or like a new work orientation video. I immediately get tired.

Educational though

inside is the key word, the tubes aren't really 'inside' the amp

@@ATSaale To a certain extent, you're correct.......the Tubes, although not "IN THE AMP, " what you have to be aware of is the Heat from the Tubes, Oils from your skin can, although rarely, help to speed up the aging of your tubes and WILL DETERIORATE the Glass surrounding the Plates inside your aTubes then, MOST IMPORTANTLY, THE CAPS......OR CAPACITORS LOCATED INSIDE. These Capacitors, can and will hold an ELECTRICAL CHARGE powerful enough to knock you across the street, make your Hair as Curly and Frizzy as mine not to mention, if not given enough time to TOTALLY DISCHARGE, NOT ONLY AFTER YOU TURN THE AMP OFF BUT ALSO UNPLUG FROM THE WALL, there is a very good chance of this Organ/Muscle inside your Chest, called YOUR HEART, WILL ALLOW ENOUGH CURRENT, VOLTAGE OR A COMBINED AMÒUNT TO PASS THROUGH. Thuss making your Heart..........well, you can figure it out......if you live!! MOST Tube Amps are designed and built to not only operate here, in the USA off of 120 Volts, if you read your manual these Amps and their Components like the Power Transformer can withstand the 220 Volts required overseas!!! Thank you for taking the time to read this. It could save your life!!!!

Also: "Wear rubber gloves for extra protection" - continues to not wear rubber gloves

Pat Wilson that had me scratching my head swell

Just enjoy the free tutorial, ingrate.

put socks on your hands to replace tubes or wear cotton gloves. they're not meant to be touched by skin because of the fat fingerprints you'll leave.

Not true. Touch the tubes and save yourself wearing socks on your hands for no real reason other than old misinformation that continues to spread from old pre-internet days when it was hard to ask a real amp tech. Even in this video you see the man changing tubes without covering his hands.

You a Gaylord you think you know I e but you pretend

Shut up I’m smarter than you lmao

This advice comes from the knowledge that oils on skin negatively affect car headlamp bulbs. Tubes are not subject to these issues since the glass surrounding the filament is thicker and also not made of the same type of glass. You’re safe to handle tubes without protection assuming they’re cold. When dicking around INSIDE a tube amp however, different story.

Follow the advice in this video and you'll crash for certain.

sound gets down and up?

Lol

Okay boomer

There are always getting risk electrical shocking IF you don't remove the power cord 🤭. There's a electrical 101 training in KZfaq. I recommend you understanding about electronics before you trying to touch anything that uses power equipment. 🙄

+Perry D I suspect you may have a bad tube or a bad tube connection, or even a bad switch. I suspect that the symptom is there only when you are in tube mode, and not solid-state mode. You might have a malfunctioning rectifier tube, or the tube sockets may need cleaning and/or retensioning, and may be causing a tube to not operate. This model of amp has been produced for twenty years, and it started as a rather less complex design, so I can't be sure which features yours has. But if you can switch power and are running at fifty watts and a rectifier tube isn't operating, you won't have as much headroom as when both rectifier tubes are functioning. Perhaps your amp automatically switches to a low-power mode when you switch it to the clean channel? I honestly know know, but for the purpose of this fix, it's largely irrelevant. You'd have less power & headroom in 100-watt mode as well, but you may not notice unless you're playing at a higher volume setting. Over time, tube socket contacts can develop both corrosion on their contact surfaces and looseness, "losing their grip" on the pins of the tubes and in some cases breaking the connection between the tube pins and the contacts altogether, mimicking a failed tube. Operate the amp in full-power mode using the tube rectifier and try to determine that you are, or are not, hearing the problem. Try it in 50-watt mode, if you have that feature. Give the amp about 15 minutes to warm up, and then try to see if both 5U4 tubes are hot and slightly glowing. There's a quick-and-dirty method that isn't thorough, but it may help. Here's what you can try if one of the tubes looks dead, or even if you suspect it is (you can do this with all the tubes, as a regular yearly or twice-yearly maintenance step): With the amp in tube recto mode, using a clean cloth for burn prevention, grasp the top of the tube and CAREFULLY rock it in a circle, but don't tilt the tube very much, so as to avoid bending (or breaking) a tube pin or a socket contact. You're trying to loosen up any corrosion and/or dirt between the tube pins and the socket contacts, and hopefully restore a secure metal-to-metal connection. You might hear some loud noises when you do this, especially if you indeed have a dirty socket. Try to see if you can hear any difference when you resume playing. If the symptom seems to have vanished, you just may have temporarily cured the problem. If not, go ahead and try a substitute 5U4 tube. If you have a spare pair, replace both tubes. If you only have one spare, try it in both positions and test it each time for the symptom. It's also possible that you do have a bad preamp tube, and you can substitute a new one (or a known good one) in each location, one at a time, and see if that resolves anything. A 12AX7 will work as a TEMPORARY substitute in about every preamp-tube location in the amp. So will a 12AT7, 12AY7, 7025, 5751, ECC81, ECC82, and ECC83. But if you find a bad preamp tube, you must then install the recommended tube for that socket for best performance. This is most critical for the first tube in the signal path, usually either a 7025, a 12AX7 that is suffixed with one or more letters (12AX7A, 12AX7WB, etc.), or an ECC83, followed by the preamp socket located closest to the 6L6 (or EL34) output tubes, which is actually the driver in the output section and is sometimes a 12AT7. You need a high-quality preamp tube in the first position for low noise and lack of microphonics. This is only one basic step in determining if there's a "mechanical" cause for the symptom you've described. If all the connections in the circuit are known to be clean & tight, they can be ruled out as causes. It does no good to replace good tubes with more good tubes, if a bad contact is the problem. If you want me to discuss additional options, please feel free to reply, or just reply to let me know if you already know this stuff, and I'm all washed up or something. Either way, I'll be notified in my email and can then respond. If you want, I can give more details on how a more complete tube socket servicing is done. Finally, for safety's sake, you must be aware that LETHAL VOLTAGES are present at certain places inside the amp, whether it is plugged in or not. Try to work with only one hand, and keep the other away from the amp, or any grounded surface. Stand on a thick rubber mat or rug, and don't wear any metal jewelry or anything that might snag or dangle on any part of the amp. And keep pets and children out of the room. I hope to hear from you.

