In exclusive partnership with top-tier modification house Cullen Circuits, Underwood HiFi is proud to offer the following carefully tested performance enhancement packages for the Xindak XA-6950 integrated amplifier.


We are now offering a Level-1 and Level-2 modifications for the Xindak XA-6950 integrated amplifier. The stock XA-6950 is a fine $1500 100wpc integrated amp that runs the first 30 watts in class A. The 6950 uses parts far above its price. The output stage utilizes three pairs of audiophile-grade high-current Sanken transistors. Consistent with all Xindak products, only audiophile-grade components found their way into the XA6950. The amp uses Dale resisters from the USA, Wima MKP capacitors from Germany, Gotham wiring from Switzerland, to name a few. One of the RCA unbalanced inputs uses an American-made CMC 24K gold-plated connector for the most critical listening.

The mods were designed and are performed by Rick Cullen at Cullen Circuits in California.
Our Level-1 mod [$650 + frt retrofit, $1.690 + frt preinstalled] adds 52 Dale resistors in the most important signal path areas. We also upgrade 14 capacitors to Nichycon's. This is a 4.5 hour mod.

The Level-2 [$1.300 + frt retrofit, $2.190 + frt preinstalled, intro price $1.900 + frt] goes all the way and replaces all 142 resistors in the signal path and upgrades a total of 50 capacitors. This is a 7 hour mod.
Improvements in both mods are as follows. The L-2 gets an additional 40% improvement over the Level-1:
  • We make a major improvement to the midrange. It is more liquid and tube-like. The modified amp is now able to compete with the better $4000-$5000 solid-state amps. This was the major design goal of the mod and we think that we have accomplished the task.
  • The amp is quieter, silences are blacker. It thus resolves more low level detail, has better ambiance retrieval and is much more three-dimensional.
  • Bass response is improved big time. Both bass extension and mid-bass slam are affected.
  • Imaging is more focused while the entire soundstage is both deeper and wider.
  • Transparency is dramatically improved. You get a much cleaner look into the musical soundstage.
  • Dynamics are dramatically improved. It's as though the modified amp gains power. The stock unit is rated at 100 watts. Once modified, it sounds like a few dB of additional headroom. The stock unit's real forte is its detail and dynamics. Our mod makes it far better from bass to treble. The Level-2 adds better dynamics and has much better pace as well as a good increase in transparency. It seems to play much louder on peaks. There is a lot more excitement in the music. It now just sounds more powerful with far better control.
  • Treble detail, both micro and macro, is improved and now keeps up with amps selling for up to $4,000.

Click the Next Arrows to return to the ModPage.
Or click on our e-mail below to ask further questions.