Tube amp hum no sound. 2023 Repair 0 Comments.
Tube amp hum no sound. I … BAD TUBE INDICATOR.
Tube amp hum no sound I fired it up for the first time today, and it makes a loud hum, through the speaker, level of the hum is adjustable with the volume knob. Joined Feb Hoffman Amplifiers Tube Amp Forum, Getting the hum out of a 65 Vibro Champ. But it is there. However, the sections on power problems, hiss, and hum should work pretty well for any tube amplifier. that amp never made any sounds for me, sorry man . After about 30 seconds the amp shut off. PrimaLuna engineers wanted to make owning a tube amp so simple you would have no excuse not to have your tube dreams come true. I don't see the point, as from RG's advice, if both volume knobs increase the hum volume, then the hum is coming in before the gain stage. Here’s how to address them: Step 1: Tube inspection – Test each tube one by one by gently tapping them while the amp is on. I replaced the tube with another and the hum went away - but only for another few hours of play time (much longer, though, this time). Miles Prower said: The hum is more or less consistent, no matter what I do, I have taken out all the preamp tubes, same result. 5 If this won’t solve the problem, you should perform a diagnosis on your tube amp or just call for professional help. Thanks for any help or suggestions you can provide. Old power caps and aging output transformers are most likely the cause of excessive hum. When the power tube fails and red-plates, it will loose most of its audible character as it will no longer respond to any AC signal on the control grid. I recorded it. I BAD TUBE INDICATOR. When I fire it up I get no sound from my guitar. If a tube fails, Adaptive AutoBias will instantly put the amplifier into protection mode so no parts can get damaged. So I bought an amp online, it all checked out on paper and it has been recently serviced. ill report back! also, when i pull the preamp tubes the amp goes totally silent. Check or replace all the power supply To identify the damaged one, tap all the tubes with the help of a pencil and hear the sound. Ground input to CF tube with . 3VAC heater supply. That’s a physical limitation of this old technology. The power transformer radiates a magnetic field, at 60 Hz. 50 and 100w Amos, there gonna be some hum. After taking the cable out of the connector some funny irregular buzz sound comes from the speakers for Both parameters are important — amp is idling, and the tube is seeing the amp’s actual operating voltages, which are often in the 400v+ range. This is with nothing connected to the amp for It made a sweeping oscillating sound that was very loud. Of course since the power is off on the preamp and no signal feeding to the amp. The hum is coming from the speaker; if i disconnect it, the hum goes away. It has a low level hum that sounds like 120 hz AC leakage. However, I have been "tube curious" for decades and when I came across a Monoprice Pure Tube integrated amp (model 27222) for $220 on Craigslist I couldn't resist. 2) The flux from the PT is coupling into the OT in Part 2. Hum mostly goes away. i'll put it back in and measure and see what that does. I wonder if it is something to do with the grounding? it's probably just me being fussy The turns ratio on the output transformer is maybe 20:1 so if you have a few hundred mV of hum on the 360-400 V B+, you will have tens of mV of hum on the amp output. Upon arrival, I plugged in the 50 watt tube combo only to hear a loud feedback like hum, even with the volume all of the way down. I don't know this old amp, Fender had balance adjustment in their Black Face and Silver Face amps. If I plug a guitar in, NO sound comes out of the speakers If your guitar amp turns on but you get no sound then this guide will take you through some easy fixes to quickly get your amp working again While unwanted noise can be hugely frustrating, it doesn’t always mean your amp is no longer working. Hello everybody, I have to state that I am not an expert: my first goal is to understand more. A red LED will light up in front of the tube that needs replacing. One special case is tubes. Members; 11. I just finished a build on a Fender MusicMaster Bass amp. Turn it up to about 3 and hit a note (particularly a low note) or a chord hard, and the amp makes the most God-awful distortion right on the beginning of the note. If I think it's going to be difficult (which I suspect it might be), I will search for a local tech. I remember that I had something similar happening after using it with headphones one evening. I bought a later model Peavey Classic 30 amp. I bought this amp off somebody on the assumption it needs a tube change, though that wasn't the case. Is the bias good at -24? I'm not sure now. open For context, this is my first tube amp and I’ve been using amps and pedals for about 4 years. If there's a master volume that would need to be turned up. If you want a sound with greater clarity, it might be worth switching to the best solid state amp you can afford instead. Dave Owens. I've heard from people that tube amps just naturally