Last Critical Tweak… how to quell occasional high harshness…?

Perhaps the simplest and most effective thing would be to add Duelund 0.01uf bypass cap to those Mundorfs. You could be quite surprised by how such a little tweak can alter voicing in such a profound way. In my case needed a bit more air, spaciousness on top, went with the Duelund silver bypass cap, wonderful add! Read the many reviews on these. As for Duelund general house sound, natural, effortless sound quality are in the substantial majority of reviews, and this my experience with a their caps, resistors, wire over many years. Negative reviews are outliers, some other issue in those setups, one can likely find negative reviews on virtually every audio product ever produced. 

 

The Cardas Clear IC while a very nice cable isn't going to solve this issue, in fact it could exacerbate the issue being a more resolving cable than Duelund.

Hello all,

 

I’ve taken a few moves and have some updates. 

 

My test track for this diagnosis is the lovely and melloncoly: 

Confronting Inertia by John Adler. The horn peaks at: 2:46, 3:50, 4:40, 5:27, 

 

Responses to many of your questions / comments: 

-Power cords are all stock, on a decent power strip designed for audio gear I bought years ago

-Speaker placement has been fine tuned to work well, i don’t think this is an issue

-Room Treatment I have yet to take on, but I hear from many other Open Baffle and Pure Audio Project owners that they actually removed room treatment to better effect with these speakers. Open Baffle seems to use the room to some degree. 

 

SO…. I have been tweaking in an attempt to track down the high frequency shrill I describe, and hear in spades in the above mentioned John Adler piece. I have tried:

 

-Tube swaps. The Mullard’s on the main gain position (both NOS and new) have the shrill. When I put the Brimars in the main gain the shrill disappears to about 10%, but I loose all the joy of the mids from the Mullards… this is not a preferred solution. 

-New RCA: I recently obtained the Silversmith RCA Interconnects. It’s gorgeous and wonderful and musical. The Shrill is reduced slightly, to about 80%. 

-Old RCA: When I swap out my old Encore II RCA, the shrill mostly disappears. The sound  overall is muted and so this route is not preferred in general. 

-Duelund RCA 16GA, on the Frybaby for extra long: High Harshness is very very present!

 

I am thinking the Duelund 16 speaker cables and internal wiring is the source of the remaining high frequency shrill… in my system… 

 

And for that, I am thinking, based on a review of other Pure Audio Project owners, trying  internal wiring of AntiCables (which version?) and then perhaps a speaker wire change from Duelund….

 

Does that sound right? 

 

I would love to upgrade the power throughout but that sounds to be way out of my current budget… (10K for amp, streamer, dac…?) What is the first affordable bang for buck first step to addressing power? 

The crossover modifications (yes I already upgraded the Cap to Mundorf silver/gold oil, as per PAP’s recommendations…) are interesting, and will consider if all else fails. 

Thank you all for your insights and suggestions. 

Onwards to audio bliss! 

 

R. 

I am confused by the Old RCA comment, didn’t you replace them with the silversmiths with positive results?

Start with speaker cables before changing your speaker wiring. If you like the Silversmith interconnects, maybe try their speaker cables. 

I spent the day trying to diagnose the shrill, trying all sorts of things with the high pass filter, triad mode vs ultra linear…. I had distortion seemingly creep up in my left channel, which had me switching the tubes, the interconnects, and finally the speaker wire, from Left to Right. Only the speaker wire change changed the distortion from my left horn to my right horn. 

 

? 

 

I on a whim decided to swap out my Gold Lion KT 77 power tubes for my previous set, Tung Sol KT 120. And I think all the shrill is mostly tamed now. 

 

WTF??? 

Were my Gold Lion KT77’s slowly loosing their ability to do higher frequencies? 

Listening now to the Tung Sol KT 120’s, I am relieved… but I miss the qualities of the Gold Lion’s. I couldn’t stand the sense of mid range bloat to the Tung Sol’s, so I put the Gold Lions back in… the distortion seemed there for a track and then subsides… 

It’s a little frustrating. As my set of Gold Lion KT77’s are less than a year old. 

Do I find a new set of better Power Tubes? 

Endless…

 

r.