A Peavey Classic 50/410 combo suffers from a swirling hum.
Your answers to questions in Premier Guitar have left me me to believe that you might know what I am hearing when I use my Peavey Classic 50/410 combo. I love the tone that I get, but there seems to be an intermittent swirl sound that happens while I am playing. It doesnāt affect the amped signal, but is in the background. Sort of like a spacey, swishing hum from a bad ground. I have taken a mirror and tried to watch the tubes to see if one is having a fit and have seen nothing. I want to get the clean sound and not have that underlying noise. It doesnāt matter if I am on channel one or two, have reverb on or off, in bright or normal channel. I have it just through the combo or with the 410 extension cabinet. Also here in Central Illinois, I donāt know of any good techs to take it to for repair. If you could give me an idea what it is that is wrong and where to start looking to get this fixed I would really appreciate your advice. I just looked at the web site for Mercury Magnetics upgrades and was wondering if you had any experience with their claims. Sounds good, but is it worth it?
Dan
Hello Dan,
Thanks for reading Premier Guitar and also my āAsk Amp Manā column. Glad you enjoy it.
There are a couple of possible causes for such a symptom. I would say the first, and most easily remedied, would be a faulty tube. Many different types of noises can come from tubes, none of which could be visually determined. The first thing I would recommend would be to clean the sockets and replace the EL84 output tubes in the amp. These tubes take the most beating and should be replaced more frequently than the preamp tubes. You did not mention the last time you had done this, but a good rule of thumb nowadays is six months to two years, depending on how often and how loud you play.
In order to clean the sockets, obtain some electrical contact cleaner that does not contain lubricant. Remove the tube, spray a decent amount of cleaner into the socket and cycle the tube in and out of the socket six to ten times. Leave the tube out of the socket and move on to the next socket. When all the sockets have been cleaned, leave the tubes out and give the sockets ample time for the cleaner to evaporateāmaybe fifteen to twenty minutes. Install the new tubes, fire up the amp and see if this has cured the symptom. If not, I would next replace the 12AX7 preamp tubes. One thing to remember, however, is that a new preamp tube can also produce different types of mechanical or microphonic noises. If your original symptom has been eliminated but the amp is now producing a metallic ringing or starts feeding back, move around the location of the preamp tubes to see if you can place the offending tube in a less sensitive location. If neither of these alleviates the symptom, at least the amp has a fresh set of tubes and should sound great once the cause has been found and the problem remedied.
To further explore the possible causes, I posed your question to John, an engineer friend of mine at Peavey, and I believe we may have another possible answer for you. The Classic 50 uses a wire connecting the preamp circuit board to the output tube circuit board, which provides the ground connection to the output board. This should be a black wire utilizing a white plastic connector approximately one inch long and attached to J74 on the output board (if marked). The recommended way to repair this potential cause of the problem is to upgrade the connection by removing the connector, stripping the wire and soldering the wire directly to the pin on the circuit board. This will provide the best, most reliable ground connection, without the worry of oxidized or intermittent connectors. This may be a larger task than most players are capable of and servicing tube amps should not be undertaken by anyone unfamiliar with the hazards, so find an experienced service technician to perform this kind of work. Regarding your question of such a technician in Central Illinois, I personally do not know anyone in that area. However, Iām sure if you inquired in any of the various gear forums you would find someone who is trusted.
To the last part of your question concerning the Mercury Magnetics upgrades: I have used their replacement transformers in the past and they definitely make a wonderful product. While I have not had the opportunity to install one of their recent upgrade kits, I have heard from players who have had the opportunity to compare stock and upgraded amps side by side, and they tell me the difference is quite noticeable. One even found it hard to believe they were the same model ampsāso Iād have to say that if you have a discerning ear, it may be a worthwhile investment for you. I hope that helps you restore your Classic.
Jeff Bober
Co-Founder and Senior Design Engineer ā Budda Amplification
jeffb@budda.com
budda.com
Ā©2008 Jeff Bober
Selenium, an alternative to silicon and germanium, helps make an overdrive of great nuance and delectable boost and low-gain overdrive tones.
Clever application of alternative materials that results in a simple, make-everything-sound-better boost and low-gain overdrive.
Might not have enough overdrive for some tastes (although thatās kind of the idea).
$240 street
Cusack Project 34 Selenium Rectifier Pre/Drive Pedal
cusackmusic.com
The term āselenium rectifierā might be Greek to most guitarists, but if it rings a bell with any vintage-amp enthusiasts thatās likely because you pulled one of these green, sugar-cube-sized components out of your ampās tube-biasing network to replace it with a silicon diode.
Thatās a long-winded way of saying that, just like silicon or germanium diodesāaka ārectifiersāāthe lesser-seen selenium can also be used for gain stages in a preamp or drive pedal. Enter the new Project 34 Selenium Rectifier Pre/Drive from Michigan-based boutique maker Cusack, named after the elementās atomic number, of course.
An Ounce of Pre-Vention
As quirky as the Project 34 might seem, itās not the first time that company founder Jon Cusack indulged his long-standing interest in the element. In 2021, he tested the waters with a small 20-unit run of the Screamer Fuzz Selenium pedal and has now tamed the stuff further to tap levels of gain running from pre-boost to light overdrive. Having used up his supply of selenium rectifiers on the fuzz run, however, Cusack had to search far and wide to find more before the Project 34 could launch.