hiss. Failing that, I would check the power supply capacitors and all sections of the power supply. AND - it is my experience that you can make a hum free, noise-minimized tube amp with Merlin's ground scheme (bus bar, fig 15-10) and AC heaters! Last edited: Feb 10, 2023. It doesn’t stop when I pull the other two preamp Hey, I have a Peavey 112 Bandit solo teal stripe scheffield. This page has proven useful to quite a number of people by the reports I've received. Just hum, noise 3. It's single-ended, so no center tap. I swapped tubes, interconnects, rerouted wiring in the SP14 and other stuff. It dopes however hum quite a bit. My speakers are fine, the attenuator is fine, cables are fine, but the amp is damaged. The amp passes signal but makes strange, non-musical sounds. Rockola 1426 jukebox “O” amp. Tube-related issues can significantly impact your amp’s performance. Posted September 19, 2010. i would think that would make the voltage on pin 3 higher even, not lower. I immediately shut it off. No sound at all with the power tube out. (alternating current), a 50 or 60 cycle voltage taken from a winding off of the power-supply transformer. The amp has developed a low level hum through the speakers which is not dependent on the volume control or input selector. If the hum is internal you should have the hum with nothing plugged into the amp, and it usually makes no difference is the channel volume is turned up or not. The humming comes through the speaker and the rattle are just the tubes itself. Tubes aren't the best. Find out the reason of issue and proper way to fix them. To better assist it really helps if you have high quality pics of the amp, so we can look around for potential sources of the problem. When i switch on and after a while tube comes alive and then gets the sound in headphones. Took the old ones and put them in another amp, no problems. At the end of the day, the effort of pushing and amplifying a current means some level of buzz is standard in any amplifier. Sometimes biasing wierdness or one tube working much harder than the other at idle (sometimes can cause hum, I think) 4. Farther away you are from other electronics the better. Output transistors may fail but are not usually the cause of low output. I’m not an expert in this and got help on Reddit from a very kind and patient person. Hum also disapears when I pull V2. Also, all tubes are all seated properly. It took a while but I got a fix! This I can hear the hum from about half a meter away. To cut cost on this little student amp Valve amplifiers, also known as tube amps, are revered for their warm and rich sound, but they can occasionally present a frustrating problem: hum. Pulling V1 and V2 has no effect however, pulling the 6AN8A (V3) the hum disappears. When I plug it in, there is just a hum. does a pretty good job of being a Hi-fi amp with a distortion option using the input gain. One of the issues the amp has is a loud crackle/rumble sound that occurs 30 seconds after the amp is turned on from cold, and lasts about 10 seconds and then does not re-occur until the next time the amp is turned on. Sounds like it is somewhere between v2 and input. Pulled Input tube for Top Boost channel and leave CF tube in, hum is there. One of the functions of capacitors in tube audio circuits is as ac coupling or dc blocking between stages. And it's all away from computers. com/PsionicAudio, or email us at info@psionicaudio. It’s a 2 el84, 3 12ax7’, treble bass and master volume, amp. The incoming power to the amp (from the moment the wiring enters the chassis up until it enters the power transformer) can generate hum. . I first turned it on and immediately heard a hum. What about metal resistors here for v2? There is no hum or buzz or any sound at all with v3 or v4 removed . Instead I get a prominent 60 cycle hum. How to Convert a Gibson GA-5 to a Fender 5F1. Hopefully, with some minor If you switch off the power amp does hum disappear immediately, or take a few seconds to go? My guess is that the power amp is injecting some hum current down the You might have noticed an amp hum with no input, and you’ve no clue what is causing this. No footswitch connected. the hum can be REALLY bad if both circuits are hooked to different grounds. The amp was recapped but had a hum problem. In this video I show how I repaired a Fender Frontman 65 Reverb with hum. Often, the venue is running refrigerators or other "noisy" devices on the same circuit you plugged into. I see 60Hz hum at the speaker. 