Perry D, problem is, you need to upgrade to a Triple Rectifier.

Audioman45 why😂 it's like changing a lightbulb

Yeah $128 worth of light bulbs lol

i wouldn't say modelling amps but solid-states are almost like tube amps nowadays.

I have an old Line 6 Flextone lll that is my " GO TO " BACKUP Amp. I'm also preparing to purchase a New Orange Crush Pro CR60C SOLID STATE AMP as my primary. Side by side with my Blackstar and Marshall DSL, there is VERY LITTLE difference in tone when it comes to comparing Solid State Tone to Tube Tone....the Amps sound totally different as they are all DEFINITLY DIFFERENT AMPS AND CIRCUITRY!!! Tone wise though, plenty of Low End, Great Mids and the Clean Channel is incredibly, sparkling CLEAN!!!.....Not to mention, having only 1-12 inch Speaker, compared to a 212 Combo and a Half Stack, my Spine is loving me for it!!! My Line 6 Flextone lll Amp is now over 15 years old and the ONLY ISSUE I've ever had, actually had nothing to do with the Amp. The FBV Shortboard was the problem. The Display Screen went bad and when that happens, it SCRAMBLES every saved Preset you've created, hence losing ALL of your sounds!! Unfortunatly, they no longer make replacement parts for the ORIGINAL Shortboard and the newer Mark ll and Mark lll Shortboards WILL NOT WORK WITH THE FLEXTONE!!! I've spoken with Line 6 about this issue and they have NO PLANS WHAT SO EVER to resolve this by re-issueing the Screen.......BUMMER!!!! This, of course, has sent the prices of USED ORIGINAL FBV Shortboards sky high. In the over 15 years I've owned this amp, the Screen has only failed me twice....twice too many times, as I had to spend a fortune to purchase on online, 1 from OVERSEAS, WAIT FOR CUSTOMS TO DO THEIR JOB, PAY THE IMPORT DUTIES NOT TO MENTION THE INTERNATIONAL SHIPPING ON AN EXTREMELY HEAVY PACKAGE!!!! The Shortboard is light but by the time you have to OVERPACK for shipping to keep it safe, then go throught all the Import stuff, It cost me MORE than what they cost BRAND NEW.....nearly $275. If you can find one here in the states, HOPEFULLY the seller has a video or picture showing the unit working. Otherwise, you'll be paying about $100 or more for a DOA product.....that is unless you get it off of eBay where eBay WILL REFUND YOUR MONEY if the Seller shows it as a WORKING UNIT on their listing. A Seller can list the item " AS IS, NO REFUNDS, " but if shown working or they state in their listing that the unit ....Screen works as it's supposed too, the Seller has ZERO recourse and eBay will AUTOMATICALLY WITHDRAW FUNDS FROM THEIR ACCOUNT AND REFUND YOU. Lucky for the Buyer; eBay saves ALL LISTINGS, PHOTO'S as well as COMMUNICATIONS between Buyer and Seller just for this issue and others like it for quite a while or until the issue has been resolved to both parties satisfaction!!!! OK, enough about eBay. The PLUS SIDE, if and when you DO find a WORKING DISPLAY SCREEN, the moment you replace the Screen and test your Amp befor putting the Shortboard back together, ALL OF YOUR SAVED PROGRAMS WILL RETURN!!!! That's been my experience....TWICE!!!! The only things I had to re program were the Titles of my Presets but all of my Presets I created returned to their ORIGINAL way I set them up....so KUDOS to Line 6 for, at least, designing this Amp in a way to store your Presets should the Short or Longboard crap out on you!!!

