Just wanted to share with everyone the results of my experiments on using Tube Speaker Amp to drive Headphones. Here goes
1. Bought 2 units of ART Headtap - why 2 - wait ....
2. Load matching 10 Watt 10 ohm resistors.
3. 1/4 inch phone jacks - No TRS - Not stereo 4 pcs
4. 1 piece Female 4 pin XLR connector
4. Wires 16 ga gold plated OCC wire.
Amp - Audiopax Stereo 88 power amp - KT88 1 per channel, 12Ax7 driver 1 each channel. 15 watt RMS 8 ohm/4ohm
Output impedance 3.7 ohm
I drive the Amp with my Ibass Dx100 - Hdp R-10 (Japanese version)optical to the Centrance Hifi M8 than 1/4 inch to RCA to Amp Rca Input
For the Power Amp as follows:
Load each speaker terminals in parallel with the 10 watt , 10 ohm resistor - Still trying to upgrade to Vishay non-inductive. Meanwhile found suitable power resistor on Ebay. Big cement covered 10Watt resistors.
Rigged up (DIY)) Banana Plugs - 16ga OCC gold wire to 1/4 inch phone jack to Input of ART Headtap - 1 per channel. ( you need 2 Headtap)
Rigged up (DIY) 1/4 inch phone jack - 1 per channel to a Female 4 pin XLR - then I plug in my Sennheiser HD800 with a balanced 4 pin XLR plug
Volume can be adjusted with HDP R10 or M8 My Latest expt. listening to my HD800 as I type this- HDP R10 Can also drive the Power amp on its own directly.!!!
I have experimented step by step so as not to take a risk and blow up my HD800 by using disposable Earbuds,B. Every step I was careful.
Even tried 1 ART HEADTAP in stereo mode with a wire rig Left and RIght speaker output of Power AMp to 1/4 inch TRS - ie. Negative terminal of L and R channel joined Common to Sleeve of 1/4 inch TRS plug
Nothing Blew up - BUT NO SOUND - Whole Amp sound got earthed. But your amp may blow up. Mine just DID NOT
Went back to 2 ART Headtap - Slowly set volume to Zero and slowly adjusted everything step by step Up in volume
SQ - A bit of grain or tube rush in the background. - I prefer the tube smoothness to Solid State and Op Amp sound in my opinion. HD800 never sounded richer in the mid bass!
Disclaimer - The above is MY PERSONAL Experience. If you do try anything on your own, it is entirely at our own risk and choice. Tube Amps are High Voltage and HOT HOT.
I am not responsible for anyone's effort or trials. The above is my tests on my OWN equipment at MY OWN RISK ENTIRELY.