6A3sUMMER. An amp tech says that it is a dodgy output tube and so I have ordered a matching set. So you’ve just spent decent dollars on an endgame tube amp. One is heater-induced hum from the 6. If your Guitar Tube Amp Hum With Increases Volume, You can effective way to fix it. These amps have been in service over 50 years, therefore they will develop bad co Does anyone have integrated tube amp that encounters with hum or bug sound? At 1/3 volume, it's great but when I turn the volume to 1/2, I can hear hum on both speakers. It was a cheap/quick easy fix. e no hum and lights up, the rectifier (6B6G) and amp tube (6v6G) are working well) but all I receive is static connecting a long antenna into the ant input doesn't seem to make any difference and I can’t hear any tapping though the speaker if I was to tap the ant input. I can load the STL suite through Reaper but I have no sound. I am going to attach pics for the group to review. The R100 is an 845 tube amp with 30 WPC and the LM 508IA is a 805 tube amp with 45 WPC. If you plug into one circuit and the PA is in another. The low decay settings make the sound more robotic, whereas the high decay makes the sound softer. The 220K V4 grid leak resistor goes to ground at the footswitch and the . It stops when I pull the phase inverter. I've had microphonic preamp tunes squeal like crazy and make an amp unplayable at any volume and I've had power amp tunes go wacky the same way so it's possible it's a dicky tube. Both the gain and the master volume knobs on the amp increase the hum volume. No sound. 4) the tube amp sounds better and cleaner but AC noise is still the same when I put my ear close to the speaker. No sound at all, nothing happens, 2. 1) heater hum, by means of a bad preamp tube, poor or no center tap ground reference on the PT heater winding. It played for a minute then the sound slowly died off and there was a burning smell coming from the amp. You adjust the pot after you change the tube. Despite its meager wattage, the Monoprice 27222 sounds really good! It's got some heft and a phono stage(!) and when the tubes warm up there's no hiss or hum at all. The amp passes signal that sounds distorted. the sound is effected by any tone stack pot adjustments, just gets bassier/treblier etc in line with the eq controls. I got it for free from a garage sale and the guy said it worked fine but just quit one day. The amp is a very primitive design: class A, 4 tube operation consisting of 5U4 rectifier, push-pull 6L6’s, and 6J5 preamp tube. DO NOT USE ground lift devices to remove the hum, especially when using a tube amp. It sounds like crackling or frying bacon that sort of rides on top of the note, if you know what I mean. if I disconnect the I don't know if this very low level hum is the nature of these tubes. So my best way is to hook up with another preamp to use the volume while setting the tube volume at 1/3. You do not need a cable plugged into the input jack. There are two major reasons why an amp might smell like it’s burning: Common Tube Amp Malfunctions: My amp makes no sound. Keep smilin’, Bill Hruz Hello Bill, Thanks for your question. I still own mine and your post made me remember that mine was acting funny in the beginning. If you`re brave enough, you can So i just opened the amp and tapped on the tubes with a pencil. My nephew brought me his ailing ASI solid state guitar amp to take a look at. The trouble with these lies in the filament line. A quick, simple, non invasive way to address noise issue with the Fender Custom Vibrolux Reverb amp. 082 MFD 600VDC "Outside Foil" 3). How to Fix: Identify the damaged Also added a Lar/Mar PPIMV. The next day I turned it on, unplugged the headphone and no sound. 1k Members; Increasing the amp volume increases the hum loudness. You shouldn`t even be turning the amp on when it`s in this condition. It is a solid state Q-tube 70 guitar amp probably from the 1980's. Components can sound shrill, fatiguing, undynamic and lifeless until broken in. They sound almost exactly like my US pickups, but with no hum. Then I disconnected all the speaker cables and yes there is a “hum” or “buzz” in the amp. No sound with the power tubes out, but when I take out the PI tube, 12at7, I still get noise, FAQ and General Tube Amp Electronics Troubleshooting; ↳ FAQs; Shop Talk; ↳ Technical Discussion; Tap the glass part of the tube with the amp on. I searched through the subreddit but I didn't find anything specific to STL not having sound through Reaper. Muddy sounds of the tube amp could also come from interference or a dirty connection. By Reignman September 19, 2010 in Amps. At gigs this probably isn't loud enough to be a problem, at home it's a bit of a p The amp sounds great, but the only problem is that there is a constant hum coming out of it, it gets quieter as I lower the volume and louder as I raise it. T so the tubes are all glowing, but there's no sound coming out of the amp at all, not even a hum. Members; Mackin. (Tube Amp Doctor) preamp tubes and my amp tech also likes Sovtek for new production tubes. i checked the preamp by using the EXT. Take the Vincent SA-T8 to a friends system and have a listen: - no hum => preamp is fine, maybe the power or connections at your home are problematic - I bet I could easily build a 12AX7 6BQ5 se amp to be less than 1mV hum (12 dB for a small, cheaply manufactured vintage tube amp. They'll sound quite different. I'm wondering though: how much hiss from a tube amp is normal? I'm in the mood to build another tube amp but don't wany any audible hum this time since I now sit very close to my speakers. All good, rocking away. Welcome To the Hoffman Amplifiers Forum January 05, 2025, 12:23:59 am: Welcome, Guest Does your amp make this