You are correct...it is like changing Lightbulbs......VERY EXPENSIVE LIGHTBULBS...LOL... Lucky, Preamp Tubes are not that expensive, $10-$25 each, depending on the brand. It's the Power Amp Tubes where the Wallet starts taking a hit. Power Amp Tubes MUST be sold in MATCHED SETS, wheather it's a Matched Pair or Quads. You cannot replace just 1 Power Amp Tube at a time unless you wish to start replacing your Tubes every Month or so. Very few Amps are " Self Biasing, " even if yours is a Self Biasing Amp, I would NEVER TRUST one that states that. You absolutely HAVE to have your Power Tubes Biased EVERYTIME they are replaced or again, be prepared to start replacing your Tubes on a regular basis unless you are replacing the Power Amp Tube with THE EXACT BRAND, MODEL AND POWER RATING. That is the 1 and only time you don't have to have your Amp Biased. Unless you just got a bad Tube, even after replacing the 1 Power Amp Tube, personally, I would still pay the price to have my Amp checked out to make sure ther's not something else going wrong in that 1 V Section....such as a bad Socket or a Capacitor going bad.....with Tube amps, you just never know. Tha's why they are so expensive compared to Solid State. There is so much more that goes in to a Tube Amp than a Solid State which is why Tube Amps cost so much more to repair as well as make. I'm sure you know about Biasing, for those who may not, you have to make sure that the Current being drawn across the Power Amp Section is within Specifications or 1 or more Tubes will start working harder to draw the correct Current all the way across your Curcuit Board. This makes your Tubes work at more than double their intended consumption which starts a Chain Reaction causing the other Tubes to start getting weak or to fail all together. This will start to COOK EVERY TUBE IN YOUR AMP!!! I own Tube Amps with my Blackstar and Marshall DSL and it's not cheap to replace the Lightbulbs and have them Biased!! Lucky, Preamp Tubes DON'T HAVE TO BE BIASED.....they are truly like replacing a little more expensive LED or Compact Flourescent Lightbulb!!!!...LOL.... Please understand, I'm in NO WAY trying to BASH you or MAKE FUN of you in any way. Your comment just gave me the platform to educate those who don't know the process of replacing Tubes and why Tubes have to be done a certain way and Biased. If you feel, in any way, I'm trying to be mean or rude about your comment, PLEASE DON'T.....THIS IS CERTAINLY NOT MY INTENTION!! Take care and Play On!!!

Test the tubes

Hi, Jon. Great question! It does sound like you need a tube change. I would compare it to an oil change on a car - even if you don't drive the car very often, it is a good idea to get the oil changed once or twice a year. If you have any other questions feel free to reach out. Thanks! Jason Filloramo, Sweetwater Sales Engineer, (800) 222-4700 ext. 1281, Jason_Filloramo@sweetwater.com

Remove the power tubes and if the fuse doesn't blow when it's switched out of 'standby' it's most likely a failed power tube. It could also be lack of negative bias, so that would need to checked before installing new tubes.

@Luke Robinett yep, dazed and confused by the fact that a 80's fender amp I had just bought had problems did cloud my judgement. So that was the case and has been fixed now. Thanks for the statement of the obvious to which I was oblivious back then !

Hello, Norman! That doesn't sound normal at all! The Standby switch should mute the speaker level output of your amp (it may not mute other things like the silent recording output). The good news is, if you bought your TubeMeister from us here at Sweetwater, you're entitled to free Technical Support from our dedicated team of in-house technicians. Give me a call if you'd like as, I'd be happy to help any way I can. Thanks for the question! Brandt Miller, Sweetwater Sales Engineer, (800) 222-4700 ext. 1628, brandt_miller@sweetwater.com

jjmora05 Hi, please call us toll free, 800-222-4700 and a Sales Engineer can help you out.

