Your All Time Favorite Preamplifiers?

[Light Dependant Resistor]

Some people don't want a line stage to provide additional drive and dynamics as that's coloration added by gear. I'd rather a line stage do as little of that as possible.

With a well designed passive, true there is no added coloration from added by gear. Rather there is the same drive and dynamics as the music was recorded with, ..exactly as it should be. Passive types are many and everything should be considered.

 

[bazelio]

True, but they won't if they are correctly matched to the load (the amp's input impedance). Having a source with a powerful output also helps.
My little DAC has a hefty output and drives the amp quite happily (i.e. dynamics etc are OK) via the passive volume control

Electrical matching is important with passive resistor attenuators, and even then resistor configuration and even type matters. They can still flatten out the sound. The Goldpoint certainly did do so in a system where AVCs shined and source had low output impedance into 50k input impedance. And, yes, even with an AVC or TVC, the source also must be able to drive the load (the amp). There's no current gain, obviously. When I demoed Lamm phonos, they were clearly not able to do so (audibly mushy) and required a preamp. I suspected as much from looking at their spec sheet. Most sources can, but yes, there are a few that can not. In my case, the best phono I've heard was designed to work with an AVC passive.

 

[bazelio]

With a well designed passive, true there is no added coloration from added by gear. Rather there is the same drive and dynamics as the music was recorded with, ..exactly as it should be. Passive types are many and everything should be considered.

This was my point. Yes.

 

[musicfirst1]

Ok guys, back to the OP question please.

 

[bonzo75]

Electrical matching is important with passive resistor attenuators, and even then resistor configuration and even type matters. They can still flatten out the sound. The Goldpoint certainly did do so in a system where AVCs shined and source had low output impedance into 50k input impedance. And, yes, even with an AVC or TVC, the source also must be able to drive the load (the amp). There's no current gain, obviously. When I demoed Lamm phonos, they were clearly not able to do so (audibly mushy) and required a preamp. I suspected as much from looking at their spec sheet. Most sources can, but yes, there are a few that can not. In my case, the best phono I've heard was designed to work with an AVC passive.

What's the spec you look at.

Also is the phono you are referring to designed to work with AVC slagle? In that case you will have to pick up from same designer.

Do you know any non slagle phonos that work well with AVC like slagle?

 

[bazelio]

What's the spec you look at.

Also is the phono you are referring to designed to work with AVC slagle? In that case you will have to pick up from same designer.

Do you know any non slagle phonos that work well with AVC like slagle?

The first and most obvious red flag was the Lamm phono output impedance. I don't remember what else was in the spec sheet anymore. This was a few years ago. As I said previously, most sources will work well with AVC. Lamm being one that does not. You do not need to stay with the same designer. I think I explained it above, but if not, ping me in pvt. Someone (no longer on this forum) told me they tried Keith's TVC with a Lamm phono and it sounded fine to their ears. That's great, but it didn't work so well in my house an my amplifier at the time had at least 50k input impedance, so it wasn't the amp's fault.

 

[AMR / iFi audio]

I used a passive volume pot for many years together with PSE 2A3 amps and Lowther horns. Changing my passive to a Slagle Autoformer volume vas a great upgrade and a great solution for that very revealing but bass limited system.
With Altec 604 I then used a Leben RS-28CX with several different power amps mainly tube (PP kt88 and SE 300B) but also class D amps. That was a nice preamp, bass could be rather bloated with SE 300B but it revealed wonderful inner detail in voices and instruments. However, it could be a little tame on rock, thus the class Ds.
Currently, I have 2 preamps (plus the passive Slagle which I still own). A DIY Aikido using 6CG7 which I like with my Altec A5s and DIY first watt amps and a DIY first watt B1 Korg which I use on Carlsson OA51 with a DIY Modulus 86 chip amp (the distortion profile of the Korg pre can be tailored according to personal preference).
I would say that the Leben was the nicest preamp from a build quality perspective. The passive slagel autoformers where great where more gain was not needed, but extremely revealing and could be quite tiring if the source material was not tip-top. I like my Aikido and use it a lot, but the best of the lot and most flexible is probably the inexpensive DIY B1Korg.

I've heard aikido on 12AU7 and 6DJ8 it was very pleasant. I don't think I've had a chance to listen to any B1. Heard lots of good stuff about it though.
Leben RS-28CX is a really solid preamp. Tubes really have that amazing headroom that makes music sound effortless. Personally, I like to mix tubes and solid-state to get the best from both worlds.

 

[shakti]

I am currently listening to music using the transformer based

Phasemation CM-2000

passive line stage. Compared to other PreAmps I had in my gear, the CM-2000 is one of the best.
Pairing to signal source, cable length and Amp needs to be done more carefully, than with the most active preAmps,
but if it fits, you are very close to the original sound of the source.

 

[bazelio]

Look ma, no power cord!

I wasn't aware Phasemation had a TVC box. But it only makes sense.

 

[Geert1962]

Thrax Libra is for me one of the best sounding preamps today. Another great one is the Alieno preamp. Both expensive but worth every $.

 

[DoctorWhy]

For me, as someone who aspires to the very best from SOTA Digital, I long believed in "The Best Preamp is no Preamp" edict. That is, a properly designed DAC with the best implemention of a volume control (like the non decimating oversampled DVC in the Mola Mola Tambaqui or by control of the reference voltage to the actual DAC chips like those in the Metrum or Sonnet) simply could not be equaled, let alone beat.

