I have upgraded the capacitor/resistor with 9-22uF Mudorf Supreme capacitors and a 1.5 ohm Duelund resistor on each 2905 speaker.
Here are my impressions at 100 hours:
Much more coherent, space around instruments sounds more "right". Timbres and brustling sounds from musical instruments are less smeared/obscured. For instance I can now hear Stan Getz taking breaths between notes on "Getz/Gilberto". Glare is reduced to the extent that some recordings which were bordering on unlistenable are back on my playlist. The 60 Hz bump in the low end has been tamed. My big concern that the highs would get edgy or sterile did not happen. Overall changes to the frequency response I would characterize as a slightly less warm/heavy balance which I prefer. The midbass is less round and smeared so a lot of new information is heard in this range. Textures in the mid to upper bass are easily discerned and transients on drums and piano are much more realistic. The low frequency rolloff seems to be about the same but I will probably still try an additional 22uF to evaluate the effects. I also going to try a 4.7uF Mundorf silver/oil on the capacitor bank and will report back on bypassing with other capacitors. Possible suggestions would be appreciated. I will probably also try a 1.35 ohm resistor.
I did make one disturbing discovery during the upgrade. One stock capacitor tested at 216uF and the other was 255uF. This would partly explain why there was such a big improvement in imaging and bass resolution. Both resistors measured 1.6 Ohms. Concerning the cost, I purchased the caps and resistor with a nice 20 percent discount that Partsconnexion was offering, so $1300 was a lot easier to swallow. Would I do it again? At this point, it's a no brainer especially considering how badly matched the stock caps were. I'd say, on the major characteristics I hoped to improve, all were easily met with the exception of the leaner bass which I would rate a draw although its seems to be improving every day with further break-in.
I appreciate all the information from other agon members. I will issue an update after the break-in is complete.
Here are my impressions at 100 hours:
Much more coherent, space around instruments sounds more "right". Timbres and brustling sounds from musical instruments are less smeared/obscured. For instance I can now hear Stan Getz taking breaths between notes on "Getz/Gilberto". Glare is reduced to the extent that some recordings which were bordering on unlistenable are back on my playlist. The 60 Hz bump in the low end has been tamed. My big concern that the highs would get edgy or sterile did not happen. Overall changes to the frequency response I would characterize as a slightly less warm/heavy balance which I prefer. The midbass is less round and smeared so a lot of new information is heard in this range. Textures in the mid to upper bass are easily discerned and transients on drums and piano are much more realistic. The low frequency rolloff seems to be about the same but I will probably still try an additional 22uF to evaluate the effects. I also going to try a 4.7uF Mundorf silver/oil on the capacitor bank and will report back on bypassing with other capacitors. Possible suggestions would be appreciated. I will probably also try a 1.35 ohm resistor.
I did make one disturbing discovery during the upgrade. One stock capacitor tested at 216uF and the other was 255uF. This would partly explain why there was such a big improvement in imaging and bass resolution. Both resistors measured 1.6 Ohms. Concerning the cost, I purchased the caps and resistor with a nice 20 percent discount that Partsconnexion was offering, so $1300 was a lot easier to swallow. Would I do it again? At this point, it's a no brainer especially considering how badly matched the stock caps were. I'd say, on the major characteristics I hoped to improve, all were easily met with the exception of the leaner bass which I would rate a draw although its seems to be improving every day with further break-in.
I appreciate all the information from other agon members. I will issue an update after the break-in is complete.