DA08SE 300B - the name tells most of the story. Dignity Audio is a Hong Kong firm specializing in high quality output transformers, and they have produced an eight-watt single-ended amplifier using the 300B triode as the output device.
The designers began with a realistic insight into how modern systems work and designed an amp with everything you are likely to need, and nothing that you don't. Many integrated amps provide four or more inputs, two sets of outputs, and often include a way to separate the preamp from the amplifier. All of these features seem like a good idea but seldom are used, while they increase the complexity and cost of the design. In most cases you use only one input, so only one input is provided. A single speaker is connected to an amp, so there's only one set of terminals.
Here's where things get interesting. If you use a separate power amp, you're obliged to find a preamp, a set of interconnects, another power cord - and a simple system rapidly gets complicated. The Dignity design has a single control, a volume potentiometer, on the front face. On the back is a switch to adjust to the speaker impedance. It's a nice touch, and the 16 Ohm setting in addition to the more common 4 and 8 is welcome. Think of the DA as a single-channel, single input integrated amplifier. It does not come with a remote control, and despite all of my complaints on the topic, it's not really very important.
The designers' other insight was that some modern systems involve more than two channels. The Dignity chassis is narrow and fairly deep, which means you could push a group of them together (allowing for adequate ventilation) if you had a multichannel rig. You're never stuck with more or fewer channels than necessary, and you can set channel balance easily.
The input sensitivity is 200 millivolts, which means any conceivable line level signal will drive the amp to full output. Electro-Harmonix Black Legend 300B tubes are standard. For an extra $20, you can get the E-H Gold. As in many 300B circuits, a single 6SN7 tube is in front. The amps cost $799 and weigh fifteen pounds each.
The design offers some obvious advantages. Since they're monoblocks, the Dignity amps have a power supply dedicated to each channel, and they offer infinite channel separation. They can be placed very close to the speakers, which may improve coupling.
The sound was surprising on two counts. If I weren't familiar with 300B tubes, I would guess that the amp puts out about 20 watts. It certainly drove my modified Cizeks (about 89 dB efficient) to loud levels in a large room. They would have been terrific on the Silverline Sonatinas that passed through the system last year. Dignity says the apparently larger power comes from the Permalloy output transformer, which permits the amp to maintain its full power rating into the treble range. The claim is that lesser materials roll off the top, which results in the characteristically soft sound of single-ended amps. The manufacturer also wants you to know that Z11 silicon steel laminates are used in the AC transformer and filter choke, materials more expensive than the competition uses, with commensurate improvement in performance. They may be right. What I can say with assurance is that this eight watt amp sounds louder and more powerful than others of my acquaintance.
The other surprise was the sound quality. We are told that the 300B was designed for theater use and thus emphasizes the midrange, and that it emphasizes the vocal range. This seems specious, and the Dignity demonstrates - as do the VAC amps - that the 300B is a linear device which does not color the sound when used properly. My impression with the stock E-H tubes was that the amp had a slightly analytic character, with the drive of pentodes like the 6550/KT88. The amp sounds powerful and dynamic, but lacks a little of the finesse I associate with SET amps and with the 300B tube.
This limitation was removed when I placed the E-H Gold in the circuit. There was more ambience, a greater sense of space and air at the top. This was the famous SET sound without the feeble bass and attenuated treble.
I thought back to the first SET amp I heard, the Cary 300SE. It's gorgeous, with tubes sprouting from a chrome chassis and the transformers arrayed in an arc at the rear. It's a wonderful piece of industrial design: even the control knobs are contoured for good feel. Of course it cost more than four thousand dollars when first seen, almost ten years ago. The Cary has the lovely SET midrange, along with untrustworthy behavior at the frequency extremes.
I returned to the Dignity units. They aren't as pretty but they are more honest, and the price, even with upgraded tubes, is lower than a used Cary on Audiogon. For musical purposes, the choice is simple: buy as many Dignity amps as you need and enjoy yourself.
Buying Dignity amps is safe. The importer is Monarchy Audio, a respected and well-established firm whose own products we've all used over the past decade. C. C. Poon's customer support is superb. Dr. Poon, you have another winner.