【Voltage Compatibility】
When using electrical appliances, please note that they are designed for Japanese voltage specifications (90-110V), so if you use them with a different voltage, it may cause a malfunction.
【Plug Type】
Our products use Japanese plug types (A or B type).
Please use a conversion adapter if necessary.
【Important Note on Transformers and Adapters】
A transformer adjusts voltage to match your device’s requirements.
A conversion adapter only changes the plug shape and does not adjust voltage.
Using only a conversion adapter without a transformer may result in damage to the product.
【Liability】
We are not responsible for malfunctions or damages caused by improper use, such as operating the product without a transformer.
soldering assembly kit
[Compatible vacuum tubes] *Please prepare one voltage amplification tube and two output tubes separately. ・Voltage amplification tube: 12AX7 (ECC83, 7025) ・Output tube: [LOW mode] 6V6 series, 6F6 series, etc. [HIGH mode] 6L6 series, EL34(6CA7), 5881, 7581, WE350B, KT66, KT77, KT88, KT90, etc. *KT120, KT150, KT170, etc. can also be used, although the safety cover cannot be attached.
[Circuit configuration, etc.] ・Output stage Class A single, active auto bias (low loss auto bias) ・Heater lighting method Voltage amplification tube: AC lighting ・B power supply MOSFET ripple filter (left and right independent) ・Preamplifier function INPUT-2 has a preamplifier function using an operational amplifier (NJM2068DD is included)
[Mode switching] [Power mode] LOW, HIGH [Output tube connection mode] UL (ultra linear connection), TRIODE (triode connection), PENTODE (pentode connection)
[Maximum output] [HIGH mode] 2 x 7W (6L6), 2 x 8W (EL34), 2 x 8.6W (KT88), 2 x 9.8W (KT170) [LOW mode] 2 x 3.3W (6V6), 2 x 2.6W (6F6) (8Ω, THD10%, in UL mode)
[Rated input] INPUT-1: 850mV rms (at HIGH mode, UL, EL34) INPUT-2: 225mV rms (preamplifier function gain 11.5dB)
[Frequency characteristics] 20 to 50,000Hz (-3dB, UL, HIGH mode)
[Power supply voltage] 100V AC (50/60Hz) IEC standard 3P inlet type [Rated power consumption] 80W (HIGH mode, when using KT170), 71W (HIGH mode, when using EL34), 36W (LOW mode, when using 6V6)
[Input terminal] INPUT-1: RCA jack stereo 1 system INPUT-2: 3-pole mini (Φ3.5mm) jack (with preamplifier function by operational amplifier) [Output terminal] Binding terminal (gold-plated specification, banana plug can be used) Headphone output: 3-pole standard (Φ6.3mm) jack
[Body dimensions] W252 x H189 x D286 mm (When safety cover is attached, including protrusions) [Body weight] Approximately 6.6kg (When completed, excluding vacuum tubes and power cord)
The TU-8400 has an "active auto bias function" inherited from the TU-8200R and two power modes, HIGH and LOW. In the HIGH mode, the 6L6 series, KT66, KT88, KT90, EL34 (6CA7), 5881, 6550, etc., and the heater winding of the power transformer. Since the wire has a margin, it is also possible to use KT120, KT150, and KT170. You can also use 6V6 and 6F6 by switching to LOW mode. *Vacuum tubes are not included in the kit.