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FS: Tubelab SE II 45 Headphone Amp (speaker amp option)

itsikhefez

Member
Paid Member
2015-08-24 2:28 pm
For sale is a Tubelab SE-II 45 headphone amp with volume control (conversion to speaker amp possible, see below).
I recently finished another TSE and have way too many amps and projects so looking to move this one along.

This TSE has been optimized for headphones ranging from 40ohm to 300 ohms (and likely 600 but not tested).
ElectraPrint 5K:32 with 250ohm load resistors to present a more ideal load to the 45 (and to avoid accidental use without headphones connected).

PARTS SELECTION:
- ISO Japan power transformer for extremely quiet, buzz free operation. (I tried Hammond 370EX & 370HX before and the mechanical noise was too loud)
- ElectraPrint 5K:32 output transformers
- Neurochrome 21st Centry Maida HV Regulator for ultra-low PS ripple. This was essential to get hum free operation. Standard CLC and even CLCRC had audible hum with Senn HD650, 103db sensitive headphones.
- DACT CT2 20K stepped attenuator
- AudioCap PCU Copper Film & Foil 0.1uF coupling caps
- WBT-0210 CuMs Topline Nextgen RCA sockets
- Audio Note Nickel Plated 4-pin sockets
- Takman REY and TKD metal-film resistors
- Test sockets on rear panel for setting 45 bias. Pre-drilled holes for 5842 test sockets.
- CNC-milled chassis from Landfall Systems
- Kimber TCSS and Mogami coax wiring

Chassis dimensions: 15.5 (W) x 11.75 (D) x 3.25 (H)
B+ set to 285V on HV regulator.
Biased at 32mA, I measured about 1W, 3% THD to 33ohm and 250mW, 0.95% THD to 300ohm.
If you remove the load resistors, you can squeeze out 1.7W, 3.5% to 33ohm, and 283mw, 0.7% THD to 300ohm.

In this configuration, parts alone would cost atleast $1650. I spent over $2K along the way due to components not be sufficiently quiet for a headphone amp (such as hammond transformers, choke, ASC PS caps etc)

I am asking $1450 including a full tube set: National Union 45's (matched), Amperex Gold Pin 5842 and Sovtek 5AR4 (easily worth over $100)

SPEAKER AMP CONVERSION OPTION:
- If you would like a 45 speaker amp, I can remove the ElectraPrint OPTs and you can fit in any other 5K:8 ohm OPT in it's place. In this case, I will include a new blank front panel and deduct $200 from price. You will have to drill holes for speaker binding posts in the rear or side.
- If you don't need volume control, I can remove the the DACT and wire the RCA directly. In this case, deduct $150 from price.

Other notes:
- The PT is not compatible with 2A3, but with minor modifications this can be converted to use 300B's. That said, the B+ would be rather low.

Thanks for looking, feel free to ask any questions!
 

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