The NiWatt
Not Your Grandfather’s 300B
The NiWatts continue to amaze people with their ability to drive difficult loads.
If you love the tonal beauty of the 300B tube, but long for more dynamic authority, clarity and rhythmic speed, the NiWatt is your amplifier.
If you are conflicted between the delicacy and beauty of a 45, and the sense of unrestrained power of a 20 watt 845, the NiWatt is your amplifier.
Your grandfather’s 300B was about tonal beauty. The NiWatt pays respect to this aesthetic while building on it.
Old Meets New
To accomplish this, the NiWatt combines a classic circuit, fastidious attention to layout, and an extreme approach to power supply design. The power supply lends a robustness associated with 845s and a clarity we've come to expect from a 45.
Shown at the here is a pre-production prototype. Final construction will be metal as shown in the concept drawing, above.
Grace and Power
Consider the ballerina – an artist/athlete who is a perfect expression of finesse and power – a dancer with precise footwork who is always in time and in perfect balance. A dancer who can bring you to tears.
This is the aesthetic of the NiWatt.
The NiWatt’s calling card is tonal beauty without compromise.
The NiWatt breathes life into your music.
Technical Overview
The Power Supply
Critics of the syrupy sound of most 300B amplifiers are responding to flaws in the power supply design.
By designing a separate (isolated) supply for the output section, the input and driver tubes are freed up from the the harsh demands presented to the output tube.
This contributes to the perception of a dramatic increase in power, because the driver tube is never under stress.
Read about their encounter with a pair of Von Schweikerts. A 300B amplifier should not be able to drive such an inefficient speaker ... and yet the NiWatts do.
It is for this reason that we encourage you to compare the NiWatt with both push-pull 300B amplifiers as well as “transmitting tube” amplifiers like those based on the 845 tube (20 watts). We think you’ll be surprised by the NiWatts' authoritative presentation.
Mirror imaged pairs.
We go to this extra expense in support of implementing the shortest signal path from input jack to speaker terminal.
During development, we iterated through some 50 circuit revisions.
This circuit is so revealing that auditioning various samples of a 3″ length of wire was clearly audible.
"Roadie-Proof" Construction
No expense was spared.
Hybrid, point to point wiring / turret board construction
Ease of maintenance, and immunity to physical shock. This is the same construction method used in guitar amplifiers which are designed to survive abuse from “roadies”.
Parts matter
Every part must justify its place in the NiWatt – from the 3″ length of wire referenced above, to the smallest resistor, and as noted above, the NiWatt is extremely responsive to parts changes.
The most expensive part was not necessarily the best suited to the task. For example, our NOS supply of Black Gate power supply capacitors did not fare as well as power supply capacitors which could easily have been overlooked if one specified parts based on price or reputation.
Of course, there are places in the circuit demanding of premium parts, and it's no surprise that premium transformers justify their place in the NiWatt.
The power transformer, interstage and output transformers are specified from Monolith Magnetics in Belgium. Their output transformer has a bandwidth of 7Hz to 151,000Hz. Yes! You read that correctly.
Circuit Topology
Damper diodes (tubes) are specified in place of conventional rectifiers. Their high current capability conveys rhythmic speed and their reduced switching noise contributes to delicacy and nuance. Refer to the tube section for more details.
Principle #1: when you listen to music through your hi-fi, you are listening “through” your amplifier’s power supply.
Principle #2: with directly heated triodes (because of their low distortion), you are actually hearing your driver tube. This is the key reason for the independent supplies.
Three Stage Design: Input, Driver, and Output
We are firm believers in separate input and driver stages, because the input tube’s job (voltage gain) and driver tube’s job (current delivery) is very different.
Asking a single tube to perform both functions is like asking your BMW to haul a cord of firewood
Input Stage (6SN7): Choke Loaded, RC coupled to the Driver
A classic circuit topology which has withstood the test of time.
We considered direct coupling as well as interstage transformers for this section. Ultimately, we came to appreciate the "tunability" of having one quality capacitor in the signal path.
Driver (6V6): Interstage Coupled to Output Section
This is a perfect spot for an interstage transformer, and the Monolith iron fits the bill perfectly.
Phase inverting (3 gain stages)
An amplification (gain) stage (either a tube or a transistor) inverts phase, so an even number of stages is non-inverting and an odd number inverts phase. Simple, huh?
Ask your manufacturer, because you can’t just count tubes (and it’s really hard to count transistors). Some tubes have dual sections (which may or may not be used), and other tubes may not perform amplification functions (i.e. cathode follower).
Tube Compliment
Rectification - 4 damper diodes (6AU4)
Traditional rectifiers (5AR4, 5U4G, etc.) are dual diodes (two diodes inside one tube). Damper diodes have a single diode, so replacing a 5AR4 requires two damper diodes.
One diode pair provides high voltage to the 300B & the second pair supplies the input and driver section.
Signal tubes
- 1 6SN7 (input tube)
- 1 6V6 in triode mode (driver tube)
- 1 300B (output tube)
The musical benefit of damper diodes
Most individuals are unfamiliar with damper diodes. They have much lower switching noise. This translates into a less “hashy” sound than even the best new old stock rectifiers.
They also have much higher current capabilities than normal rectifiers. All things being equal, damper diodes follow musical transitions with more finesse and speed.
Damper diodes in plentiful supply in new old stock, and as an added bonus, they are priced lower than what you’d pay for current production 5AR4’s from Sovtek, JJ etc.
How does it get better than that?
Pricing
Introductory pricing: $17,995
Please refer to our COVID statement for current updates on travel and customer interaction.
Yes, COVID has delayed the official NiWatt launch, but we’ll build you a pair at this introductory price.
Price includes:
A $500 travel rebate:
If you visit Galibier to audition and purchase a NiWatt within one year of your visit. Visit Colorful Colorado on our dime!
Free Power and Speaker Cables:
NiWatts are delivered with two Wind River Power Cables and a single-wire set of our Wind River Speaker Cables.
If you have already purchased any Wind River Galibier cables in the past, we’ll credit you for the price you paid for any three cables. Credit is for the price paid, less tax and shipping.
Cable notes:
These cables are not “throw-ins”. They were instrumental in the prototyping and development of the NiWatts. We needed better tools, so we had to design them.