Rosewind
Lost in Translation
In a follow-up review of the Benz Micro Gullwing SLR by Alan Sircom, he mentions that "there has been discussion" (where?) that "the non-iron ruby/neodynium generator" of this cart "is not a fan of transformer-coupled phono stages" (Alan Sircom, "Equipment Review: Benz-Micro SLR Gullwing", Hifi+ 85).
Another tid-bit from that article states that the solid state phono stage of Benz Micro, Benz Micro PP1 Lukascheck T9, seems to be fixed at a 22K load. Quite a high load for this cart that has an internal impedance of 38ohms - similar to what is required for a Denon 103, by the way.
A headamp seems to be the way to go with the Gullwing SLR, but a good SUT also works, however, perhaps not to perfection?
I have a Partridge 977 SUT (6:1) that loads the Gullwing SLR with 1305.6 ohms (47000:36) and gives my Croft Riaa R a little over 2mV to work with. The gain should just be sufficient, but I still have a nagging feeling that the Croft Riaa R would like a little higher gain.
I have looked at different transformer-based MC Step-up transformers based on Lundahl and Haufe. I know that there are other transformers around, but the transformers all have in common that they cannot dispense with the laws of physics and give the Gullwing SLR both perfect gain (5mV) and provide a perfect load of >400 (going up to 22K or what?).
6:1 gives 1305.6 and 2.10 mV (2.04mV - after deduction of impedance dampening)
8:1 gives 734.4 ohms and 2.8 mV (2.66 mV)
10:1 gives 470 ohms and 3.5 mV (3.24 mV)
11:1 gives 388.43 ohms and 3.85 mV (3.51 mV)
12:1 gives 326.4 ohms and 4.20 mV (3.76 mV)
14:1 gives 239.8 ohms and 4.90 mv (4.23 (mV)
18:1 gives 145.1 ohms and 6.30 mV (4.99 mV)
So if I use a SUT, it seems that I am stuck with
- low gain + perfect load
- perfect gain + too low load
Any comments on the technical aspects of this?
Another tid-bit from that article states that the solid state phono stage of Benz Micro, Benz Micro PP1 Lukascheck T9, seems to be fixed at a 22K load. Quite a high load for this cart that has an internal impedance of 38ohms - similar to what is required for a Denon 103, by the way.
A headamp seems to be the way to go with the Gullwing SLR, but a good SUT also works, however, perhaps not to perfection?
I have a Partridge 977 SUT (6:1) that loads the Gullwing SLR with 1305.6 ohms (47000:36) and gives my Croft Riaa R a little over 2mV to work with. The gain should just be sufficient, but I still have a nagging feeling that the Croft Riaa R would like a little higher gain.
I have looked at different transformer-based MC Step-up transformers based on Lundahl and Haufe. I know that there are other transformers around, but the transformers all have in common that they cannot dispense with the laws of physics and give the Gullwing SLR both perfect gain (5mV) and provide a perfect load of >400 (going up to 22K or what?).
6:1 gives 1305.6 and 2.10 mV (2.04mV - after deduction of impedance dampening)
8:1 gives 734.4 ohms and 2.8 mV (2.66 mV)
10:1 gives 470 ohms and 3.5 mV (3.24 mV)
11:1 gives 388.43 ohms and 3.85 mV (3.51 mV)
12:1 gives 326.4 ohms and 4.20 mV (3.76 mV)
14:1 gives 239.8 ohms and 4.90 mv (4.23 (mV)
18:1 gives 145.1 ohms and 6.30 mV (4.99 mV)
So if I use a SUT, it seems that I am stuck with
- low gain + perfect load
- perfect gain + too low load
Any comments on the technical aspects of this?