sound on standby or with no instrument cable Or just general tube amp noise, you could change it the tubes to check but I wouldn't bother unless the noise was really atrocious or obviously out of order. Changing the volume makes no difference. Member. The amp still powers o it increases with volume on tube amp if the phono pre is turned off = no noise tube amp input set to cdp (with phono pre on) = no noise this means, it shouldn't be the tube amp, right? if I disconnect the ground wire to the turntable, the hum remains. I have no idea what a "good" quality stereo tube amplifier would produce, regarding RMS output Probably want that voltage really solid for the best sound - 6. I make no claims about how good any 6AV5G sounds. Please subscribe as I will be uploading new content. NO popping or rattling type of sound - starts to be audible at master=3 volume=3 - hum is significant at master=6volume=3, or master=3volume=6] 3. Humano Sound is a project from the Pacific Northwest intended to honor music in its purest forms—crafted by human hands and preserved on analog formats. if I disconnect one RCA cable (no matter which one), the hum remains. For some years my Cabre AF-25 power amp has been humming through the speakers so annoyingly that listening at low volumes is really unsustainable. Surprised at no difference in hum after installing the IC. The knobs on the amp don`t make any difference either. Troubleshoot Any Zero Volume Hum. Both sounded fantastic once the music started. Posted November 25, 2007. 2020 guitarsoundpro. Yes, hum can originate inside the amp. Top. Phase inverter position preamp tube crapped out. It hums with volume on zero but fages away as I turn to max. The guy who runs Angela Instruments says if you can't take a little hum you should build a push-pull amp. The hum was minimized and it has been a real joy to listen to. The sort of hum you might hear from an old fluorescent lighting fixture. there is a quiet hum, however. Skip to 2023 Repair 0 Comments. 1960's Kay 70 Tube Amp Hum, REALLY Loud Hum 1960's Kay 70 Tube Amp Hum, REALLY Loud Hum. Amp sounds amazing, but after a couple of hours of play time, the V1 preamp tube started to hum quite loudly - even with no input connected. One behavior is like this: All preamp tubes removed except the PI tube. Last but not least, the third setting is the reduction. So, the problem is the power amp side. I swapped out the KT88s for a different set and the hum increased so I went back to the first set to keep the hum at a lower level. That amp was not grounded, and this new amp is. I just got a Scarlett Solo, and it works like it's supposed to in Ableton Live Lite. For more info, Subscribe to this channel, join us at facebook. When that is said every amp construction is different and it may be a pain to cure any hum-problem. So I replace that and fire it up. Mackin. Should have no hum. If tapping a tube Phones, be sure your cell phone is no where near your amp. by adjusting the hum out. Turns out theres pretty strong magnets in my vape to hold battery door shut, etc so id set my vape right where i was playing all the time. I imagine there is some disconnect inside of Reaper and I have no clue how to fix it. I accidentally plugged the speaker out of my tube amp head into the speaker out of my attenuator. Troubleshooting can be a real challenge with extensive setups and signal paths. I recently had a ODS#102 amp lose a tube and it took out the 100r resistors, had the amp used a CT the transformer probably would have gone instead. It is there all the time even with the volume at zero. So I built two tube units to mate with my VTA ST120 tube amp. I suspect its like using a preamp to make the amp sound dirtier. I worked on and off to get rid of the hum. i did pull v3 preamp tube which makes the amp sound a little better but the trem doesn't work. No matter how you experiment with the two gain knobs on the Monoprice it sounds like a rock/blues amp. I'm currently around $70 into this and would love to try out a few easy fixes. However, there No guitar sound. Then one day about to smash my pedalboard and amp, i grabbed my vape to take a hit and the noise stopped. The rectifier is near the transformer, the voltage gets via But if you want to play with a loud, clean, clear fat tube sound, the Blues Jr. But the tube amp only started after I did a total recap, rewire, and HexFreds but the sound was much better. ”In essence, it manifests as a low-frequency sound audible through your speakers, typically characterized as a persistent, unwavering hum or buzz. I can even record and it shows a Solid state amps have no output transformer in most cases. Both power tubes have a rattle i heard at certain notes, one a bit more than the other. M. Lately I also noticed that the right side of Sounds kinda like 60 cycle hum to me, could be a ground loop, and/or poorly shielded parts of the amp, could be a bad tube, lots of things can accept hum from the outside. Lots of AC on the plates with no sound coming out 7. The Jr. Investigating and fixing what's causing the 100Hz hum in my Marshall practice guitar amplifier. Using