I have the Mod Squad Line Drive Passive pre.
I also know Pass Labs/Nelson Pass B1 buffer. (never audition)
Are they different? Why can't we call the Mod Squad a buffer or vice versa?
I believe if you have a good sounding amp that matches well with the passive, this should be the way to go. I mean do you want your amp to sound like you want or do you want your preamp to sound good? If you add a preamp and like the sound of your system better, isn't that maybe your amp is not to your liking?
I know it is a subjective thing but it makes sense. Your amp and source have gain in the first place. Why would you want to add more gain with a preamp?
I also know Pass Labs/Nelson Pass B1 buffer. (never audition)
Are they different? Why can't we call the Mod Squad a buffer or vice versa?
I believe if you have a good sounding amp that matches well with the passive, this should be the way to go. I mean do you want your amp to sound like you want or do you want your preamp to sound good? If you add a preamp and like the sound of your system better, isn't that maybe your amp is not to your liking?
I know it is a subjective thing but it makes sense. Your amp and source have gain in the first place. Why would you want to add more gain with a preamp?
Seems like you're asking a rhetorical question, or confusing engineering terminology with subjective preferences?
The B1 is an active circuit, but without gain (so a buffer). Your MS preamp seems to be a P&G volume pot in a box but no active circuitry, i.e. a passive preamp. The buffer has advantages (high input impedance, low output impedance) that may be desirable even if you don't need gain (or required, if you have to drive long capacitive cables). If you want to read the theory, this explains it pretty well: Aunt Corey's Homemade Buffered Passive Preamplifier | Stereophile.com
All the subjective stuff around what sounds best and what you prefer is just that - subjective.
EDIT: The gain in a preamp is (mostly) a leftover concept from when signal sources were turntables, tuners and tape decks that did not have enough power to fully drive a power amp. Today it might be obsolete - as Nelson also explained in the original B1 article.
The B1 is an active circuit, but without gain (so a buffer). Your MS preamp seems to be a P&G volume pot in a box but no active circuitry, i.e. a passive preamp. The buffer has advantages (high input impedance, low output impedance) that may be desirable even if you don't need gain (or required, if you have to drive long capacitive cables). If you want to read the theory, this explains it pretty well: Aunt Corey's Homemade Buffered Passive Preamplifier | Stereophile.com
All the subjective stuff around what sounds best and what you prefer is just that - subjective.
EDIT: The gain in a preamp is (mostly) a leftover concept from when signal sources were turntables, tuners and tape decks that did not have enough power to fully drive a power amp. Today it might be obsolete - as Nelson also explained in the original B1 article.
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Whenever i compare passive vs active, i find active better sounding. Assuming active is working as supposed to.
As I had mentioned, I was just saying it makes sense that passive SHOULD work better (technically) if your other sounding equipment is sounding good already for you. I think an active preamp can sound better than a passive but then I am saying maybe the amp or something else is to be blamed. I am just saying passive pre is an innocent unit in your system. It can sound bad if your amp/source is no good. Obviously, your speakers should be good, etc. etc. long subject I know but I am again saying this was a technical approach from my end.
Once again, I think you're confusing the technical part (how it works) with the subjective part (how you perceive the sound). A passive pre has a high-ish output impedance which will act together with the capacitance of your cables to affect the frequency response. You may still perceive this as being "uncoloured" or "better sounding", but to say that it is inherently "better" sounding is a bit of stretch IMHO.
No it's a volume control (and possibly an input selector) then...
Once again, I think you're confusing the technical part (how it works) with the subjective part (how you perceive the sound). A passive pre has a high-ish output impedance which will act together with the capacitance of your cables to affect the frequency response. You may still perceive this as being "uncoloured" or "better sounding", but to say that it is inherently "better" sounding is a bit of stretch IMHO.
No it's a volume control (and possibly an input selector) then...
I am talking about the “no added gain part”. Again, yes audio is subjective like most things in life.
passive is just an attenuator
same as volume pot on amp's input
has very poor driving ability, must be followed by high impedance input
active completely separates signal source from amplifier
may add some desirable harmonic enrichment (distortion)
(there is no active without distortion)
passive sounds flat and boring, active sounds dynamic, juicy and fun
is your passive followed by and amp with volume pot on input?
if it works for you, be happy and do not ask if you do not like the reply
same as volume pot on amp's input
has very poor driving ability, must be followed by high impedance input
active completely separates signal source from amplifier
may add some desirable harmonic enrichment (distortion)
(there is no active without distortion)
passive sounds flat and boring, active sounds dynamic, juicy and fun
is your passive followed by and amp with volume pot on input?
if it works for you, be happy and do not ask if you do not like the reply
what i wrote does not apply to step up transformer based passive pre, but those have even worse output impedance
@adason: Thanks but who said I didn’t like the reply. What a rude comment. I just said technically it makes sense not to amplify/add gain/ to the already gained components. How did you get that I didn’t like the replies? I actually wanted to ask the difference between MS and B1 and got my answer. You don’t have to be an ... about it.
Dear jancelo,
The sound of the amp as you perceive changes when the input source characteristics change. For the three conditions of 1. only source, 2. source with passive pre, & 3. Active buffer, your amp input sees different conditions. Like source 1.Level, & 2. Impedance. So, your amp may sound different for the different conditions. In effect, it is not only the level but also the source impedance, as seen by the amp is to be considered.
Of the three, the one with Buffer is preferred by some as it offers high impedance to the source and low impedance to the amp, which are benevolent conditions.
--gannaji
The sound of the amp as you perceive changes when the input source characteristics change. For the three conditions of 1. only source, 2. source with passive pre, & 3. Active buffer, your amp input sees different conditions. Like source 1.Level, & 2. Impedance. So, your amp may sound different for the different conditions. In effect, it is not only the level but also the source impedance, as seen by the amp is to be considered.
Of the three, the one with Buffer is preferred by some as it offers high impedance to the source and low impedance to the amp, which are benevolent conditions.
--gannaji