Passive pre-stage / power amp / speakers.

[Wil]

Dear music friends,
I am busy with a new set up with; Rebuild Quad ESL63, Audiophonics 450 with upgrade op-amp, A passive pre-stage.
The Quad rebuilders demonstrated with Schiit amps. For me it sounded great.
A friend is willing to buy a high end passive pre-stage (no pre amp). He can build three different stages, costing 750, 1500 and 3000 euro/dollar.
I can choose witch one I prefer. But I wanna order without hearing in front to win some time. He himself plays with the 3000 stage, a Audiophonics 400 and diy horns. The sound is unbelievable realistic. I am a authorized classical musician working every day with acoustical instruments.
My question is, which stage to order? What sound can I suspect? I can also buy a cheap Schiit Sys for the time being.
I have very little technicle knowledge. His two more expensive stages exist of a lot of hand made bobbins (a few hunderd hours work)
KInd regards,
Wil

 

[voodooless]

He can build three different stages, costing 750, 1500 and 3000 euro/dollar.

My question is, which stage to order?

How should we know? I would buy none of them.. sounds like a lot of money for a passive attenuator. Do you even need it? Doesn’t your source have a volume control?

What sound can I suspect?

None whatsoever… these kinds of devices have no sound, like moist electronics.

Stop thinking that sound reproduction is anything like a musical instrument.

 

[LTig]

Dear music friends,

Welcome to ASR.

I am busy with a new set up with; Rebuild Quad ESL63, Audiophonics 450 with upgrade op-amp, A passive pre-stage.
The Quad rebuilders demonstrated with Schiit amps. For me it sounded great.
A friend is willing to buy a high end passive pre-stage (no pre amp). He can build three different stages, costing 750, 1500 and 3000 euro/dollar. I can choose witch one I prefer.

A passive preamp just contains a switch (to select the source) and a potentiometer. Even € 750 would be too much.

But I wanna order without hearing in front to win some time.

Preamplifiers are a solved problem since the late 70s (see the review of the Yamaha C2). Although you will hear differences when comparing them, those differences are not caused by the real performance of the preamp but by a lot of other sources our brain uses to create the final experience (your mood, knowing the price, seeing the design, ...). Also without level matching to less than 0.1 dB (which requires a measuring instrument) the somewhat louder device always sounds better.

That said, it is very easy to fool yourself in a listening test if it is not properly controlled.

He himself plays with the 3000 stage, a Audiophonics 400 and diy horns. The sound is unbelievable realistic. I am a authorized classical musician working every day with acoustical instruments.
My question is, which stage to order? What sound can I suspect? I can also buy a cheap Schiit Sys for the time being.

Electronics are a solved problem as well: if preamp and poweramp are properly designed they will sound transparent, which means they have no influence on the sound coming in. Speakers and their position in the room however have the biggest influence on the sound (besides the recording itsself). You cannot expect an electrostatic speaker (big panel) in your room to sound like a horn speaker in your friends room. Even in the same room at the same position they will sound different as their off-axis characteristics are very different.

I have very little technicle knowledge. His two more expensive stages exist of a lot of hand made bobbins (a few hunderd hours work)

If he designs his preamps he should be able to show measurements which proof that the more expensive stages are better regarding frequency response, distortion, noise and crosstalk (there is nothing else).

With a passive preamp distortion is no problem as there is no active device involved. Crosstalk should be no problem either if the wiring is kept separate. Noise and frequency response may suffer if the resistance of the potentiometer is chosen unwisely or does not match the input impedance of the power amp. There will be a loss in high frequencies if the cables are long. There is a reason why active preamps exist.

 

[antcollinet]

Dear music friends,
I am busy with a new set up with; Rebuild Quad ESL63, Audiophonics 450 with upgrade op-amp, A passive pre-stage.
The Quad rebuilders demonstrated with Schiit amps. For me it sounded great.
A friend is willing to buy a high end passive pre-stage (no pre amp). He can build three different stages, costing 750, 1500 and 3000 euro/dollar.
I can choose witch one I prefer. But I wanna order without hearing in front to win some time. He himself plays with the 3000 stage, a Audiophonics 400 and diy horns. The sound is unbelievable realistic. I am a authorized classical musician working every day with acoustical instruments.
My question is, which stage to order? What sound can I suspect? I can also buy a cheap Schiit Sys for the time being.
I have very little technicle knowledge. His two more expensive stages exist of a lot of hand made bobbins (a few hunderd hours work)
KInd regards,
Wil

@voodooless, and @LTig have given you good advice. I'm going to try to simplify it for you a little.

It is pretty easy these days for any competent engineer to make excellently performing audio electronics - especially something as simple as a pre-amp. Typically, audio electronics is so good that any imperfections are inaudible - yes, even for trained musicians - who, though trained to hear sound, are still only equipped with human hearing capability.

The words "High End" when applied to electronics are generally used to justify high prices without any audible benefit to them (many so-called high-end devices actually have poor measured performance). This is a real problem in the audio market, and many people are being deceived.

