Another low cost DIY tube buffer kit (***Update#2***)

Bought a different version of the low cost DIY tube buffer kit to try.

The new toy uses two  Chinese 6J3 tubes, with option of US made 5654W(s). My initial purchase was with the default Chinese made 6J3.

The main PRO for this 2nd DIY set is more space around the capacitors in the audio critical path eg the yellow poly(s), permitting a much larger variety of potential substitution choices.

Initial kit purchased

Similar layout to the previous kit but with more space for swapping the critical capacitors

Uses non-mainstream EC capacitors on the PCB

The default 6J3 purchased with the kit

Assembled kit in-action 

This new kit has the same power requirements and input-output layout(s). However, the output volume for the new kit is much lower than the previous. The potentiometer output is even at low volumes and cames with a volume knob which also functions as a power-on/off switch. To enable more space on roughly the same footprint, the new kit uses SMD resistors which were pre-soldered onto the PCB.

How does it sound?

Best way to describe is as if someone enabled a "tonal normaliser" on the output😬.

When I contacted the seller, they assured using the US made 5654W would make a "night & day" difference. Many online reviews does mention the US made 5654W(s) are worth the upgrade. Thus I placed an order for a pair since these did not cost an arm or leg!

Will update next month once I received the 5654W(s) and give them a spin.

1Nov2019

6J3 (LHS) vs 5654W (RHS)

Been using the buffer kit with the newly installed 5654W(s) for past few days and can confirm they do produce a remarkable improvement over the 6J3(s). Received the 5654W(s) quite a bit later than usual and suspect that is due to the decrease in the number of shipments from PRC with the on-going trade-war between the two big economies. 

Thus did not have the opportunity to run-in the 5654W(s) properly before this update. At the moment I can safely say that the "tonal normalisation" has been removed. The DIY kit is beginning to sound like a proper tube component.

Will allow the 5654W(s) to settle in before deciding if to start substituting the capacitors in the critical path.

Late September 2022

Pix after "upgrade"

Was considering changing the default yellow 1uF as the sonic reproduction was pretty good but could be better.

Hence did not wish to waste proper quality capacitors for a "Proof-Of-Concept" evaluation.

Found a few of the 2.2uF poly(s) which was removed from other units, since it has long leads, was suitable as a candidate#1.

Will leave it for the moment for further listening, and, swap out with others for further evaluation.

To be update iagain n the future.