Bob Latino wrote:XLR inputs for the M-125 monoblocks ? The general rule with all the VTA amps is that if what you want to add in does not impact the sound quality of the amp, you won't get this item with the standard VTA M-125 kits. No XLR inputs, no VU meters, no bias meters, no autobias boards and no tube cage. None of these 5 items will make any real impact on or "upgrade" the sound of the amps. To my knowledge, there are no other USA made 125 watt tube monoblock amp KITS.
Read the link below about a comparison of the VTA M-125 with the original Dynaco Mark VI.
VTA M-125 vs. Dynaco Mark VI
I get the philosophy of not adding unnecessary complications, but it's not really fair to lump balanced inputs into the same category as VU meters. In the first place an XLR is inherently just a better, more reliable connector. In the second, common mode rejection can make a difference in hum or noise pickup or ground loops even at line level, though it doesn't appear to in my particular case. I have definitely had situations with buzz using unbalanced runs but not with balanced. Some people feel balanced connections sound better, possibly from low level noise not specifically audible by itself, but it does necessitate either an extra transformer or more complicated circuitry.
You're right about tube cages not improving sound. They can also interfere with ventilation and cause heat build-up, depending on the design, as well as interfere with the visual appeal of the glowing tubes. However, they can make equipment more child safe or pet safe. I once had a cat land directly onto a hot griddle. He appeared to be unscathed, and never repeated that mistake. My current cats haven't learned any hard lessons so far from the amps that I know of. If they did, I expect the worst consequence would be a nose burn that would heal. Still if there were coarse cages available, such as used by PrimaLuna, I'd consider them, but I'm not worried enough to consider fabricating them on my own.
I have a clear memory of about age 3, touching a tube of my Dad's Pilot integrated amp (never saw that brand in my vintage equipment browsing but I grew up with it). Since I clearly wasn't supposed to do that, I was able to conceal the 2nd degree burn blister I got from it. I survived, and never repeated that mistake. The amp lived in a cabinet next to records, which occasionally would lean on the amp and get melted.
From your link, it looks like my memory of the MK VI was incorrect. It used a pentode voltage amp and split load phase splitter. Pins 1 and 2 are just tied together (though it's hard to see from the text printed over it). You still got to use a better connector though.