For me now, the very best preamps, not only "do no harm" but also excel in terms of drive and dynamics, which one would expect, but also in terms of detail, air, and low level resolution!!

On top of all the above, the very best Preamps, when inserted between ones' DAC and Amplifiers, can inject a level of musicality, and indeed HUMANITY, that makes it so much easier to connect with the Artist and the performance.*

* Is this effect due to the 'colorizing' or 'editorializing' effect said to be present in essentially all preamps (usually a detractors or purists)? Poviding said preamp first 'does no harm'
I simply don't know and don't care.
.

So I recently obtained an MSB Select DAC with two power bases. The preamp function of this DAC has been widely lauded. When I ran it thru my NAGRA HD PREAMP the sound gained body and depth of soundstage. I previously had an AESTHETIX CALLISTO ECLIPSE pre amp which was the best I had previously in my system. The Nagra HD PreAmp sounds better by far. Previous preamps included ARC Ref 3, McINtosh 500 T, and Burmester.

 

[DoctorWhy]

getting away from the favorite preamp discussion, and talking 'preamp' philosophy, i have some strong views. at modest levels of gear a preamp reduces performance. extra interconnects, modest circuits, and compromised build quality do restrict transparency and get in the way of the musical message. sources going direct mostly result in a net gain. sometimes integrated units with source and active preamp in a single chassis, are best at low price points.

so i do agree with you in those cases.

less is more.......until...........more is more.

at a certain point not having an active preamp will reduce energy and substance from the music. better sources and better amps deserve the better signal delivery that a top preamp can deliver. hard to define where that line is as far as dollars. but it's easy to hear.

at the top of the food chain the very top level preamps apply extreme power supply, tech and chassis approaches to make their case. they 'dig deeper' than passive can manage to do. and many times synergize with and optimize the amps too.

Hi Mike. I completely agree. My Nagra HD PreAMP definitely improved the sound of The MSB Select DAC in my system. If I had the DARTZeel Amps, I would certainly want the Dart Pre.
Rob

 

[musicfirst1]

So I recently obtained an MSB Select DAC with two power bases. The preamp function of this DAC has been widely lauded. When I ran it thru my NAGRA HD PREAMP the sound gained body and depth of soundstage. I previously had an AESTHETIX CALLISTO ECLIPSE pre amp which was the best I had previously in my system. The Nagra HD PreAmp sounds better by far. Previous preamps included ARC Ref 3, McINtosh 500 T, and Burmester.

Hi Mike. I completely agree. My Nagra HD PreAMP definitely improved the sound of The MSB Select DAC in my system. If I had the DARTZeel Amps, I would certainly want the Dart Pre.
Rob

Would you say the Nagra HD is your personal fave Pre?

 

[dave slagle]

And, yes, even with an AVC or TVC, the source also must be able to drive the load (the amp). There's no current gain

This is only correct when the AVC / TVC is used at unity. The very nature of an autoformer or transformer converts excess voltage into available current. 6dB of attenuation results in roughly 1/4 the output impedance and 4X the available current. 12dB nets you 1/16th the output Z or 16X current. It is this current gain as you attenuate that separates the magnetic volume controls from the resistive ones.

dave

 

[Light Dependant Resistor]

This is only correct when the AVC / TVC is used at unity. The very nature of an autoformer or transformer converts excess voltage into available current. 6dB of attenuation results in roughly 1/4 the output impedance and 4X the available current. 12dB nets you 1/16th the output Z or 16X current. It is this current gain as you attenuate that separates the magnetic volume controls from the resistive ones.

dave

But sadly adds reactance, returning a quarter cycle later to the circuit. Resistance types have, as a result better linearity with audio signal

 

[musicfirst1]

But sadly adds reactance, returning a quarter cycle later to the circuit. Resistance types have, as a result IS SET better linearity with audio signal

So does this mean that 'passive' preamps with magnetic volume controls actually act 'actively' if the AVC/TVC is set at below unity? This I did not know.

 

[bazelio]

This is only correct when the AVC / TVC is used at unity. The very nature of an autoformer or transformer converts excess voltage into available current. 6dB of attenuation results in roughly 1/4 the output impedance and 4X the available current. 12dB nets you 1/16th the output Z or 16X current. It is this current gain as you attenuate that separates the magnetic volume controls from the resistive ones.

dave

Ooh yes, I was only thinking of impedance in isolation. Tha ks!

 

[dave slagle]

So does this mean that 'passive' preamps with magnetic volume controls actually act 'actively' if the AVC/TVC is set at below unity? This I did not know.

They are no more active than any other inductive device.

 

[bazelio]

They are no more active than any other inductive device.

I mean, you're really just saying power in equals power out, in the ideal case. There's no gain as in an amplifier.

 

[dave slagle]

The basic litmus I use for active vs. passive is power. Active devices require an external source of power to operate and passive devices do not. That is overly simplistic and some passive devices fail the test once you get beyond electronic parts. The chart below from here pretty clearly lays out the differences.

(edit.... The original chart had an error that contradicted the text from the link above so I deleted that line from the image.)