a Variac, which is a very common device for "starving" amps to produce a particular sound goes back decades. It's always possible that you'll find a bug in it, and I know that there are some situations that aren't covered, although I believe that over 90% of bugs are. Common amp with common issues. It's quite simple, but unique in that it used a transformer as a phase inverter rather than a tube. Joined 2016. Hoffman Amplifiers Tube Amp Forum, 120hz hum problem 5f6a. is able to do that. It is possible that you might plug in a Peavey Valveking 212 amp, but there is no power. short the inputs 4. The amp was completely hum-free after I added the regulator. Posted by u/Cuddy16 - 3 votes and 9 comments Learn ways to fix Tube amp with bad vacuum tubes aka Valves, check if tube is glowing if so is it glowing red, purple or orange? Also check for burnt marks o The amp sounds okay at low volume. thanks so much for your help. Members; 1. People who might think that some amount of hum is normal probably listened to a stereo while either growing up and/or somehow always hearing a bad one or thought that is the way they are supposed to sound, probably hasn't heard what a proper operating tube amp should sound like. Can you try another guitar and verify there isn't a grounding issue with the instrument. Hum disappears when I pull the PI. Moved power tube cathode connection to the negative tab of the cap can that filters both the plate and screens for the power tube section (using an F&T 32/32 can cap here for this) 3. It goes away as your turn the volume up to about 2 or 3, But then returns around 4. Otherwise, the amp sounded exactly the same. For instance, you may hear hum, hiss, reverb crash (if applicable), or even popping sounds when connecting or disconnecting inputs. The hum has these characteristics: - NOT related to the reverb amount - worse after pressing the fat switch - the hum is constant. Tele, MIA Fender Strat x2, Edwards LP Mesa Boogie TC50, Orange Rockerverb Your hum issue being 50 hz can mainly be stemming from three places. Posted November 24, 2007. About -80dB down for hum. i am new to the this thread and so let me say that i have some experience with tube amps. It sounds kind of like bad filtering. Several posters have suggested testing your amp using a 6V lantern battery for the filament supply - this sounds like a relatively simple test and should help determine whether the heater is a source of trouble. I replaced the power supply filter caps, changes and swapped power and preamp tubes etc. Other than this one issue the amp sounds fantastic with a matched set of KT88’s with lots of clean That's actually not all that unusual on one of these and it's challenging to get the hum out of a class A single ended amp to begin with. Amp socket into another amp and that works fine. This is my first tube amp, but I'm aware that tube amp does have some hum. C. com Thanks for your feedback guys! It is a bummer, this is my first real amp (relatively new guitar player, I've played on friends' amp and on a small Fender Frontman), and I was really looking forward to experiencing the legendary tube sound. Motor-like sounds 5. The amp is extremely noisy. Last edited: Feb 25, 2014. Follow along live as I diagnose and repair a 'no sound output' on the Marshall Valvestate VS580 Model 8240 guitar amp. The tube amp has always been dead quiet. I am not sure about hifi tube amps, I can tell you for guitar amp, matching I just bought the Epiphone Century Amp, the 75th Anniversary edition that just came out. Obviously, the 508IA will have much more power. The Monoprice 5W Tube Amp. I got it open to changing the components inside, as sort of a hobby amp. A nice buzz. Are you saying you're running your tube amp without a speaker load connected? If you're sure it's 50Hz hum then it's an issue on the AC side of the amp, either the heater circuit is imbalanced or you have a band ground somewhere. Tube Amp Noise Troubleshooting. clean the tube sockets and the pre-amp plugs 3. Please login or can make it hard to discern the pitch because of all the harmonics of the hum, which is why it sounds buzzy. This is without anything plugged into the amp, and using the clean channel (no gain). Still no sound at all. Which one would sound better is subjective. 002 cap jumps that resistor with no change. To get to the bottom of the noise I subbed a good pair and no more red plating but still distorted and one tube sounded microphonic. This video is about sharing an amp noise issue that I experienced with my AWESOME EVH 5150III 50 watt 6L6 amp head. I have build small SE tube amp using 6L6 and I can hear undesired audible hum from it. Reply. Sort of an on/off, but does allow trickling. Sound is obviously subjective to the listener, so I can only offer my opinion. Follow me herehttp://instagram Tube amps are going to produce some noise. 1uf cap - no change. 