If the HK receiver has pre-outs AND power-ins and these two can be disconnected, you could use a tube pre-amp and connect the R&L outputs of the pre-amp to the R&L power-ins of the receiver. This would be the desired setup you seek, but I don't know if the HK has power-ins. Also, I don't know if the incremental benefit would be cost effective.
If your system is 2-channel only, I would suggest waiting until you can afford a quality integrated amp and replacing the receiver altogether. If you want to continue to use the tuner from the HK, just connect the pre-outs or tape out to the new integrated amp.
BTW, I have owned the Cayin TA-30 in both stock and fully BizzyBee mod'd styles. It is very good for the price!
Enjoy,
TIC
If your system is 2-channel only, I would suggest waiting until you can afford a quality integrated amp and replacing the receiver altogether. If you want to continue to use the tuner from the HK, just connect the pre-outs or tape out to the new integrated amp.
BTW, I have owned the Cayin TA-30 in both stock and fully BizzyBee mod'd styles. It is very good for the price!
Enjoy,
TIC