CarlA
768 posts
May 08, 2015
7:04 AM
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Let me preface by saying that I know precious little about amplifiers. Recently, my HG 1210 seems to be much "weaker" in its output and power. It started about 2 weeks ago, and while it used to keep up nicely with a loud band, now I am just drowned-out completely. Not too sure where to start.
Mr rig consists of ultimate 57 with Gregg'd wireless rig, a boss dd-3 delay. Nothing has otherwise changed since 3 weeks prior when the amp had its full set of "balls". Lol
Thanks!
-Carl
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Barley Nectar
797 posts
May 08, 2015
7:43 AM
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How many hours is on it? Try your rig into another amp to eliminate that as a problem. You can also try just the mic and a good cord into your amp, see how that works. IOW, use a process of elimination to verify that it is actually the amp. With that said, tubes are the first thing you want to check. Power tubes are at the top of the list considering your symptoms. Stick a new set in there and give it a blow. If that amp is cathode biased you should be OK on bias. If it is fixed bias, a tech needs to set it up for the new tubes but you can still give it a try, just watch those tubes don't red plate. Don't gig it till you have the bias set. If the power tubes don't help, reinstall the old ones. Swap in new preamp tubes, one at a time. IOW, Pull one old tube then put the new tube in that socket. If no change, reinstall the old tube then repeat on the next tube. One at a time till the amp sounds good. Same with the rectifier tube. Oh ya, swap tubes with the amp turned off but leave the standby switch on during the whole process and keep your fingers off the pins and sockets. If none of this works, take it to a tech. Contact HG for tech references in your area. Good luck...G
PS: DO NOT open that amp up and poke around in there. There is HIGH VOLTAGE in there, even when the amp is unpluged. It WILL kill you!
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Owen Evans
19 posts
May 08, 2015
8:45 AM
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Great advice Barley Nectar. Since Carl admitted that he knows 'precious little about amplifiers', Please be sure to let the tubes cool off before you reach in and grab one. These little buggers will BURN you something' fierce and they stay hot for a while after they've been turned on!
Hope this helps.
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OE Stone
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Goldbrick
986 posts
May 08, 2015
9:05 AM
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Could be a bad power tube or phase inverter tube ( 12ax7wc)
I am guessing you ran a guitar or something straight into the amp to make sure it is not your mic or delay
the phase inverter tube beginning to fail would lower power - get the same brand you have and swap it out ( normally only the power tubes are fixed bias) so that should not be a problem- but if you are unsure call harp gear first
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5F6H
1880 posts
May 08, 2015
10:20 AM
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Do you have a multimeter? If so, clip the meter leads to a speaker's terminals & play some 2 draw bends on a A harp. Try and determine an average reading in the lower AC scale, it'll fly around a bit.
This may help establish whether it is a definite malfunction, or outside influences. It's a safe thing to do, there's no voltage when there's no sound, but don't short the speaker terminals together.
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www.myspace.com/markburness
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CarlA
769 posts
May 08, 2015
10:42 AM
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Ok, a HUGE thanks to all for chiming in and helping out. A lot of good advice and tips to try. I will give them a go this weekend and keep you all posted. Thanks again for taking the time to respond. I really appreciate it :)
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5F6H
1881 posts
May 08, 2015
12:50 PM
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One other thing...easy to say...not so easy to do on the bandstand in the real world...always try to plug your amp into the wall AC socket. Ancillaries can go into a 4 way, if you get too many devices with a big cumulative current draw, it can bottleneck at the 4-way and your tone (particularly, as you are playing longer drawn notes with a more consistent draw on the power supply, compared to guitar) can get a bit 'splatty' & lost.
So, I guess make sure that the loss of power doesn't follow a particular venue/circumstance, is what I'm saying.
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www.myspace.com/markburness
Last Edited by 5F6H on May 09, 2015 1:56 PM
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arnenym
349 posts
May 08, 2015
3:50 PM
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Have you tried another mic cable?
It seems like a silly question but i have had the same problem.
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CarlA
770 posts
May 08, 2015
6:24 PM
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@5f6h
Good point! I never thought about it, but I have a power strip that I have the wireless mic, amp, and pedals plugged into. This in turn is usually plugged into another musicians power strip, which probably contains 3-4 other power strips. I will try plugging in directly into AC and see if that helps.
@arnenym
Believe it or not( I feel like Jack Palance-lol) I have not yet tried to change out the cable. Maybe it's as simple as that. I sure hope so :)
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barbequebob
2908 posts
May 09, 2015
8:24 AM
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If you're gonna use a power strip, check out the number of joules listed because the higher the number, the better because cheapo strips often have less than 1,000 joules and every extra plug sucks power away from the amp and the first place I'd look to buy a better one would either be in an electronics or computer specialist store for one.
