Members Jazzer2020 Posted October 20, 2018 Members Share Posted October 20, 2018 I was just in a store testing out a Fender Blues Junior tweed amp.I liked what I was hearing except for a faint high freq. noise.I brought in my Gibson ES-175 P90 guitar to test it.I didn't do a lot of testing with the dials but I couldn't seem to dial out this high freq.(hf) noise.I had mid and bass turned up and highs way down. I suspect it has something to do with the P90 pickup. I plugged in a Fender Strat to see what would happen.When each pickup was activated the hf noise was also there.But when I went 'between' pickups with the selector switch, the hf noise disappeared. This is the amp:https://www.long-mcquade.com/54471/G...nsen-C12-N.htm I had them order one in for me despite this. Will take a few weeks. When you move to the side and away from the amp it is not really noticeable. Is there something that can be done with the amp to filter out this hf? Link to comment Share on other sites More sharing options...
Members Mikeo Posted October 20, 2018 Members Share Posted October 20, 2018 I have this exact amp. I will stop in later after thinking about a few things. It's not a dark amp. If you are looking for the classic Fender Tweed sound from the 50's, this is not it.The amp you really want is the Fender '57 Custom Deluxe 12W 1x12, but it's 2 grand.4x the cost of the BJ Tweed NOS. I was seriously thinking of getting a 57 Deluxe myself, however I have a dozen amps. I don't have an ES 175 with P90, but I have an ES 275 with Humbuckers, and a SG with P90's. I also have a couple of Godin 5th Ave's with Godin P90's knocks pup. I'll play with em all tomorrow and see what I think. We'll chat down the road. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 21, 2018 Author Members Share Posted October 21, 2018 I have this exact amp. I will stop in later after thinking about a few things. It's not a dark amp.... We'll chat down the road. Thanks for stopping by Mike! I was just really looking for a tube home amp for practice. I have two great sounding amps, ready for gigs (Fender Princeton II and Headstrong Lil' King). I just want to keep them fresh and spare them the home workouts. So the 'Fender Tweed sound' is not that critical really. And besides the high freq noise/squeal, the rest of the sound was great actually. As I mentioned, I turned the Treble way down and the Mid/Bass way up as that's how I normally set up my amps. I think the fact that the noise disappeared completely with the 'out of phase' pickup selection I made with a Strat (at the store) is significant in this equation. There's also the possibility of course that the amp I tried (was new) was, shall we say, a little "off". Link to comment Share on other sites More sharing options...
Members onelife Posted October 21, 2018 Members Share Posted October 21, 2018 If the noise goes away when you turn the Volume control on the guitar down (and I suspect thst it will) then the problem is not in the amplifier. P90 pickups are noisy as are single coil strat pickups. Modern strats have reverse wound middle pickups so when the 'in between' positions are selected the pickups are in humbucking configuration - which, in your case, also points to the noise problem being outside of the amplifier. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 21, 2018 Author Members Share Posted October 21, 2018 If the noise goes away when you turn the Volume control on the guitar down (and I suspect thst it will) then the problem is not in the amplifier. P90 pickups are noisy as are single coil strat pickups. Modern strats have reverse wound middle pickups so when the 'in between' positions are selected the pickups are in humbucking configuration - which, in your case, also points to the noise problem being outside of the amplifier. Thanks onelife for your help. You say the guitar, I say the amp. I think we could both be right. Here's why. I don't get this hf noise on any of my amps at home with this same guitar. Link to comment Share on other sites More sharing options...
Members onelife Posted October 21, 2018 Members Share Posted October 21, 2018 Single coil high impedance guitar pickups are subject to electromagnetic interference that travels through air. It sounds to me like there is more electromagnetic interference in the store than there is at your home. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 22, 2018 Author Members Share Posted October 22, 2018 Ahhhh... that could very well be it! I'll see in a few weeks. Link to comment Share on other sites More sharing options...
