Voltage mode vs current mode phono stages


Can someone explain the differences in layman's terms and why is one better than the other? 

rsf507

@ledoux1238 , Yes, I will report on what I think in my system. That is a lot of stuff to cram into a Lino C! I was going to get a Lino C but it turns out the Seta L plus is a better unit even though it is less versatile. 

Most of the differences we hear are in amplitude variation across the frequency band, bright, dark, warm, vivid are all caused by frequency variation to which we are quite sensitive. These variations can be caused by intension, our systems, resonances anywhere and acoustics and are way more prevalent than other errors such as distortion and group delays. 

 Isn't the difference between a 'warm' and 'lean' sounding system a shift in frequency responses? 

@ledoux1238 IME on a system level that is often caused by distortion. The ear assigns a tonality to all forms of distortion. Lower orders (2nd- 4th) add warmth and they can mask the presence of the higher orders. If the higher orders are not masked, even in tiny amounts they cause harshness and brightness. The ear is keenly sensitive to them as it uses them to sense sound pressure.

For example in a phono section to know whether its a frequency response error causing the tonality or distortion, you have to measure the phono section with an inverse RIAA network to see how accurate it is. If its has flat response but sounds bright, distortion is likely the cause.

Boothroyd, LOMC cartridges, like the Lyra cartridges you mention, will have inductance in the low micro-Henry range.  The low output MI cartridges made and marketed by SS have an inductance in the low milli-Henry range.  In other words, the inductance of their LOMI cartridges is about 1000X higher than that of a Lyra or other typical LOMC.  (This is no attempt to critique the SS cartridges; I actually prefer MI cartridges over most other types, and I am grateful to SS for carrying the MI banner.) The point is that level of inductance might affect the cartridge's capacity to produce signal as current, especially at high frequencies. Thus I am curious about what happens when you mate a Sussuro, for example, with a current driven phono stage.

@lewm Since the cartridge functions as the input resistor to the opamp, the impedance of the cartridge affects the gain of the circuit (as you probably know, the gain of an opamp will be the ratio between the feedback resistor and the input resistor). This suggests that as the impedance of the cartridge goes up, the gain of the circuit goes down, which is probably good since the output of the cartridge will be higher.

I've not messed with this circuit to any great degree, so I don't know what constraints might exist, but I'm sure there are limitations- there always are. I just thought I'd point this first bit out.