047 MFD 600WVDC "Oil Capacitor" Loud 60 cycle Hum from tube amp. customer insisted on trying to use it. That's definitely audible. It is intended to help narrow down the source of seemingly vague and general problems, so that you can You’ll see in a minute why this wouldn’t be a problem with the amp by itself though. With the volume at 0 there is still a faint humming sound coming out of it. It sounds to me like the adjustable hum balance is the way to go for the greatest opportunity to cancel heater induced hum. The distinctive hum from a valve amp can detract from the listening or For example there is one set of 10 videos "the hunt for buzz and hum" on youtube that was somewhat helpful but the guy that posted it essentially starts with a noisy amp and goes through a bunch of tests and analysis in the 10 videos yet finally just ends up just adding a choke at the end to quiet it down. Take the power tubes out and replace them with a fresh set, bias it up, still no go, lhalf volume persists. Pops but works again I am suspecting the actual Standby Switch is gone bad ? I checked the diodes right after the switch, they are conducting in one direction, not conducting in other. Cute amp and it sounds fine for what I do and it will most likely work for some of my gigs. I never heard any hum from my old amp. Definitely something new for my brain to digest. Hum is there with volume on zero but at lower levels. Thread starter archie2; Start date Feb 25, 2014; archie2 Addicted Member. If I disconnected the interconnects from the preamp, no change. 2k Members; Posted November 24, 2007. // Kindly sponsored by my favorite PCB manufacturer PCBWay! h At 10 it kind of sounds like hearing your next door neighbor using a leaf blower through a closed window. You may notice a slight background hum, however, as the push-pull becomes unbalanced. Gibson LP traditional, DC standard, older PRS CE24 (whale blue), Am. Spec. so check all that stuff. after replacing all tubes,no longer microphonic but still distorted. I would first try swapping tubes channel to channel and see if the hum follows a tube. Try a new rectifier tube. I installed an IC regulated power supply to the 1st phono tube filament. No offence taken, I'm happy to admit it's not my speciality. Analysis: No vintage tube tester will meet those criteria, so if this is your preference for matching, your tube tester will not assist you. BEWARE OF TRYING THIS YOURSELF! VERY HIGH VOLTAGES IN This can result in increased hum, loss of low frequency response, low gain, and sometime a phenomenon known as motorboating, in which the amp makes a continued popping or putting sound. Changing one Hum is the same with or with the pan and pan wires connected. Mesa boogie sovtek I think. Never had any hiss at all. The amp suddenly stops playing, particularly after just having clipped 8. The wiring for the tube heaters, if AC, can generate hum. I’ve taken it apart and made sure everything was ok, but frankly I have no idea what I’m looking at. What your amp may be suffering from is a fairly common problem with fairly standard symptoms - just like yours ! This is the first time I've ever had an actual problem with a valve amp so here goes. suspected output tranny. isRelative Show Me What You Got. I tested my old amp and it does make a very low humming sound. It is so low. The amp has low volume. the amp had 1x 100uf+100uf, 2x 50uf+50uf. If your new tubes or tube amp has a high pitched, variable whining noise then the tubes may just need 20mins use in order to settle. You can help us help you by providing the make and model of your amp, and the schematic if you have it. Tube amp hum problem. 1) RED 80 MFD 150WV, GREEN 20 MFD 150WV, Black Common 2). I adhered to the above described principles when building a tube-amp recently and it has no detectable hum present. THE BAD Im not a fan of the reverb on mine. Still trying to get this RCA 400 tube amp hum to stop. It turned out to be a bad can cap. It introduces quite a bit of hum. Is it a placebo effect? 5) one leg is grounded, so before (in AC) I had the filaments running with sine wave average on zero, and in DC I have the filament running 6,3 Volts above zero: I saved any diode effect on cathode which is running in autobias 1. Welcome To the Hoffman Amplifiers Forum January 12, 2025, 01:36:01 pm: Welcome, Guest. i had that sound in an amp but 50hz + 100hz hum. It was intermittent. No hiss, no hum, nothing. Hissiness or sudden harshness at full or near full volume 6. Should i just go ahead and replace them? So I bought an amp that is a copy of a Matchless Lightning. Both were Stereophile Class A recommended units. I use a Gibson LP tribute with a decent size pedalboard (10 pedals) and play a lot of White Stripe/Black Keys/Blues Rock at home (no drummer). I downloaded the free AmpliTube 5 and I get NO sound output. I developed the 21st Century Maida Regulator to deal with B+ hum in my DG300B. otherwise we would be just guessing at your needs. One preamp tube makes the humming sound i heard before. With this fairly limited information, do you have any thoughts as to what the issue could be? I don’t abuse the amp, but I do set the master volume at 4 or so (11 o’clock) to get a fairly loud clean sound. Perhaps somewhat better. If the guitar has single coils you will definitely have some hum, sounds like you found a better spot for the amp which helps. com. Start new topic; Recommended Posts. To confirm a noisy power tube, merely put the amplifier on STANDBY, remove it from its socket and turn it back on. You have to put your ear all against the speaker to detect the slightest amount of hum. not exactly rocket science, nor much insight into a more nuanced So, I have a 5e3 amp that i built from spare parts. