Article · Published 2026-10-29
Demograf Atlas and Western Electric 91E compared: two 300B amplifiers for loudspeakers and headphones
Two single-ended 300B integrated amplifiers can look alike on a spec sheet and still be built for different listeners. This guide puts the Demograf Atlas next to the Western Electric 91E, both class A single-ended amplifiers on the 300B triode that can drive loudspeakers and headphones. It sets out power, outputs, size, price and what each maker includes, using the makers' own published data, and then suggests how to decide. It does not rate the sound of either: we have not measured or listened to the 91E, and numbers on a data sheet do not settle how an amplifier sounds in your room.
Atlas and the 91E in short
- Power. Atlas is rated at 5 W per channel at 8 Ω; the 91E at 2 × 20 W (10 % distortion). The makers do not state the figures on the same basis, so compare the order of magnitude rather than the digits.
- Headphones. Atlas has a 6.3 mm and a 4-pin XLR output as standard, and other connectors on request. The 91E page lists a headphone output without naming the connector.
- Extras. The 91E adds a phono stage, Bluetooth, a remote control and six inputs. The Atlas specification lists none of these: it is a line-level amplifier with a ground-lift switch.
- Price. The 91E is listed at $7,999 (Nickel $8,499) factory direct. Atlas is made to order from about $24,800. The difference is real, and the sections below say what each price covers.
Specifications side by side
| Demograf Atlas | Western Electric 91E | |
|---|---|---|
| Circuit | Single-ended, pure class A, integrated | Single-ended, class A, integrated, steered current source |
| Output tubes | 2 × 300B | One matched pair of Western Electric 300B |
| Other tubes | 2 × 6Zh4 (other types optional); rectifier 2 × 6D22S or 1 × 5C3S | 2 × ECC81 |
| Rated output | 5 W per channel at 8 Ω; push-pull version with double power on request | 2 × 20 W at 10 % distortion; 2 × 16 W at 5 %; 2 × 14 W at 3 % (4 Ω and 8 Ω) |
| Loudspeaker impedance | 8 Ω; 4 Ω or 16 Ω on request | 8 Ω block fitted; 4 Ω or 16 Ω block optional |
| Inputs | Analogue RCA (balanced XLR on request) | Six audio inputs, phono MM/MC, Bluetooth |
| Headphone outputs | 6.3 mm and 4-pin XLR; 2.5, 3.5, 4.4 mm, dual 3-pin XLR or electrostatic connector on request | One headphone output (connector not stated on the page) |
| Volume control | ALPS potentiometer (stepped attenuator optional) | Stepped resistor attenuator, remote control |
| Mains | 100, 120 or 230 V, set at order time | 100, 115 or 230 V |
| Weight and size | From 45 kg; from 450 × 450 × 250 mm | 22.2 kg; 480 × 380 × 280 mm |
| Warranty | One year (extra +1 or +2 years) | 90 days, extendable to three years after registration |
| Price | From about $24,800, made to order | $7,999 (Champagne, Black), $8,499 (Nickel), factory direct |
| Made in | Kazakhstan, by Dmitriy Gubchenko | USA |
Western Electric 91E data from the maker's page, westernelectric.com/91e, read on 29 October 2026; Atlas data from our model page and the price list of 27 October 2026 (the model page shows the current price). We have not measured or listened to the 91E. Western Electric is a trademark of its owner, with which we are not affiliated.
Five watts or twenty?
Output power is the biggest difference on paper, and what it means depends on your loudspeakers. A single-ended triode amplifier delivers its first watts very gently and then runs out of headroom; the loudspeaker's sensitivity decides how loud “out of headroom” is. A loudspeaker rated 95 dB at 1 W and 1 m, such as our Cassandra, reaches comfortable levels in a normal room on a few watts, and a 103 dB model such as Orpheus needs far less. A loudspeaker near 87 dB needs several times the power for the same level, and there 20 W gives real room. Our guide to loudspeakers for single-ended amplifiers has the sensitivity-by-power table. If you need more than five watts and prefer an Atlas, it can be built push-pull for double the power; single-ended or push-pull explains the trade-off.
Headphones
Both amplifiers are described by their makers as able to drive headphones. On Atlas the connectors are part of the order: 6.3 mm and 4-pin XLR as standard, and 2.5 mm, 3.5 mm, 4.4 mm, dual 3-pin XLR or an electrostatic output on request, so you name the connector of the headphones you own. For the 91E the page does not say which connector is fitted; if your headphones use a balanced or small connector, ask Western Electric before you order. In both cases check the headphones' impedance and sensitivity against the amplifier's output, which matters more than the label “300B”.
What else is in the box
The 91E is a complete system hub: a phono stage for a turntable, Bluetooth, six inputs, a remote control and an automatic bias circuit for the 300B pair. If you want one box that plays records and streams from a phone, that is a clear point of difference. Atlas has a narrower brief: line-level sources into a point-to-point wired single-ended chain, with the ground-lift switch for hum. If you use a separate phono stage and a digital source with its own volume control, the extras do not cost you anything you would use; if you do not, they do.
Price, and what it covers
The 91E is a production model made in the United States and sold factory direct at $7,999 to $8,499, with options priced separately. Atlas is built to order, one at a time, in Kazakhstan: the lead time is 6 months or longer and a 50 % deposit reserves your place in the queue, with the balance due after the measurement report of your unit, before shipping. Shipping and insurance are paid by the buyer and shown as a separate line in your quotation. Parts that account for a large share of the price of any made-to-order tube amplifier, such as the output transformers, the power supply and hand wiring, are described in what a tube amplifier costs and what you are paying for. A higher price is not an argument about sound; it is a list of what was paid for, and you can weigh it against what you need.
How to decide
- Start with the loudspeakers. Note their sensitivity and impedance and the room size; from that, decide whether 5 W is enough or you need 20 W (or a push-pull Atlas).
- List the sources. Turntable, streamer, DAC, phone: do you need a phono stage and Bluetooth built in?
- Check the headphone connector. Name it and make sure it is offered.
- Decide how you want to buy. Off the shelf and quickly, or built to your specification over six months or more.
- Check the mains. Atlas is built for 100, 120 or 230 V at order time; confirm the voltage and plug for your country with either maker.
- Look at service and warranty. One year (extendable) against 90 days (extendable to three years after registration) means different terms; read both.
Questions
Is five watts enough for a 300B amplifier?
For efficient loudspeakers, yes: with 95 dB or more at 1 W, a few watts of single-ended class A reach comfortable levels in a normal room. For loudspeakers near 85 to 88 dB, usually not, and a higher-power or push-pull design is the sensible route.
Why does a made-to-order amplifier cost several times more?
Because the same parts are made one unit at a time: custom-wound transformers, selected tubes, hand wiring and individual measurement are paid for per unit. The guide on tube amplifier prices lists the components.
Can the Atlas be ordered for my mains and headphones?
Yes. Mains voltage (100, 120 or 230 V) and the headphone connectors are fixed in the quotation. Write to us with the loudspeakers and headphones you use, and we will propose a configuration. Prices and terms on the model page are current; delivery is quoted separately.
Write to us by e-mail or WhatsApp with your room, your loudspeakers and your sources, and we will tell you plainly whether an Atlas fits.