Den revolusjonerende transimpedans-RIAAen "den store galningen"
Designtypen heter TRANSIMPEDANCE og er vel et design som er nytt for de fleste i dag, selv om vi tror at dette har vært på markedet i en del år, men absolutt ikke utbredt. Vi vet at det ihvertfall er ên konkurrent men den mener vi har en pris på 400 000 - 500 000 kroner.
RIAAene vi er vant med fra før er spenningsstyrt mens transimpedance riaaer styres av strøm fra pickupen og ikke spenningen. Inngangssignalet er altså strøm mens utgangssignalet er spenning.
Så til det virkelige behagelige: Med PHONO LOCO (og little LOCO) trenger vi ikke å tenke på hvilken impedancesetting vi bør bruke. Vi er helt fri for denne problematikken. Altså - INGEN impedance setting.
Gain setting er også nesten irrellevant da de fleste pickupenes strømleveranse er tilnærmet like til disse RIAAene. Men det følger med et ekstra sett med motstander for finjustering av gain.
Som vanlig på alle Sutherland RIAAer - ingen "dip switch" brytere av noe slag. Ingen mulighet for "vakkel" og dårlige kontakter. Her gjelder total enkelhet
Kriteriet for å kunne bruke Store Loco:
- MC pickup (ikke high output MC)
- Pickup-jord må ikke være koplet til skjerm eller chassis
- Balansert (XLR) kapling fra pickup / tonearm
Some Loco Facts:
The Phono Loco is loco for users, dealers, reviewers, distributors and Sutherland Engineering. More importantly, the Phono Loco took full advantage of its off-the-chain design freedom. It delivers an exquisitely beautiful performance.
Marketing wise the Phono Loco is a disaster. There was a complete disregard for market acceptability. All design decisions were based on optimal engineering. It was all about performance possibilities. Marketing was thrown under the bus.
Unlike the other designs, the Phono Loco is totally focused as a specialized transimpedance unit. There is no concession to flexibility and options. With that clutter removed, the circuit can be refined and optimized to ONE goal. The Phono Loco does not hedge it’s bets. It is ALL on transimpedance.
The Phono Loco demands a balanced input signal. The circuit requires both connections from the cartridge coil to float with respect to ground. There was no bending around, or patching, or compromising to make it accept a single-ended signal.
Do not waste your money on expensive RCA to XLR adapters. Get the correctly balanced XLR cable from a good cable manufacturer. If you are not willing to get a balanced cable for the input connections, you should buy a more conventional phono preamp.
- Q What Does Transimpedance Mean?
A transimpedance amplifier input looks like a virtual short to the input signal. The input voltage is therefore zero. The input signal is the current going in/out of that virtual short. The input current is multiplied by the gain (in Ohms) to give an output voltage corresponding to the input current.
- Q What Are The Loading Options?
There are no loading options or concerns. A current input stage (transimpedance) input is a virtual short. That topology obviates load resistor selection. The current going into that short is then amplified.
- Q Can I Use a MM Cartridge?
You are welcome to try. It is unlikely to work very well.
- Q Will It Work With […] Cartridge?
We expect the Phono Loco to work very well with most MC cartridges. But there is not yet a body of info available. We will keep a user forum page updated so experiences can be shared.
Conventional voltage amplifiers express gain in dB (as the ratio between the input voltage and the output voltage). With a transimpedance amplifier, input is current and the output is voltage. For that topology, gain is expressed in Ohms. Gain is approximately 10k Ohms at 1 kHz. Most MC cartridges will work well at the medium gain setting. There is also a low (voltage down 6dB) setting and a high (voltage up 6dB) setting.
- Q Will It Work With […] Cables?
Most audio signal cables are designed to transfer voltage changes. The Phono Loco input voltage is zero and doesn’t change. What does change is current. That is generally a favorable condition for cable performance
- Q Since there is a unique interaction between the cartridge, phono cables, and Phono Loco, how do I avoid expensive experiments?
If your dealer has taken on the Phono Loco, they will have the experience to help build a superb analog playback front end. Your dealer will have explored various combinations. You don’t have to spend your money until you personally experience the winning combination.
Three more nights of listening have confirmed what I heard the first. In other words “Along with an increase in resolution, the Loco exudes an unmistakable sense of ease”. Has a complete lack of congestion in its delivery of music that is very organic in nature and a complete joy to experience.
- William T.
Using both the Lyra Etna & Koetsu Onyx, listening resulted in an incredible ease, openness and complete lack of mechanical artifacts. Music was more expressive in terms of dynamics and tonality. I was overcome with the feeling the system wasn’t working as hard as before and that musical images were just popping and blooming with a nice increase in musical textures with complete control and ease. Overall, very natural.
- C. S.
Ron: I installed the Phono Loco prototype in our reference system without even telling anyone. As they were walking by in the hall, the store owner and several others heard the music playing. They came in to find out what had so profoundly improved the system. Took it to a new level.
- C. K.
When matched with the right cartridge, the Loco is among the finest phono stages we have heard. For example, the Loco seemed to have a true love affair with the AMG Teatro cartridge mounted to the AMG Viella turntable. This match of equipment had it all…dynamics, wide open side stage, delicate highs, and deep tight bass.
It took me totally by surprise. I expected different…a change in flavor…marginal improvements. What I heard was something much more like music. It’s as if something that had been missing or lost in the experience was suddenly back. There is a density there that is hard to put into words. Everything is just so much more complete. It’s not subtle
- Bill B.
Presents the music effortlessly. No effort, no straining, no holding back.My enjoyment of the piece is going up and up. Couldn’t be more happy. Ron: This is the best piece of gear I’ve ever added to my system. Cannot thank you enough for getting me involved in the beta testing. Can’t wait to put on my next record. Can I buy this unit?
- M. S.
While beta testing the new Loco, my wife joined me. She loved the new level of musicality. This happened while we were in the middle of moving to a new house. An environment of packing, hassles, stress and unexpected expenses. My wife said “You should buy that.” I did.
- Bill T.
It’s ***** unbelievable!!! This thing is truly sensational. I have been test driving your first cut prototype and loved it!!! But this new production prototype ? It’s a whole ‘nother level. I am getting dynamics and texture that I’ve never had in my system. And it is all so effortless. And quiet! Very, very inviting. I dove pretty deep and made it a very late night. Duke Ellington, Tony Joe White, Count Basie, Cephas and Wiggins, Peter Gabriel, Junior Wells, Woody Herman. Everything I threw as it sounded like the thing was designed to showcase that record. Dragging today, but it was well, well worth it. Anyway, just letting you know that in my estimation you’ve got yourself a winner.
- S. M.