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Not even sure if I would trust it in a plastic enclosure because for 'sound reasons' they might leave things in there that can spill out, some of the old amp repair videos I see, its like opening a old refrigerator that someone unplugged in the garage. This literally has NO sounds for the most part just noise If the tube is not matched, it will hum. I switched to Input 2 in Amplitube and it shows the green bar bouncing up and down when I strum on my guitar. Removing the 12AX7 and replacing a 7025 lowered hum some, but still objectionable. Plug straight in to your amp and move it around the house and see if you can find any place where the sound is gone. Dec 7, 2013 #10 No WONDER I had a I adhered to the above described principles when building a tube-amp recently and it has no detectable hum present. Low wattage amps under 50 watts should be silent from 6ft away, no hum but a little hiss if you put your ear right up to it. All F&T's. It has a single 12AX7 in the preamp (along with a bunch of op amps) and a Mosfet power section. Dirty Connection. When connecting the new SP14 tube preamp there was some hum. When the volume is fully off, there is no hum. No other power consumers on this line. I pull yjr 6j7 ptramp tube and it does decrease but with the tube in it seems strong and sound good and id not weak or distorted. As you check the fuse, it could be burnt out. Tube amps naturally produce more background noise than solid-state amplifiers. It's the most beautiful piece of gear I've come across, and it sounds fantastic - the only issue is that there's an audible hum coming from the amp whenever it's switched on (regardless of whether tubes or headphones are plugged in). EL84 tubes may behave a bit differently than the big bottle tubes but the failure mode has similar characteristic sounds. I powered the radio up slowly last night; it works well sort of (i. (When there are no music playing) and when headphones get power after the tubes switch on i can hear some kind of background hum. The tube chance was V3 from a 12AT7 to a 12AU7 which changed the way the reverb control worked a bit but no effect on the hum. Members; Reignman. Tubey. I have add 2 components (Solid State Preamp and Tube Amp) that hum with no sound. Additionally while you are checking this pay attention to the tube color. How to Accurately Diagnose What is Wrong with Your Vintage Amplifier. I've tapped my tubes and I'm not discerning any particular sound or noise, however, I have not swapped tubes. There could be single or multiple reasons, such as a ground connection going bad, or there might be dirty power, or the lighting This guide describes common tube amp malfunctions and their subtleties, including various types of hum and noise. The hum does not change with the amp volume, and I won't be using it for recording. But those are people that like dirty amp tones, no super clean jazz, chimey tones. Even cheap wall warst can be a source of hum which sound identical to power amp hum. It doesn't change much with the first stages at the left tube. The first two gain stages are at the middle tube, then left side of the right tube, both left tube stages, master volume, last stage and power amp. my jca50 is broken T. Volume control does increases the hum. Bad caps usually make the amp hum, not sit quietly. An interstage transformer drives the P-P 6L6’s instead of a more modern phase inverter tube circuit. So my question is, is this a normal operating characteristic for a tube amp? If so, does it have a degrading affect on the sound? If it is a tube amp if could be a bad tube. Direct Monitor button is off (get dry sound when on). I bought my first tube guitar amp and it is inexpensive and has some cheaply made components. You might have noticed an amp hum with no input, and you’ve Fixing the 'Hum when Nothing is plugged in' fault on a Fender Frontman 212r Guitar ComboThis great 2005 amplifier has a well known fault that it Hums when n Schematic did spec a 7025 low noise twisted filament tube in first phono section. In this guide, I’ll walk you through some of the causes of tube buzz and potential solutions. Few details: - it is PCB based (commercial so I belive PCB is not a source of hum): 6L6 SE Tube Amplifier Kit 10+10W (Stereo)_Power Amplifier Kit_Valve Amplifier Kit_Analog Metric - DIY Audio Kit - toroidal power teansformer is inside the chassis (as well as PCB) I say this because a friend of mine had the same problem once he wanted to use mine. When the creamy tube sound of the guitar amp is disturbed by a crackling or rustling, it can often be very frustrating. so far, i've checked all the cables and they are fine. 3. Hum and buzz. Other than