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Sincerely,
Barbeque Bob Maglinte
Boston, MA
http://www.barbequebob.com
CD available at http://www.cdbaby.com/cd/bbmaglinte
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CarlA
771 posts
May 09, 2015
8:48 AM
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@barbequebob
Thanks for the tip. I must confess that the power strip I use is an él cheapo harbour freight tools one I got for $1.25 or something. This is also something I will check tonight. Thanks again for the tip:)
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Greg Heumann
2993 posts
May 09, 2015
9:19 AM
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Agree with everything said. I'll add another one. Assuming you were testing with the wireless in place, 1st thing is to unplug the cable from the back of the receiver and plug it straight into your mic. If everything got louder - then it is the wireless - and most likely you bumped the switch on the back from the Line (-20dB) to the mic (-40dB) position. You want it in the Line position!
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***************************************************
/Greg
BlowsMeAway Productions
See my Customer Mics album on Facebook
Bluestate on iTunes
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CarlA
772 posts
May 09, 2015
10:25 AM
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@greg
I did check to make sure it was(and it is) in the "line" (-20 db) setting. Are there any other issues that commonly go wrong with the wireless receiver that can explain these symptoms? Because now that I think about it, the wireless rig was also "acting" up with my double trouble(ie: sound cut in and out sporadically, etc).
It may be something in my pedal chain perhaps?
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Barley Nectar
800 posts
May 09, 2015
11:06 AM
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Pedal Chain! The more stuff between the mic and the amp, the more problems you may have. I feel that some players are so obsessed with pedals and stuff that they neglect the music. I see this alot with guitar players...BN
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dougharps
910 posts
May 09, 2015
11:41 AM
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When trouble shooting it is best to start with the simplest setup and add the pedals and pedal cables back in one at a time. This is best done before you open anything up or swap anything.
If the setup is having problems with just the mic and amp, try switching cables and switching mics. If you have more than one amp input, try each one. Even a dirty pot or switch could cause a reduction in volume.
If you confirm it is the amp having a problem and you have limited experience, I would suggest having a tech check it out and not open it up. If you feel comfortable you could try tube replacements, but it might cost you more than a tech, and it might not be the problem.
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Doug S.
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CarlA
773 posts
May 09, 2015
5:35 PM
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At this point, it seems to be a burnt pre-amp tube AY7? I replaced it and it seems to be working good again. I was pretty sure I replaced them not too long ago, but it may have been the second preamp tube AT7 I guess. Thanks for all the responses, I really appreciate. Oh yeah, I finally maned-up and bought a decent power strip-lol. Thanks again guys:)
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Greg Heumann
2994 posts
May 09, 2015
8:50 PM
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Glad you found it. In the future the very first thing you should do is eliminate everything not essential. Plug the mic straight into the amp. If it got better, then it was one of the things you just took out.
The wireless, aside from that switch or other cockpit error - is very reliable and general works or doesn't - but not half way.
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***************************************************
/Greg
BlowsMeAway Productions
See my Customer Mics album on Facebook
Bluestate on iTunes
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CarlA
774 posts
May 09, 2015
9:05 PM
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@greg
I have been EXTREMELY pleased with the wireless system overall. Your products are top notch and I recommend them whenever I get a chance. Thanks again:)
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Bilzharp
62 posts
May 10, 2015
1:13 PM
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Is Electro Harmonix 12AY7? I had one short internally after just a couple of gigs. Got a couple others that seem to be fine. They are nice and quiet when they work.
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barbequebob
2909 posts
May 11, 2015
10:54 AM
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One huge word of advice one should heed is that whenever you use a power strip of any kind, make absolutely sure that your strip is NEVER plugged into another outlet or strip where the stage lights are plugged into because stage lights can suck up huge amounts of power and will overload just about any power strip in a NY nanosecond and I've unfortunately had an experience with that where the lights overloaded the crap out of everything and everyone's amp on the bandstand completely shut down for several minutes. Luckily my amp as well as my guitar player's amp were tube amps because my bass player had a solid state amp and his amp got fried from the overload and cost him a boatload of money for repairs. Also, many venues may have some seriously old and funky wiring where the ground changes by the minute and can also do damage as well even if you use anything with a grounded 3 prong plug.
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Sincerely,
Barbeque Bob Maglinte
Boston, MA
http://www.barbequebob.com
CD available at http://www.cdbaby.com/cd/bbmaglinte
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