Passive preamps in particular have almost nothing in them. But also, there is no advantage to passive, and some significant disadvantages (the high output impedance of the volume potentiometer can interact with cable capacitance to cause frequency response issues with longer interconnect (though whether this is audible would also be up for debate)).

Here at ASR, we make our judgements based on measurements, so we can't advise you on the devices you are considering because we have nothing to base that decision on. However, it is exceptionally unlikely there will be any real audible difference between them if they are competently designed.

Having said that, I would not advise you getting any of them (problems with passive I mentioned). I would suggest instead an active preamp which we have good measurements for:

Fosi Audio P4 - which measures excellently and is a bargain at around £100

Fosi Audio P4 Preamplifier Review

This is a review and detailed measurements of the Fosi Audio P4 budget RCA preamp. It was sent to me by the company and as of this writing, is on sale for US $80. The look is attractive enough for the class. A momentary switch turns on the unit and cycles through inputs, with a reassuring...

www.audiosciencereview.com

Fosi ZP3 - also excellent measurements and balanced IO for noise rejection - but almost double the price of the P4

Fosi Audio ZP3 Preamplifier Review

This is a review and detailed measurements of the Fosi ZP3 balanced preamplifier. It was sent to me by the company and costs US $189 (coupons available for less). Despite its low cost, the look of the unit is attractive to me. As is the functionality of having balance and tone controls. What...

www.audiosciencereview.com

Failing these— and depending on what your source is— then any number of DAC/preamp devices.

(What is your source? Streamer? Turntable? Computer? CD player, etc.)

Also - what are you wanting the pre-amp to do for you?

 

[audio_tony]

For good value passive preamps try Khozm
o https://khozmo.com/product/stereo-with-input-selector/

 

[LTig]

For good value passive preamps try Khozm
o https://khozmo.com/product/stereo-with-input-selector/

€ 400.- for passive preamp with just 2 inputs is far from being good value. € 100.- might be good.

 

[Chr1]

I use one of these. Several inputs. Output for subwoofer and a lot cheaper.

Tisbury Audio Mini Passive Preamp II

A high quality passive preamp with a stepped attenuator volume control for true transparent sound quality. Made in England.

tisburyaudio.com

(Was a fair bit cheaper still when I got mine a few years back however.)

 

[Wil]

@voodooless, and @LTig have given you good advice. I'm going to try to simplify it for you a little.

It is pretty easy these days for any competent engineer to make excellently performing audio electronics - especially something as simple as a pre-amp. Typically, audio electronics is so good that any imperfections are inaudible - yes, even for trained musicians - who, though trained to hear sound, are still only equipped with human hearing capability.

The words "High End" when applied to electronics are generally used to justify high prices without any audible benefit to them (many so-called high-end devices actually have poor measured performance). This is a real problem in the audio market, and many people are being deceived.

Passive preamps in particular have almost nothing in them. But also, there is no advantage to passive, and some significant disadvantages (the high output impedance of the volume potentiometer can interact with cable capacitance to cause frequency response issues with longer interconnect (though whether this is audible would also be up for debate)).

Here at ASR, we make our judgements based on measurements, so we can't advise you on the devices you are considering because we have nothing to base that decision on. However, it is exceptionally unlikely there will be any real audible difference between them if they are competently designed.

Having said that, I would not advise you getting any of them (problems with passive I mentioned). I would suggest instead an active preamp which we have good measurements for:

Fosi Audio P4 - which measures excellently and is a bargain at around £100

Fosi Audio P4 Preamplifier Review

This is a review and detailed measurements of the Fosi Audio P4 budget RCA preamp. It was sent to me by the company and as of this writing, is on sale for US $80. The look is attractive enough for the class. A momentary switch turns on the unit and cycles through inputs, with a reassuring...

www.audiosciencereview.com

Fosi ZP3 - also excellent measurements and balanced IO for noise rejection - but almost double the price of the P4

Fosi Audio ZP3 Preamplifier Review

This is a review and detailed measurements of the Fosi ZP3 balanced preamplifier. It was sent to me by the company and costs US $189 (coupons available for less). Despite its low cost, the look of the unit is attractive to me. As is the functionality of having balance and tone controls. What...

www.audiosciencereview.com

Failing these— and depending on what your source is— then any number of DAC/preamp devices.

(What is your source? Streamer? Turntable? Computer? CD player, etc.)

Also - what are you wanting the pre-amp to do for you?

I have read that every pre-amp has an own character. In that case I have to try several pre-amps in my system. I don't want a warm or what ever sound.
Also there must be a sound match between pre- and power amp. I sold the Spectral DMC12, because of his terrible sound. I borrowed a passiv pre amp from a friend, and the results were very good. But that thing costs 1500 euro and had a knob for left en right.

I have a Kuzma + VandenHull The Frog + Sphinx phono amp. A Philips drive + Weiss Dac 2.

