I have seen other threads and comments about MT15 effects loop noise. I use the effects loop every day for years and never noticed any noise. In response to your question, I unplugged my effects loop as a quick test, and found that there is a tiny hum with the effects loop connected, but honestly I don't know if the hum is coming from the loop in the amp or the effects in the loop. Regardless, even while playing clean, the hum is not bad.
MT15 Replacement Power Tube Selection
- Thread starter scott_
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I have seen other threads and comments about MT15 effects loop noise. I use the effects loop every day for years and never noticed any noise. In response to your question, I unplugged my effects loop as a quick test, and found that there is a tiny hum with the effects loop connected, but honestly I don't know if the hum is coming from the loop in the amp or the effects in the loop. Regardless, even while playing clean, the hum is not bad.
D
Deleted member 5962
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I end up saying the same thing in every thread about the Archon loop. Mine WAS noisy at first, but I tracked that down to one pedal. Removed that pedal and it's just not enough to even mention. Very slight, not at all objectionable noise.
The other thing I say in EVERY thread about effect loops being noisy, is that there is a thread about noisy loops about every amp ever made, and ALL will have multiple users saying they don't have the issue. At some point, you figure out what that means...
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Goran Lorencin
New Member
What do you mean with "At some point, you figure out what that means..."?
Update: I chose to replace the Ruby tubes with TAD 6L6WGC-STR (small bottle 6L6). I chose the TAD because, it is a highly-available alternative with specs that seem to closely match the Ruby tubes. The TAD tubes cost a little more than the cheapest alternative, and are far less expensive that more exclusive and NOS options. I ordered a TAD factory matched set. The TAD 6L6WGC-STR tubes look almost exactly like the PRS OEM Ruby tubes. Based on side-by-side inspection, the only visible difference other than lettering, is the bottle height. The TAD bottle is negligibly (2-3mm) taller than the Ruby bottle. To avoid "hot" related sound qualities, I aimed for a bias setting on the low-mid point of the 25mv-30mv range specified by PRS. Immediately after installation, I measured about a 1.5mv variance between the two TAD tubes. With the 1.5mv variance, the tubes were initially set to about 26mv & 27.5mv. During the first several hours of use in clean or slightly over-driven play, the sound was clearly harsh and shrill. There are countless internet discussions about the need to "burn-in" new tubes. Some say it's a myth. However, I am certain that burn-in 100% necessary and the amp will not sound good until new tubes are burned-in. During the first 20 hours of play, the bias readings drifted down by about 2-3mv, and the harsh/shrill sound slowly "burned" away. During that time I routinely adjusted bias back up toward my 27mv target. After about 30 hours of play, the sound is fantastic and the bias gap has closed down from 1.5mv to about 0.2mv. Since my Ruby tubes still work, I swapped them back in for quick comparison, and I cannot detect an audible difference between the OEM Ruby and TAD after burn-in. I'm very happy with TAD 6L6WGC-STR tubes in the MT15. The only thing I would do differently, is order the tubes from a vendor who can burn them in prior shipping for an extra cost.