āToday they are usually relegated to just a few larger industrial and military applications,ā Cusack reports, ābut after over a year of searching we finally located what we needed to make another pedal. While they are a very expensive component, they certainly do have a sound of their own.ā
The control interface comprises gain, level, and a traditional bright-to-bassy tone knob, the range of which is increased exponentially by the 3-position contour switch: Up summons medium bass response, middle is flat response with no bass boost, and down is maximum bass boost. The soft-touch, non-latching footswitch taps a true-bypass on/off state, and power requires a standard center-negative 9V supply rated at for least 5 mA of current draw, but you can run the Project 34 on up to 18V DC.
Going Nuclear
Tested with a Telecaster and an ES-355 into a tweed Deluxe-style 1x12 combo and a 65 Amps London head and 2x12 cab, the Project 34 is a very natural-sounding low-gain overdrive with a dynamic response and just enough compression that it doesnāt flatten the touchy-feely pick attack. The key adjectives here are juicy, sweet, rich, and full. Itās never harsh or grating.
āThe gain knob is pretty subtle from 10 oāclock up, which actually helps keep the Project 34 in character.ā
Thereās plenty of output available via the level control, but the gain knob is pretty subtle from 10 oāclock up, which actually helps keep the Project 34 in character. Settings below there remain relatively cleanāamp-setting dependent, of courseāand from that point on up the overdrive ramps up very gradually, which, in amp-like fashion, is heard as a slight increase in saturation and compression. The pedal was especially fantastic with the Telecaster and the tweed-style combo, but also interacted really well with humbuckers into EL84s, which certainly canāt be said for all overdrives.
The Verdict
Although I almost hate to use the term, the Project 34 is a very organic gain stage that just makes everything sound better, and does so with a selenium-driven voice thatās an interesting twist on the standard preamp/drive. For all the variations on boost and low/medium-gain overdrive out there itās still a very welcome addition to the market, and definitely worth checking outāparticularly if youāre looking for subtler shades of overdrive.
Some of us love drum machines and synths, and others donāt, but we all love Billy.
Billy Gibbons is an undisputable guitar force whose feel, tone, and all-around vibe make him the highest level of hero. But thatās not to say he hasnāt made some odd choices in his career, like when ZZ Top re-recorded parts of their classic albums for CD release. And fans will argue which era of the bandās career is best. Some of us love drum machines and synths and others donāt, but we all love Billy.
This episode is sponsored by Magnatone
An '80s-era cult favorite is back.
Originally released in the 1980s, the Victory has long been a cult favorite among guitarists for its distinctive double cutaway design and excellent upper-fret access. These new models feature flexible electronics, enhanced body contours, improved weight and balance, and an Explorer headstock shape.
A Cult Classic Made Modern
The new Victory features refined body contours, improved weight and balance, and an updated headstock shape based on the popular Gibson Explorer.
Effortless Playing
With a fast-playing SlimTaper neck profile and ebony fretboard with a compound radius, the Victory delivers low action without fret buzz everywhere on the fretboard.
Flexible Electronics
The two 80s Tribute humbucker pickups are wired to push/pull master volume and tone controls for coil splitting and inner/outer coil selection when the coils are split.
For more information, please visit gibson.com.
Gibson Victory Figured Top Electric Guitar - Iguana Burst
Victory Figured Top Iguana BurstThe SDE-3 fuses the vintage digital character of the legendary Roland SDE-3000 rackmount delay into a pedalboard-friendly stompbox with a host of modern features.
Released in 1983, the Roland SDE-3000 rackmount delay was a staple for pro players of the era and remains revered for its rich analog/digital hybrid sound and distinctive modulation. BOSS reimagined this retro classic in 2023 with the acclaimed SDE-3000D and SDE-3000EVH, two wide-format pedals with stereo sound, advanced features, and expanded connectivity. The SDE-3 brings the authentic SDE-3000 vibe to a streamlined BOSS compact, enhanced with innovative creative tools for every musical style. The SDE-3 delivers evocative delay sounds that drip with warmth and musicality. The efficient panel provides the primary controls of its vintage benchmarkāincluding delay time, feedback, and independent rate and depth knobs for the modulationāplus additional knobs for expanded sonic potential.
A wide range of tones are available, from basic mono delays and ā80s-style mod/delay combos to moody textures for ambient, chill, and lo-fi music. Along with reproducing the SDE-3000's original mono sound, the SDE-3 includes a powerful Offset knob to create interesting tones with two simultaneous delays. With one simple control, the user can instantly add a second delay to the primary delay. This provides a wealth of mono and stereo colors not available with other delay pedals, including unique doubled sounds and timed dual delays with tap tempo control. The versatile SDE-3 provides output configurations to suit any stage or studio scenario.
Two stereo modes include discrete left/right delays and a panning option for ultra-wide sounds that move across the stereo field. Dry and effect-only signals can be sent to two amps for wet/dry setups, and the direct sound can be muted for studio mixing and parallel effect rigs. The SDE-3 offers numerous control options to enhance live and studio performances. Tap tempo mode is available with a press and hold of the pedal switch, while the TRS MIDI input can be used to sync the delay time with clock signals from DAWs, pedals, and drum machines. Optional external footswitches provide on-demand access to tap tempo and a hold function for on-the-fly looping. Alternately, an expression pedal can be used to control the Level, Feedback, and Time knobs for delay mix adjustment, wild pitch effects, and dramatic self-oscillation.
The new BOSS SDE-3 Dual Delay Pedal will be available for purchase at authorized U.S. BOSS retailers in October for $219.99. To learn more, visit www.boss.info.