 

[Mnyb]

There is no matching if the amps involved are of decent quality as they sound transparent. However if you mix and match watch out for gain and sensitivity as you want a usable volume control range and low noise .

A passive pre can be great just watch out so you keep cables as short as possible . The high output impedance can interact with the cables and input impedance of the power amp acting as a filter , a large not subtle change in treble quality would be a hint …

 

[antcollinet]

I have read that every pre-amp has an own character.

That is part of the massive mis-information (basically nonsense) in the industry.


In reproduction equipment, there is only distortion, noise and frequency response which can cause a different sound. When variations in those are smaller than the human ear can detect (and that is routinely achieved), then there is nothing that can be heard to create a "character"

Also there must be a sound match between pre- and power amp.

That is also nonsense.

I have a Kuzma + VandenHull The Frog + Sphinx phono amp. A Philips drive + Weiss Dac 2.

Ok - you do seem to have fallen into the audio industry trap. You are reading (and probably being told) a bunch of stuff that is misleading you. It is going to be difficult to let go of it - but it is possible - many of us here have done so.

On the plus side you do have an excellent Amp - of the type most here would advise you to be looking at.


My advice above about the two Fosi preamp stands, as probably the only route I am prepared to advise, while still minimising friction for you based on your preconceptions. It at least gives you a low cost stopgap while you spend a little more time evaluating the route you really want to go down on your audiophile journey.


If I was going to advise you based on what I think would be optimum for you (but you will probably struggle to accept right now) it would be:

Sell the Sphinx phono pre, and the Weiss Dac2.

Use the money to Replace them with a parks audio waxwing - and one of the many exceptionally well measuring Dacs which have a volume control. Use the digital connection between the waxwing and the dac.

Take your partner/spouse/friends out for a few meals on the money left over.


When you tell your friend about my suggestion he will probably laugh at the idea of converting your turntable output to digital - saying you will lose all the analogue sound quality. If he does - this is also nonsense. Digital can perfectly capture everything audile on the output of your turntable, and then reproduce it perfectly.


Whatever you end up doing - I hope you enjoy the result.

 

[sergeauckland]

I have read that every pre-amp has an own character. In that case I have to try several pre-amps in my system. I don't want a warm or what ever sound.
Also there must be a sound match between pre- and power amp. I sold the Spectral DMC12, because of his terrible sound. I borrowed a passiv pre amp from a friend, and the results were very good. But that thing costs 1500 euro and had a knob for left en right.

I have a Kuzma + VandenHull The Frog + Sphinx phono amp. A Philips drive + Weiss Dac 2.

Sadly, good ones don't have any character, they just output what they have input, with either some gain or attenuation, or in the case of a passive, attenuation only.

Furthermore, a passive pre-amp can't have a character, as there's nothing to affect the sound. Yes, the output impedance of a passive is much higher than that of an active pre-amp, but even so, even a few metres of decent cable between pre-amp and power amp won't affect high frequencies to any audible extent. I quite happily used a passive with my Meridian M2 active loudspeakers with 5m of cable and there was no measurable loss of high frequencies below 20kHz.

S.

 

[DSJR]

My Crown D-60s, with 25k Log pots as gain controls, absolutely HATED a passive preamp ' running into them, a slight hum resulting that nothing I did could remove. usually, these old amps are silent with absolutely no 'character' at all within their these-days modest 44WPC or so @ 8 ohms output.

 

[voodooless]

Be careful with these speakers and some Class-D amps:

High frequency impedance goes towards zero meaning this is a highly capacitive load. Some Class D amps don’t particularly like this. It would be good to check if the Purifi modules are fine with this.

 

[Wil]

I just read and saw bad reviews about the sound quality of the Fosi Audio P4.

 

[sergeauckland]

I just read and saw bad reviews about the sound quality of the Fosi Audio P4.

Really?

Fosi Audio P4 Preamplifier Review

This is a review and detailed measurements of the Fosi Audio P4 budget RCA preamp. It was sent to me by the company and as of this writing, is on sale for US $80. The look is attractive enough for the class. A momentary switch turns on the unit and cycles through inputs, with a reassuring...

www.audiosciencereview.com

Here's Amir's final comment:-
"
Conclusions
The Fosi P4 surprises with incredibly low cost while providing features such as motorized volume control and excellent performance. It simply has no weak point, other than absence of trigger. This is what happens when a company is laser focused on customer needs and excellence in engineering. "


I would be happy with that!

S.

 

[Dave TR3A]

I just read and saw bad reviews about the sound quality of the Fosi Audio P4.

Where? Please provide links to those reviews.

 

[Grotti]

I just read and saw bad reviews about the sound quality of the Fosi Audio P4.

Stick to the measurements: in case of a pre-amp it's all that matters.

 

[Wil]

And also less good reviews about the Tisbury Mini.
Both amps are rather good for what they cost. But that is not what I am looking for.

 

[Wil]

I cannot listen to specifications. I listen to music.

 

[Chr1]

But the specifications ensure that you hear the music as you should.