clubhouse wrote: ↑Mon Feb 20, 2023 11:25 am
PS: with the meter reading about 1.5 ohms measured across the speaker plug compared to across the speaker terminals...is that food for thought in amp design/electrical engineering or a well accepted loading issue when pairing trannies to valves and speakers?
The resistance of speaker cable is generally the reason why you want a beefy wire gauge and should avoid guitar signal cable. Speakers are relatively low-voltage, high-current so any resistance can result in significant dissipation. However, most standard multimeters (even Fluke) are not very accurate at <2 ohms or thereabouts so values like youre getting are basically not significantly different to zero. Remember that the wire leads of your meter have their own inherent resistance, plus the tips of the probes and the object you’re measuring can have surface dirt, oils or oxidation, which adds more resistance, etc. This stuff is all academic though- interesting perhaps but not worth worrying about. Anyone who tells you they can hear the difference between speaker cables for a guitar amp is probably in business selling speaker cables!
Again, thanks for the clarity! Pointing out the resistance in the measuring tools and contamination and the accuracy of the tools clarifies the issues to me a lot. Seems, thankfully, there's a bit of tolerance in the valve amp that can accomodate a degree of mal-handling before failure...but I'll still stick to your advise and accepted safe practice to keep the magic smoke as contained as possible
Here's a meter myself & son have been using for about 12 months now. Behaves quite well and robust, accurate far as I can tell. This one's out of stock now but check the others.
