lynn_olson
Responses from lynn_olson
| Spatial Audio Raven Preamp Well, our circuit is not an afterthought. The Raven is a small power amp, with no resistors in the signal path, but it is limited in scope to medium-impedance headphones. Supporting 8 to 40 ohm headphones would require a complete re-design and a s... | |
| Spatial Audio Raven Preamp 300 ohms sounds about right. The output transformer is a step-down type, with ratios of 4.5:1 and 9:1. The previous Spatial preamp, the DS, uses a cathode follower instead of an output transformer. The output impedance is about the same, but a tr... | |
| Spatial Audio Raven Preamp There is no headphone circuit in the Raven. There are different taps on the output transformer, like a tiny power amp, and the headphone output is simply a different turns ratio. You could use planar headphones with a 30 ohm impedance ... nothing ... | |
| I need a replacement preamp for a TV pre tuner and stereo system. As the co-designer of the Raven, but also a big fan of multichannel sound (going back to the invention of the Shadow Vector quadraphonic decoder in 1973), I’d advise simply getting the PS Audio preamp repaired. (Yes, we could make a 5.1 version of... | |
| ??? WHY WHY WHY ??? Class A vs Everything Else Keep in mind that nearly all audio amplification is done in Class A: Class AB or Class D stages are only used in the final stage of amplification to drive inefficient loudspeakers. (Speakers with a 1% conversion efficiency are actually "efficient"... | |
| ??? WHY WHY WHY ??? Class A vs Everything Else Ralph, I hate to disagree, but a pure Class B amp (like the Quad 405), switches from the upper set of transistors to the lower set with no region where both are operating. Class AB has an intermediate region where both are operating. In a typical... | |
| 300b lovers If my vague memory serves, a neighbor of mine, Thom Mackris of Galibier Design, has been building an amp similar to yours. The lineup is: 1/2 6SN7 RC-coupled to a triode-connected 6V6 driver, with SE IT coupling to the 300B grid. Isolated B+ suppl... | |
| 300b lovers Hi Alex! Unfortunately, I think you are limited by the maximum DC current the interstage will accept. As Ralph mentions above, SET transformers, whether interstage or output, have air-gaps in the core so they can tolerate the DC offsets. This has ... | |
| ??? WHY WHY WHY ??? Class A vs Everything Else The choice between Class A operation vs Class AB comes down to a simple decision between: (A) Inherent low distortion and absence of device switching over the entire waveform, and also the least efficient mode of operation. (AB) Significantly hi... | |
| 300b lovers Don and I wanted to avoid unobtanium vacuum tubes, while leaving the option of "tube rolling" up to the owner. All we ask is the owner uses matched pairs, whether vintage or modern. This retains DC balance while keeping distortion low ... with typ... | |
| Spatial Audio Raven Preamp User Experience Here's an early review of the Raven and Blackbirds: YouTube Review of Raven and Blackbirds | |
| ATC SCM150 Amp and Preamp recommendations Side note: if you are serious about 1 kW/channel amps, you’re going to need an electrician to install a dedicated 20A circuit going back to the breaker box. That will also give cleaner, lower-noise feed to the audio electronics. Improving the wiri... | |
| Spatial Audio Raven Preamp User Experience The soundstage is enormous, although if the recording is poorly panned and the reverb not that great, it only goes a little way beyond the speakers. On the other hand ... if the reverb is natural, or classic EMT plate from the Seventies and Eighti... | |
| Spatial Audio Raven Preamp User Experience Well, I’m hardly objective, but I didn’t actually hear a Raven until fairly recently. When you design a product, you imagine how it will sound in your mind’s eye ... you do have a goal in mind ... but actually hearing the device up and running can... | |
| 300b lovers Thanks for the update, Don. Yoder, there was a lot of progress sonically after the first prototypes. What we have now is actually simpler in some ways. We went for a pair of spacious monoblock chassis mostly to simplify assembly, and to improve c... |