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psarkissian

Service Engineer Moderator
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Everything posted by psarkissian

  1. Have a Variax 300 Electric and four JTV's,.... Love 'em, never had problem with any of them.
  2. Oh and BTW,... We staff monitor and help where needed, but this is mainly a user forum. Sorry if you think we've somehow been neglectful.
  3. So now,... as to the problem you are have with the guitar. possibilities,... -Burr in the nut slot -Loose hardware vibrating somewhere -Set Up issue, string action height -Pick ups set too close to the string -Failing piezo element Have it checked by your local Line 6 service center. Lester being the higher gain Model in the bunch, it would break up sooner going thru a higher gain setting. If there is a mechanical reason such as set-up, the processing would bring this out more. Geamala, seems like it needs to have an adjustment dialed in. I'll know better on Monday when I can use my work computer. The one I'm on doesn't do SoundCloud files.
  4. I posted info here. I conitnue to follow a number of post. I get notices when a comment is added. If it has been a while, then it may because it has been a while since the last post, til now. I post info and give my advice as a technician regarding product. I have no control over what is done with my advice. It's either taken and used, or it isn't.
  5. No particular reason. There are a number of threads about multiple same subjects. And new ones on same subjects pop up. Each one may, or may not have some detail not in the others. I respond to the one that comes up, when it comes up. Doing a search on a subject before doing a post, would more than likely reveal that. And some of them are so out-of-date as to be not very useful. So I try to keep people here up to date on things. I'm a service and repair tech, a circuit geek. They let me browse thru here from time to time, so long as it doesn't interfere with my repair and service duties. So I don't get to monitor the Forums constantly, just when I can and have a moment. Subject searches, Knowledge Base and User Manuals are a good start fo info serches. Good that you found the other postings. Some are still useful, some are out-of-date. Just a matter of sifting thru it to find what you're looking for. Abundance of info,.... the blessing and curse of the internet. Hope your searches are fruitful.
  6. Ducking is usually done with a shelving filter.
  7. Also, if you change the gauge of string when changing strings, that will change the tension on the neck, and you would need to get your set-up adjusted to that tension.
  8. Need to dial-in the set-up a smidge. If it's a howling or whistling ring, the intonation needs dialing-in a smidge. Also, make sure the pick-up are not too close to the strings, beat frequencies from warbling can also occur if the pick-up height is off. Check the string nut for burrs in the nut slots, they can sometimes have the same affect as fret buzz vibrating against a burr. Have an authorized Line 6 service center deal with it, they'll have access to service info. Doing a set-up on a JTV has the added quirks of dealing with both piezos and magnetics together. Have an authorized service center do it.
  9. Not sure, possible,... the tubes are acquired in batches, and there will probably be minor variation from batch to batch. One batch may be harder or softer than the another, note "er". And yet, remain within a region that the amp likes. There are periodical reviews of the tubes, and I chat with Mike Matthews (owner of EH) about tube stuff every year at NAMM, to get a heads up on his tube stuff.
  10. SET SCREW, 4-40 x .125", STEEL CUP POINT. Has to have the cup point or it won't lock the Trem bar correctly.
  11. --- Tube amps want to see a load on their outputs. Never turn on a tube amp if the speakers are not connected. --- Is it true that the tubes work well only when the volume is high? No. They work well when they used correctly. --- Is it okay to connect the Spider Valve speakers to an external amp head by disconnecting from the Spider Valve amp? If, and only if,... the other speakers have the correct impedance rating marked on it and they are correctly connected as such. Amp output impedance and speaker impedance have to match, including the correct kind of speaker cable (which has its own impedance). All impedances have to be matched. Disclaimer and caveat--- However, not a good idea to do this, too many variables, too many things can go wrong. So we recommend not doing that. If the speakers get damaged and you re-connect the amp to its own speakers, the amp can get damaged too. --- If so do I need to have the Spider Valve amp on or off? Yes, turn it off... or it will end up on my bench for repairs, or the bench of one of my lab mates. Disclaimer and caveat 2--- However, not a good idea to do this, too many variables, too many things can go wrong. So we recommend not doing that. If the speakers get damaged and you re-connect the amp to its own speakers, the amp can get damaged too.
  12. Part of it also has to do with the proportion of vacuum vs gas. Soft--- more gas (a gassy tube), less vacuum, saturates more easily, so it distorts more easily. Hard--- less gas, more vacuum, higher saturation point, harder to distort and so more headroom. Medium--- in between, has good headroom, but will distort if you push it. That and the proportion of plate current (Ip) verses transconductance (Gm) are determining factors.
  13. It's more physics in general industry than OEM, though the OEM may have their own augmentations and preferences as an adjunct to that standard. It's a sliding curve range, proportional to the plate current (Ip) and transconductance (Gm), within that variety of tube, that determines hard, medium or soft. I'm preparing a posting for the Knowledge Base on the subject of vacuum tubes as it relates to our product.
  14. Been in touch with a guy at EH, just to confirm. We have a mix here in repair of the EL84EH, for the DT25's. The plate currents (Ip) are less than 30. Upper 20's (25 and up) to 30 are Hard, we have some between 20-24 which are Medium, and we have a few at less than 20 which would be Soft. DT50 series uses EL34EH, so the ranges will be a little different.
  15. The latest JTV Firmware is version 2.21 for all JTV's and the Variax Standard.
  16. Check with Line 6 customer support and log a ticket in your account. Your serial number may fall within range of a few things, so it should be checked to see if they were done to the unit.
  17. Probably a loose connection inside, take it to an authorized Line 6 service center. DO NOT, DO NOT, DO NOT try to do this yourself. There is a supply line voltage there, and it hurts like hell when you get zapped by it,.... even with the power off. DO NOT go in there yourself, have a tech who knows this product deal with it.
  18. Yes. Thin, light and easy along the rim, nothing fancy. Pull the knob off and re-glue it, let it set for an hour or two before putting the knob back on the shaft.
  19. Oh, and BTW,... it's a good idea to use a variable AC (or VariAC) when biasing any tube amplifier in general,... including the DT series amps, and maybe our other tube amps as well. Wall mains can vary a little bit from region to region. Just generally a good practice.
  20. Don't forget, there is a Return Level control on the back of the head. It inserts into the signal path prior to the pre-amp tubes.
  21. "One thread suggested contact spray on the buttons and pressing the buttons repeatedly to work the spray down into the switch"--- please don't do that. I will leave residue on the insides. And some of those contact cleaners are bad on plastics. Log a ticket in your account, get a return authorization. It should be serviced by a Line 6 authorized service in your area so they can check a few things.
  22. I don't have a spec on that. I'll have to check with someone and get back to you.
  23. stevekc suggestion is a good place to start. He knows his stuff. One of five people in the Americas (north or south) I trust to do a mod on a JTV, ... without messing it up. Work on one of his Bigsby JTV-59's,... ... nice. If it's in the "on" position, chances are it's just an alignment thing. If the volume of tone control knobs are loose, then it's just a matter of pulling off the knobs, testing the knob excursion for each position is good, then tightening the nuts down. There is also a spacer fix for that. A Line 6 authorized service center could deal with that or get a knob with the in it. Being an authorized service center, they would check out all the other things as well, as they would have access to service info and service manuals. Both of the above mentioned are simple and straight forward. If the encoder is jammed underneath, the pick-guard would have to come and that is a bit more involved. There could be a couple of reasons for that, including a failed encoder. In any case, it should be looked at by someone who knows the product. At this point giving a ballpark idea would not be possible until a better idea is regarding the above mentioned possibilities. They are just too wide and varied. BTW, what's the serial number of the JTV-69?
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