it or at least try another head under the same circumstances. It sounds like the head has a problem, though.
i got a furman pl-8 series ii power conditioner today... the furman...eet daz nathing! that's right... the power conditioner didn't help. now one thing i just remembered... when i used my vox pedal with the line 6 in another place, no radio. when i use it here... radio! furthermore, at the drummers house i had no problems with the H&K. mark is pretty sure its the amp... but brian says he puts up with this all the time and doesn't fault his amp. plus my experiences outside of here are good. argh! i'm confuzzled! i think the best thing IS to try to get a tube head out here and test it out... see what happens. i'm tempted to buy a new single rectifier to test side by side. i'll have the option to return either for a full refund - i keep whatever i like best. i'm aware its 50w vs. 100w but who really cares? there are two things i DO NOT WANT. a) not return the head and it turns out to be defective. b) return the head when it ISN"T defective and pay extra to get a slighly newer one that'll have the same problem. thing is i have a busy weekend and don't know how soon i can do this... and what GC is gonna have on hand for untouched single recs. no way i'm getting the floor model!
The reason I don't fault my amp is because it's happened with every amp that I've owned in the two houses I've lived in in the past several years, both of which were built by the same guy, my landlord. This doesn't mean that it can't be the amp's fault, but I'm always suspicious of the potential for a crappy job done on wiring the house, because of my experience. I could be wrong, but hey.
One of the "arguments" could have been "Well, the connector is too big, it would be ugly". But, there are also "mini-XLR" connectors (http://www.bhphotovideo.com/bnh/controller/home?A=details&Q=&is=REG&O=productlist&sku=365931) Damn, those look really attractive. I wonder how much it would take to refit the guitar and the amp to support those. rumborak
prolink, i think. just a six footer... and it was $20! better be good. but they claimed they didn't have anything better.
Yeah... the $20 prolinks aren't any better than the $20 Fenders or the $20 planet waves... http://www.monstercable.com/pro_audio/productPagePro.asp?pin=2324&LastPage=Instument Cables <---There's the good stuff. I have one of them, and it really does sound much better than other cables. I just wish I could afford to replace every cable in my rig with them.