SweetwaterSound Hi, I recently bought a Fender Greta and it has a problem. When it's been on for a little while the volume drops or sometimes just fluctuates. Does this sound like a valve issue please?

We apologize for the late reply! If you haven't already, give us a call at (800) 222-4700. One of our techs can check it out for you!

This happens to every amp

@@TheMausymaus , wrong.

Have you solved your problem?

No

Tube amps suck and have endless problems.

+Heavy Metal For Life Your amp is well worth repairing, and can be made to sound as good as new. Rectifier tubes need not be a matched set, and one variety of 5U4 may glow more brightly than another. Still, it may be that you have one bad tube out the pair. Shut it down, let the tubes cool for at least five minutes, swap the positions of the two 5U4's, and power it up again. If the same tube appears cool when it's in the other socket, it's a good bet that you have the bad tube identified. Pull the suspect tube out entirely, and see if the amp behaves differently, or if it sounds pretty much the same. If nothing changes when you remove it, you have more evidence of a bad tube. Doing this will not harm the amp, but use a towel or something to avoid burns. If the cool tube is always the one in the left-hand socket, or always the right-hand socket, chances are that either the socket contacts are holding the tube pins too loosely, or are coated with dirt or a film, and are preventing the tube pins from making electrical contact. Or, a wire soldered to the socket may have overheated and needs to be resoldered to the socket. As far as the "sandy" sound, there are a few typical causes. For one, the 100kOhm (sometimes 82kOhm) resistors soldered to the plates and grids of the preamp tubes may have met their doom by being stored in a damp environment, and they are one of the chief causes of a hissing or sometimes a popping noise. If you know what you are doing, you can simply replace ALL the 100k and/or 82k resistors in the amp, to be certain. Another cause, especially for amps that haven't been used much, is the same damp environment allowing moisture to get into the transformer windings. Inspect VERY CAUTIOUSLY for any signs of rust or paint peeling on the surface of the transformers, but DO NOT attempt to clean it off. Note it as a possible sign of a decayed transformer. Was the amp stored in a basement, or any other damp area? Sometimes, this can be largely remedied by leaving the amp turned on continuously for several days, allowing most of the moisture to escape from the confines of the (heated) transformer housing, even if there's no obvious sign of moisture damage on the surfaces. Another thing you can do, provided you have a known good spare preamp tube, is to try the "tube substitution method". Be very careful if you do this, and don't ever put BOTH hands in an amp, powered up or otherwise. Use one hand only, as a critical safety rule, and keep your other hand from touching the amp, or anything else that may be grounded. Swap your good tube with each of the tubes, one at a time, and listen for any improvement each step of the way. Test all of the preamp tubes this way, and pay close attention for any improvement in the noise levels each time. Don't strike the tubes very hard, but use your finger to gently tap each preamp tube, while the amp is powered up & in full-on mode. You may need to pull the chassis from the cabinet to do this. If you don't hear a thing, don't tap harder, turn the amp up instead. If you still don't hear much of anything, that's good! The one that is the loudest through the speaker when you do this will be the most critical tube to replace. It's the first tube that your guitar signal encounters, and so any noise coming from that tube will be amplified more than the noise from any of the other tubes. It's almost always a 12AX7 variety, but a high-quality version, such as a 12AX7A, 12AX7B, 12AX7WB, etc, or a 7025 (military-grade 12AX7). These have been tested & chosen for their low noise and low microphonics, among other things. Finally, a normal tube gives off an emission of random noise, called "blow", which usually subsides after fifteen minutes of being turned on, but it may take even longer. It sounds a bit like the surf! It seems to be worse if the amp has been sitting a long time, for some reason. This can contribute to the noise you hear, even if it isn't the sole cause. The thing to keep in mind is that you can do all of these procedures with no test equipment and with little or no out-of-pocket expenses, except for a preamp tube, if you don't have one, some relatively inexpensive 1/2-watt resistors, and you may also be springing for a set of rectifier tubes in the end. Just keep that amp warm and dry!

+randolph patterson hii have a amp and 1 tranformer is have some like orange paint like a small eye drop--anyidea what might can be ?