Members WRGKMC Posted October 22, 2018 Members Share Posted October 22, 2018 If it was a hum issue due to being single coil pickups you'd have either a 60 or 120Hz hum. Hum can extend up into the higher frequency bands with its harmonics but the bass frequencies would be fare more noticeable. This doesn't sound like the problem to be and given its a Gibson its likely to have decent shielding even if they are p90's My thoughts when I read the post are Feedback relates. Hollowbody and semi hollowbody guitars typically have issues with microphonic feedback. P90's are not potted with wax which can make them even more susceptible. I'm not sure how loud the OP was playing but this can be a problem even at low volume if the amp has the input preamp gained up to overdrive the sound. The pickups can act just like a PA microphone and feedback with a high frequency resonance depending on how loud the amp is set. The way you know is by placing the guitar close to the amp's speaker. If the feedback grows into a loud howl, you know its the pickups and/or guitar body resonating. If the volume on the guitar lessens it you definitely know its coming from the pickup, not the amp. you could also use another guitar with the amp to rule it out too. In some rare cases I have seen a guitar cable go microphonic and create strange sounds. This typically happens if the cable is super low quality or after its been overheated from using it as a speaker cable. A guitar cable is only good for 1 volt and a few milliamps. When connected to a speaker you fry the thing from the inside out which melts the plastic inside and lest oxygen in. It oxidizes and begins to make all kinds of strange sounds, even becoming microphonic. Guitars with single coils are the worst because there isn't any humbucking to kill noise from the cable or pickups. Easiest way to know for sure is to use deductive reasoning and rule swap things one at a time till you find the cause. If that doesn't work and this is a tube amp then it may be the amp has microphonic tubes which can happen whether the tubes are new or used. . Link to comment Share on other sites More sharing options...
Members onelife Posted October 22, 2018 Members Share Posted October 22, 2018 If it was a feedback issue, as you suggest, then switching the strat to humbucking configuation would not make a difference. Link to comment Share on other sites More sharing options...
Moderators daddymack Posted October 22, 2018 Moderators Share Posted October 22, 2018 were there fluorescent lights in the store? They are notorious for creating the high frequency sound you are describing when using un-shielded single coil p-ups like P90s in a hollowbody.. Humbuckers are not as susceptible to it, so when you switched to the Strat's hum canceling position, the disappearance of that tone makes sense. I own 2 Blues Juniors, and these are giggable amps. For home practice, something in a 1W to 5W range [i have a Fender Champion 600, an old Magnatone lap steel amp and a Valve Junior for home practice and recording] would probably be better, since Blues Juniors like to be pushed.If the amp does this at your home, which I doubt, a low pass AC line filter will correct it. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 22, 2018 Author Members Share Posted October 22, 2018 Right onelife, that certainly wasn't the issue.The input gain was set to the minimum (1) and the master was up to about 2-3.I rarely overdrive an amp. Clean is best for my style. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 22, 2018 Author Members Share Posted October 22, 2018 I didn't notice the lighting system, but the amps are chained on the same power outlet so that could be part of the problem.Yes, I am sure I could gig with this amp too. My other amps are around 22W output.I have good sounding transistor amps I also use at home, but I wanted a tube amp soundthat I didn't mind using every day.Thanks for the tip about the AC line filter. I'll let you guys know how it turns out in a few weeks. Link to comment Share on other sites More sharing options...
Members onelife Posted October 23, 2018 Members Share Posted October 23, 2018 May I suggest you check out the Boss Katana 50 as a possible home practice amp? It has an output power selector that can be set as low as 1/2 Watt and the tube emulation is very good - but without any of the undesirable qualities such as microphonics and unwanted noises. It is inexpensive and lightweight as well.as maintenace free. https://www.long-mcquade.com/74288/Guitars/Guitar-Amps/Boss/KATANA-Guitar-Amplifier-50watt-1-12---Speaker.htm?ref=suggestive-search Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted October 25, 2018 Author Members Share Posted October 25, 2018 Thanks onelife, I'll have to check it out more carefully when I get a chance again.A few months ago in the summer I was in another music store and was trying out a nylon string electric/acoustic guitar. I plugged it into a Katana 50 but wasn't impressed with the sound I was getting. It was very 'glassy' to me, not warm at all. I'll bring in one of my guitars and see if it sounds any different with that. Link to comment Share on other sites More sharing options...
Members onelife Posted October 25, 2018 Members Share Posted October 25, 2018 I too found the K50 to be a bit glassy (I used the term 'harsh') when I first started using it. The K100 - more expensive - has a Presence control that tames that quite well. After spending some time with mine and getting to know the characteristics of the different amp models I able to get a nice fat warm tone - even with a telecaster. My 'jazz box' is Gibson re-issue ES-295 w/P100s. I replaced the Bigsby with a 335 tailpiece and strung it with flatwounds. It's a good match with the Katana 50. Link to comment Share on other sites More sharing options...
Members Jazzer2020 Posted November 24, 2018 Author Members Share Posted November 24, 2018 Well I thought I'd give an update on the HF problem. The new amp came in a couple of weeks ago and that's when I picked it up. The more I play it the better it sounds. There was no HF noise here at home, thankfully. The amp does have a slight hum/hiss, but that's the nature of the beast and isn't noticeable when playing. I'm a very happy camper now. Link to comment Share on other sites More sharing options...
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