the hum, it sounds much better with the bigger transformer, That will sound like: An externally hosted image should be here but it was not working when we last tested it. Just a loud low hum whether the guitar is plugged in or not. Hum balance pot has no effect, phase switch has no effect. Tom The one exception was some slight hum in the phono section of a homemade tube preamp I picked up years ago. Easy Fixes for Malfunctioning Wurlitzers. ) 1. Understanding the problem of tube heaters and hum is the first step toward ensuring your wiring job will be good enough to give happy results (no hum). Working with STL independent of Reaper it works fine and sounds amazing. Amp still sounds great, no distortion, clean, clear sound, cannot hear the hum even when music is playing at a very low volume. When I turn it on, as soon as it has warmed up it produces a rather loud hum, which is not affected by the volume. An oscillating fan can also cause an issue. (1) The heater supply is usually A. I was playing my Laney LC30 at band practice and noticed my tone was brittle and trebley and after about 10 minutes there was no sound coming from the amp at all. Turning up the preamp volume up or down makes no difference, and hum is the same with the preamp volume off. (A good little rock/blues amp. And whenever I put a 12ax7 in the phase inverter, it makes the amp hum. Hearing the fender "bite", and no noise, actually made me play a lot better. Orange is good, blue is fine but if your tubes look mostly red or the metal base of the tube is red than (wait until they aren’t hot) and replace them. I have a room with track lighting that uses halogen If that works you can either leave the lead there, it does no harm, or you can exercise the sockets with a jack plug and switch cleaner by repeated plugging in and pulling out until the contacts within them open and close as intended. The amp makes no sound. Repairing the Fender Twin Reverb from hiss, buzz, noise distortion. It will cause no damage to run the amp briefly with one power tube missing. Tube amplifiers, renowned for their The amp doesn’t turn on. If the amp is completely silent (no speaker hum or hiss at all) then the problem can be just about anywhere in the amp but you should suspect a bad tube, blown fuse or the power supply in that order. All of the resistors measure within Amp is otherwise running great, but has excessive hum. All of a sudden, half power drop in the volume. a few weeks later he brings it in,very low power very distorted. This tube appears to share duties as a final gain stage, the mid-boost switch network and the Phase Inverter. bad or noisy 6SN7's The amp is like any tube amp in that any tube with excess gas can cause hum as well as a soft and distorted sound. To check for a Basic About of Tube Amp Hum – Before we explore the causes and remedies, it’s essential to grasp the nature of the enigmatic “tube amp hum. What other options to My neighbor, who has no experience with tube amps, and who loves his 700-watt Phase Linear gear, was almost speechless at what incredible sound this little amp was capable of — all while driving into a cheap $30 set of Dayton Audio B652 bookshelf speakers. swapped tubes and trouble followed the tube. i am working on an Ampeg B15 Flipover bass amp. Any tube that is sounding unusual from the rest of the tubes is the root of no sound from speakers. Usually, in a no-sound scenario, you will hear some sound coming from the speakers, even if the signal path happens to be cut off. The hum is present with the volume turned all the way down. you can easily get killed by some leaking overheating bullshit in a tube amp from 1940. So before doing anything drastic, check that first. makes no difference if I plug in a jack cable or not into the front end, no increase or decrease in hum. The noise I experienced was an intermitte No. ChopSauce I have the amp on a dedicated 20 amp circuit which was quiet as a mouse with the SS amp that was on it before this amp, which eliminates it being a ground loop. It was a bad power tube that became {censored}ty after it warmed up for a bit. Members; Dave Owens. Quote from: dude on May 29, 2016, 03:48:06 pm. Matador Well-known member. Either on my amp, or on edge of pedal board, etc. there is no guitar sound when it is connected. 2. The buzz goes away when I remove v2 the distortion tube. Yes there is a very slight “hum” in the amp and it’s also coming from the speakers. Users have complained that they have to do a thorough search here and there before getting their hands on A lot of amps, both tube and solid state, will experience failure in electrolytic caps, particularly ones made during the "Capacitor plague" era of the early In my case I was trying to resurrect an amp that wouldn’t stay powered on for more than a few seconds, so I initially set the bias with no power tubes installed at all, and then tweaked it with them in once I got over the immediate blowing of the fuse. Any ideas what could be causing it I recently purchased a Kenzie Encore tube headphone amp from @Eagleeyes. gnufj djqiw htfat zjjxae jxopoa kte mvbitc njsum acwy pwvf