Single-ended DHT Super OTL Power Amps

Model no: SE-300B-845-100W-DELUX

Expected retailer / reseller on-sale price $28,000 and up

No-frills direct-out-of-our-factory price C$13,800 Untitled Document [US$ 11040] !!

100Wrms x 2  single-ended DHT pure class A triode Super OTL power amplifier with true balanced inputs.

This is our high power series of single-ended DHT Super OTL power amplifiers which use the 300B / 2A3 , and drive the 845 or 211 tubes. Input tubes can use 6SL7, 6SN7, 6SU7 , 5691, 5692, ECC32, ECC33, ECC35 and all equivalents.

This model has both RCA and XLR inputs, power-on delay and speaker DC offset protection circuit included for maximum safety consideration.

This amp features the following mind-blowing characters:

1. 0db NFB from input to output , all tubes working in pure class A single-ended operation mode, as well as point-to-point hand wiring technique.

2. Pure analog linear power supply and amplification design for lowest possible un-pleasant distortions, result in much better sonic performance than those others who use switching power supply or class D amplification.

3. Our proprietary Super OTL design without output transformers, maximum damping factor and most widest bandwidth can be achieved, the beautiful characters of the 300B/2A3 + 845/211 is totally exposed, the bass punch, control and richness is so good that exceeds any old school 300B+845 designs while the mid and high range silky outstanding dynamics as well as sweetness still holds. Just one single 845 as output tube, no need to parallel two or more tubes, results in the most purest and linear class A sound.

4. Super low noise level, you can hardly hear such quiet and dark background from an old school 845 / 211 design

5. Automatic pure class A biasing, not necessary to re-calibrate but just plug and play of different tubes. All the tubes work under totally safe and long lasting operation conditions, which can almost last forever until the filament drops dead.

6. High current power supply guarantees superb bass control and sonic performance.

7. Integrated our most advanced MDE (micro-dynamics extraction) design. Which can let very minute information originally immersed below background noise surface out effortlessly. You can easily hear the real end of each music note in the recording which you never experienced before, with those invisible links between each note. Every musical instrument will have astonishing 3D separation from each other but with the invisible musical link in between. Any musician can get really excited by the performance of this circuit, since each phrase of notes and chords can easily tell without being masked by vocals or other instruments, a real musical reproduction of sound.

8. Two separate power transformers (power stage, tube stage and filament transformers) for lowest interference between supplies and highest dynamics with stressless sound.

9. Real out-of-the-factory price, no expensive marketing and reviews which cost typical 80% or more of the unit price. Your one dollar investment gets at least 5 to 10 dollars back in terms of sound.

10. Soft start filament supply to all the tubes for prolonged life time.

11.274B organic tube rectifier offers the most open and airy organic sound, 3D holographics sound stage. This is one of the best sounding amplifiers offered by us, extreme crystal transparent with high texture high density sound, there is no hollow spots in the whole sonic picture, all filled up by music with ultimate musicality and dynamics.

12. Constant current amplification design to achieve the lowest noise level and highest linear gain from tubes, high gain with variable gain control, which can match any speaker or pre-amps easily.

13. Dual vintage look power output meter for monitor purpose.

14. Soft start and speaker protection circuit built-in to protect your speakers.

15. 100% professionally hand-built in Canada by component-to-component and point-to-point wiring technique 

16. Full loaded and fully upgrade with carbon resistors, oil capacitors, WE wire, enhanced power transformer and filter capacitors.

17. XLR and 1/4" headphone output which can power any headphone to reasonable loudness


No. of inputs 1 set of RCA inputs + 1 set of XLR balanced inputs (input impedance 100Kohm typ)
No. of outputs 1 set of speaker outputs ( 4-16 ohm)
Freq response 5Hz - 28Khz (-3db)
S/N > 90db at full power output
Phase non-inverted
manufacturing hand-wired point to point for tube and power supply sections
Tubes used 6SL7 / 6SN7 / 6SU7 x 2 + 300B / 2A3 x 2 + 274B/5U4G x 1+ 845 / 211 x 2
Output power per channel

100Wrms (8 ohm)

Adjustable gain setting

max. 200Wpk (4 ohm)

1 year parts and labor warranty, tubes 90 days under normal operation condition


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