I realized I've been listening and testing these in balanced mode with the pleasenator circuit in the loop. Time to find out what happens when they are turned off. Realized this when testing SE operation and kept seeing fuzz on the sine wave. Sometimes, I wish I had a little more Capt Obvious bubbling at the surface. Put some signal processing theory to the test this coming weekend.
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I may be wrong, but I think that by the “pleasenator circuit” 6sx7 is referring to the portion of the circuit that adjusts 2nd harmonic content with the multifarad cap and resistor which can be jumpered in or out. At least I hope so.
Looking forward to getting these on the bench again this weekend, do some testing with and without the jumpers. Removed the jumpers the other day and finally giving them a listen tonight. Haitink's Shostakovich 11 on a Decca recording has amazing stage depth I've never heard before.
Benchmark DAC3 L driving directly into the MinMaxes. 15dB of gain on the MinMax is plenty for the DAC3 to drive direct. I need to change the output jumpers on the DAC3 to get back some useful volume adjustment.
Oooh! A quality, professional DAC. Been thinking about buying it but the price (I am a cheapskate) has put me off.
I wanted something that would last so I paid the big bucks. Most expensive piece of audio gear I've bought off the shelf.
HI I see on my store Papa Acamini pcb that the cap C1 is after R1 ,not as is schematic or your ...you know why ?
tnx
We tested a MinMax on @SRMcGee's Elsinores. Consensus was it didn't command the Elsinores but did control them. Sounded lean on his reference preamp. Auditioned his newly finished B1 Korg Nutube and a B1 Rev2 and the bottom end filled in. Head was bopping the entire time. Forgot to put the pleasenator jumpers back in so no extra harmonics. Had nice placement across the soundstage, not pinpoint but delineated. Depth and space was there, not to the level in my system but I run two MinMaxes in balanced modes with separate PSUs.
Very happy to have these especially given the lower power consumption.
Very happy to have these especially given the lower power consumption.
I do not know why, but I don't think it makes any difference. Try DMing or emailing Nelson Pass?
For additional oomph with a similar sound (and higher power consumption) try the F5m. I'm in the planning stages for a balanced F5m as well for even more fun, but that's for another thread...
My next steps are to try running the bias a bit hotter. Need to do some testing beforehand. Both Scott and I could leave our hands on the heatsinks indefinitely. Need to make sure I'm getting good thermal conductivity into the sinks before I toast something.
After that, considering a linear power supply. Put it in another ACA chassis and stack the output chassis on top. Cute little monoblocks. Maybe do a F5m in an ACA chassis to try.
Adding to the list of things to try, Mark Johnson's AmyAlice SMPS filter is quite effective at removing high frequency switching noise (cheap too!). There is discussion in the ACA Mini thread right now with some saying they prefer an SMPS with AmyAlice over a linear supply.
Thanks Nelson B. I'm going to look into the AmyAlice. These MinMaxes offer more low level detail than the F4s. Very odd, given the straight wire with gain notoriety the F4s have. I was hypothesizing with Scott that it might be due to the F4s having the PSU crammed into a mini-Dissipante chassis with the output stage. Everything is pretty tightly packed, lots of opportunity for stray noise injection. If I get an increase in the soundstage detail, I'll be doubly smitten. My next quest is to get 25Wrms out of a balanced MinMax. Need to look at the heatsink calculations.
-tom
-tom