Projects, rebuilds and or modifications….

from last year modding the caps and now the resistors of my super cheap chinese 6p1 amp

initially i used an adapter to use 6aq5s in place of the 6p1. brimar, great change.

also mullard ef95s, would the sound be too cuddly? not if you clean the tube pins well, what a revelation. mullards and brimars sounding transparent pristine, who would ve thought it?

i also found that NOS paper oil caps (US and USSR) as good as or better than modern commercial types like rike and mundorf.

at far lower prices. far lower.

I’ve been in the middle of designing a fully remote, all-discrete integrated amp going on 3 years now :-) So many details o work out, mostly from scratch. switching, switching logic, display logic, EMI immunity, gain stage, RIAA stages with 1500X amplification (can you say "low noise critical?") headphone amps, thermal control, DC sensing and shutdown, discrete volume and balance, human factors, ...... And once something is done, i learn how to improve it. Getting very close to the DFM stage tho, once i fix a few dozen lines of logic control code and refine the active ripple rejection i’m testing out (emphatically not a regulator)

The learning is a ton of fun, and as noted above, the pattern learning of "what makes what difference, and what, surprisingly, makes no difference or harms the perceived sound" (last one is rare, whew)

It has also forced me to go back and do far more extensive benchmarking of my older designs so that i have a reference for improvement. Sometimes that is a flattering experience such as when i measured, under roughly half load, my output stage power supply from 25 years ago, employing tube type PS design to a solid state amp, and measured less than 8mV ripple on the rails. i Concluded that using that product as my test mule was pointless since i was approaching the limits of field measurement. for the non nerds 1mV = 1/1000 volt (rms in this case). In a smaller, vastly cheaper product however the ripple rejection circuitry will yield great benefits. Now to prove/confirm it soudns the part.

The school of hard knocks, my father used to say he had a masters from the university of hard knocks. Hadn’t heard that in years.

Another one I’m trying to workaround is the VPI Periphery Ring. My main table has an 11 1/2” platter that I’m quite happy with. Unfortunately the ring requires a 12” platter. Found some 1/4” o-ring material. Going to try to make a ring spacer for the periphery ring. 

“The biggest joy I get from modding is the steps of improvement and the sq improvements you can achieve with the proper mix and there are many sideway moves and a few set backs.”

Agreed. Regardless of the modifications being a win or a loss, it is knowledge acquired. The school of hard knocks, if you will. 

barrysandy there’s a guy on WBF who,s done a beautiful job on his ref 40 the same resistor upgrade along with extensive more mods, look it up its worth a look up to see the extent he has gone with many photos of his journey.

A couple months ago I replaced the g luxman electrolytic caps with Nichicon FW and resistor with a Audio Note 1/2 w and the ac inlet with furutech ncf in two W4S LPS powering the router and fmc the second powering fmc and aqvox switch.

Clean power is a Must in the digital area with usually minimum expense and the greatest amount of sound improvements.

The biggest joy I get from modding is the steps of improvement and the sq improvements you can achieve with the proper mix and there are many sideway moves and a few set backs.

Replacing anywhere from 16-24 stock resistors in the signal paths of each of my ARC REF 40 preamp and REF 10 Phono with Vishay Z-foil/TX2575s. Mucho improvement, but trying to figure out the right number and positions for best results. Still fiddling with it.

Also will be playing with a pair of TUBULUS Argentus DB-25 cables on my Pass Labs XVR-1-3 way crossover. This unit was modified some time ago during a 2 year period with ~130 parts replacements in 30 different listening trials. I’m never doing that again thank God...!

Several in the works, currently working on a pair of Yamaha B3's.

I’m in the middle of rebuilding and modding my shunyata ps8 , so far I have installed 5 Rifa X2 Y2 Y2 caps with the leads replaces with mundorf silver gold wire, replaced the inlet with furutech NCF , internal 12 g wire replaced with furutech 10 g from an unused sp55 n , installed 2 furutech gtx r ncf inlets, a couple of dueland silver bypass caps, a couple of v cap cutf caps  and it’s sounding pretty GD considering al these parts were extras laying around “ it may not be an Everest but it’s pretty impressive.

Once these settle all put a couple more ncf inlets and a few more duelands in.

SG200 being converted to battery power, with upgraded amplifier stage with more gain.

Working on adding active shielding.

Plus another one for the SG, but unfortunately that one is classified K.