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[ohhgourami]

A lot of you have been trying to convince me to rid of my audio-gd Master-1 preamp and I realize that it's holding my system back. Seems like you guys want to steer me towards getting a passive pre. I don't know enough the differences so I want to know the pros and cons to using a passive pre. Some recommendations would be nice. Keep in mind I have some requirements like having a remote and balanced. I don't need a lot of inputs and outputs and will only be for headphones through a Krell FPB 300cx power amp.

This Khozmo seems to fit the bill nicely: http://www.khozmo.com/balanced_stereo.html

Also why are most, if not all, the high-end preamps are active?  I've been keeping my eye of for sale sections for a Krell Evo 222 because I'm a sucker for Krell stuff. I have a hard time believing it won't sound amazing.

[n3rdling]

Khozmo steppers are known for being unreliable.  I'd skip them.

[DaveBSC]

A lot of you have been trying to convince me to rid of my audio-gd Master-1 preamp and I realize that it's holding my system back. Seems like you guys want to steer me towards getting a passive pre. I don't know enough the differences so I want to know the pros and cons to using a passive pre. Some recommendations would be nice. Keep in mind I have some requirements like having a remote and balanced. I don't need a lot of inputs and outputs and will only be for headphones through a Krell FPB 300cx power amp.

This Khozmo seems to fit the bill nicely: http://www.khozmo.com/balanced_stereo.html

Also why are most, if not all, the high-end preamps are active?  I've been keeping my eye of for sale sections for a Krell Evo 222 because I'm a sucker for Krell stuff. I have a hard time believing it won't sound amazing.

Pro's to using a passive - extremely simple signal path, zero contamination from AC supply, power supply, or anything else. Single input versions amount to little more than connectors, some wire, and some type of pot or stepper. It doesn't get simpler than that. Con's - passives are poor at driving long lengths of cables. If the source has low output voltage (usually not a problem for balanced sources which generally have 4-6V output) a passive can have trouble.

The major con though, and the reason why passives are generally niche devices, is that they can overly soften the sound and/or limit bass response. That, and passives generally work best if they are designed to work with the input and output impedances of the components they are being used with, rather than being "one fits all" as most active pres are. Remote control is also pretty rare among passives because you're obviously not going to have some sort of chip driven VC like a lot of modern pres. You need a moving part, and therefore a motor to drive it, which will obviously have to be electrically powered, defeating some of the purpose.

One fairly clever pre that attempts to bring the best of both worlds is the W4S STP-SE. You get a remote, full display, balance control, and just about everything else that a typical active pre has. The volume control is resistor ladder, and the actual preamplification is passive, until the gain level reaches a certain point, and then the active gain stage kicks in, making it a semi-active design. I haven't heard it myself, but supposedly it's quite good.

If you have other Audio-GD components and if Krell CAST is compatible with Audio-GD, that might be a good match. Otherwise I wouldn't recommend Krell, well I wouldn't recommend Krell anyway, but if you have to use the SE or XLR jacks instead of CAST, I really wouldn't recommend Krell.

[ohhgourami]

I've been moving away from audio-gd equipment, but I had a full ACSS/CAST ecosystem at one point. I've upgraded to a Yggy and have realized the Master-1 induces noise floor into the system.

Any particular reasons why you don't recommend Krell?

[uncola]

I'm also curious about passive preamps.. I got a super basic model to use temporarily with my goldmund clone speaker amp that is arriving tuesday.  But I've considering other models like the firstwatt b1 bufferred passive and the tortuga ldr diy pcb which is also passive but uses power for non gain things

[mickeyvortex]

You also have the Schiit Sys and Emotiva's control freak. I could be wrong but i think they are preamps. Stick to short cable lengths between source and amp/monitors. Schiit recommends less than 3 meters i think.
    I was under the impression that active preamps are a remnant of the past where line level signals were very weak (turntables). signals of a digital origin are considerably more powerful. For eg, most DACs should output up to 2 vrms.

[DaveBSC]

I've been moving away from audio-gd equipment, but I had a full ACSS/CAST ecosystem at one point. I've upgraded to a Yggy and have realized the Master-1 induces noise floor into the system.

Any particular reasons why you don't recommend Krell?

All of my past experience with Krell has been varying degrees of negative. Cold, sterile, analytical, etc. Most of the Krell stuff I've heard has been as inviting as a hospital intensive care unit. Krell will also put their name on absolute garbage, like their integrated amps that self destruct if asked to drive anything harder than 50W @ 8 Ohms.

The Mark Levinson brand is definitely a shadow of what it once was, but the No 326S is a seriously good pre. The older No 380S isn't quite in that same league, but it's also way more affordable, typically around $3K on the used market for a good one. At that price level it's still hard to beat imo.

[DaveBSC]

I was under the impression that active preamps are a remnant of the past where line level signals were very weak (turntables). signals of a digital origin are considerably more powerful. For eg, most DACs should output up to 2 vrms.

Not really. If you're using a low output MC, your phono pre may need to apply 60dB of gain, maybe even more than that, before the signal is strong enough to be sent on to any active linestage. No preamp without a dedicated MC phono input can deal with tiny signals like that, regardless of whether its active or passive.

The reason why preamps in general are starting to fall out of favor is that fewer and fewer people need to be able to switch among 4 or 5 analog sources. Multiple sources are now being handled by the DAC, which may also have its own volume control.

Actives still definitely have their uses though. A passive pre that can handle 7 inputs, a tape loop, and drive SE and balanced out simultaneously like the 326 I don't think would be possible.

[ohhgourami]

All of my past experience with Krell has been varying degrees of negative. Cold, sterile, analytical, etc. Most of the Krell stuff I've heard has been as inviting as a hospital intensive care unit. Krell will also put their name on absolute garbage, like their integrated amps that self destruct if asked to drive anything harder than 50W @ 8 Ohms.

The Mark Levinson brand is definitely a shadow of what it once was, but the No 326S is a seriously good pre. The older No 380S isn't quite in that same league, but it's also way more affordable, typically around $3K on the used market for a good one. At that price level it's still hard to beat imo.

I wouldn't describe the Krells I've heard in those ways.

[Marvey]

Krell sounded more like that in the 90s.