Did you get your amp repaired? I have a Monoprice tube amp as well and found this video looking for a way to diagnose my problem. I tried the effects loop for the first time last week. After about 15 minutes of playing, the main fuse blew. Now the fuse blows immediately every time the amp is turned on with no guitar or effects pedal connected to any input. It does the same with all tubes removed, so I don't think any of the tubes are the problem. I'm guessing I'll have to track down a local amp repair shop.

@@poit57 TN, I have always used solid state amps and this Mono was my first toe in the tube amp pool. I rarely used the effects loop on the SS so I wasn't sure about using it. I've read that the Mono is the same wiring as the Laney Cub. I upgraded the tubes and swapped them out with the old ones when they arrived. Have not had any problems since I put them in. I'm buying a Fender 68 custom twin in a couple months so I'm truly upgrading in the tube amps dept. Just bought a Peter Frampton LP copy so I'm using that through the Mono and it sounds great. Am also using the loop and have zero problems with the amp.

Dean ok so should I buy another power matched pair and replace the faulty tubes? Thanks for the help man

i have the same issue. xlean channel is fine but dirty channel needs to be on full. with gain all the way up to be heard at all. changed the tunes but no luck still ;(

Each pre amp tewb has two triode sections eg section A and section B.. if the distortion channel and clean channel share the tewb , like , clean on B, distortion is usually A and B ,then 1 side of the tewb is faulty..change the tewb, (chuckle ) . If that dosnt fix it, you have a fault in the signal path , eg bad solder, (sodder) joint or faulty component..

steeveejay My twin reverb makes a popping noise every time i turn it off of standby. But mine still works fine.

EpicDailyShow Could be a few things, If it only started popping like, recent it could be a sign of a bad switch contact . soon as you flick tha switch , theres like 520 volts blasts its way to the choke and evens out at 460 volts.. if the switch has any corrosion from arcing it may be the cause.. If you replace the switch , solder a 20 or 30 uF cap across the switch terminals and it will last way longer .. Make sure its plastic and rated for 630 volts.. The cap changes the rate of charge so reduces arcing.....Hope that helps..

+ecko911 Sometimes, the footswitch itself is the problem, and a wire often seems to break right at the spot where the footswitch cord goes into the footswitch housing, directly underneath the grommet/strain relief. If this is the case, your amp should be okay when the footswitch is disconnected, but the symptom appears when the footswitch is connected to the amp. If this sounds like the way your amp is behaving, you'll need to take the footswitch apart and inspect the wiring right where the cable comes into the housing, and perhaps check the solder connections on the other end, where the cable plugs into the amp. The simple act of plugging in the footswitch while the amp was in standby should never, ever cause a failure or a malfunction all by itself. One caveat: this generally applies to mechanical footswitches, and everything I've said may go out the window if the switching is accomplished by digital means. Still, it won't hurt to look for a broken wire, a failed solder connection, or a worn-out switch assembly.

Hello, Chris! If it doesn't have as much grit as it used to, but your tubes have been changed recently, it could be that the amp was biased cold. Also, you might just want to check the bias if you play it a lot, but it doesn't yet require new tubes. A simple adjustment could be all you need if the manual for your specific amp has re-biasing instructions. If you purchased the amp from Sweetwater, feel free to give our Tech Support team a call, or reach out to your Sales Engineer. Or, take your amp in to a local guitar amp tech. I don't recommend poking around inside your tube amp if you don't have much experience, because they do carry a LOT of voltage. Thanks for the interest! Kevin Spunde, Sweetwater Sales Engineer, (800) 222-4700 ext. 1732

yup. weird.

+1952TeleDude Sounds like a tube is microphonic on a note disagreeable with the amp. That tube probably happens to resonate somewhere between E and Eb. Change the tubes to something not microphonic, or not microphonic in a range that effects the amp. I think nearly all of them are microphonic to some degree at some frequencies, and only when in certain amps, due to the amp itself resonating better at certain frequencies. Its really just a case of bad luck i think man. I had issues once with an amp playing a low E, which did turn out to be microphonics, but'fluttering' is an interesting description. Mine was better described as scratchy. It helped by not pushing the amp against the wall.

a power amp running a signal that doesn't have a pre amp will be very weak. there are 3 levels of electirc signal: Insturment level (weakest and what a guitar puts out), mic level (mid level and what mics put out), and line level (strongest and what cd players/keyboards/cell phones etc put out). power amps are built to work from a line level input only. if you send them an instrument level signal, they won't do much with it. plugging into the send bypasses the preamp, sending your instrument level signal directly to the power amp. hence weak.