Jump to content

Is a preamplifier really necessary?


Recommended Posts

Hello, I have a question and maybe someone can answer it for me.

As an audio set I have a Cambridge CXN V2 media streamer, Perreaux SA2 preamplifier, a Dynaco ST70 tube amplifier and Chorus 1 as speakers.  Now, however, the Cambridge media streamer also has a built-in preamplifier (volume control).  And since I only use 1 audio source, I don't need an input selector.  As a test I have now removed my preamp from my system and connected the Cambridge mediastreamer directly to the Dynaco tube amp and control the volume via the cambridge instead of the preamp. 

 

Now my question is, except for controlling the volume and the audio input, what does a preamp do with the sound?  Can I just as well leave out the preamp, or does the preamp also make small improvements to the sound?  I don't really hear a difference that quickly.  So Is this what a preamp only does?  Input selector and a volume control?  Or does something also happen to the audio signal that can improve the sound quality?

Link to comment
Share on other sites

Preamps generally will have some sort of EQ or Tone Control that can modify how the sound is presented to you.  If I'm not mistaken, most integrated pre-amp systems that do not have either of these will generally run flat.  For people like me that run flat anyway, that isn't a big deal, but for others it is a huge deal.

 

Looking just at a glance at the preamp you mentioned though, aside from the balance control and input switching, you are not likely to hear a difference unless the Perreaux is sonically much different from the Cambridge.  Generally, I've been pretty satisfied with how Cambridge gear sounds, so if you aren't a super critical listener, you won't notice a difference in this case.  In many other cases though, that may not be the same.

Link to comment
Share on other sites

Like you, I don't use EQ or tone control, I run flat.  As for your comment as to whether or not I am critical listeners.  Yes, I think I am 😏.  I try to make the audio sound as musical and beautiful as possible to my taste. And with adjustments I try to arrive, step by step, at the ideal sound.  And hence my question, even though I don't hear a difference so quickly, but if I get the answer that a preamplifier will somehow improve the sound, even if it is still minimal, I reconnect the preamp again. 

  • Like 1
Link to comment
Share on other sites

Interesting link 👍🏻. As you may have noticed, English is not my native language, so it is a bit more difficult for me to understand the essence of the story. But if I understand this article correctly, a preamplifier does nothing with the audio signal itself. It increased  the signal voltage so that it is usable for the power amplifier, you have access to an EQ, input selector switch, volume control and that's it.  This is all a preamplifier does. It doesn't add or enhance anything to the audio signal itself.

So if understand it correct, if you don't need any of these features (I can control the volume with the Cambridge) , you might as well remove the preamplifier? 

Link to comment
Share on other sites

19 minutes ago, Flevoman said:

Interesting link 👍🏻. As you may have noticed, English is not my native language, so it is a bit more difficult for me to understand the essence of the story. But if I understand this article correctly, a preamplifier does nothing with the audio signal itself. It increased  the signal voltage so that it is usable for the power amplifier, you have access to an EQ, input selector switch, volume control and that's it.  This is all a preamplifier does. It doesn't add or enhance anything to the audio signal itself.

So if you don't need any of these features (I can control the volume with the Cambridge) , you might as well remove the preamplifier 

Not quite. Take a phone preamp. It comes iw RIAA EQ and will amplify the frequencies according to some standard table. The same can be said for preamps in general. Each brand has its typical sound, which has to do with the settings and the components used. 

In my experience, your brain adapts to this soon, and the difference goes unnoticed, until you start comparing a and b. 

I'm a purist myself and prefer the shortest route from source to speaker. One more thing, most integrates brands, like Denon and Marantz, have a 'pure' button to turn off most of the preamp EQ. 

 

Your setup is quite pure now, so I see no need to add something in between. 

 

Link to comment
Share on other sites

3 hours ago, Flevoman said:

Now my question is, except for controlling the volume and the audio input, what does a preamp do with the sound?  Can I just as well leave out the preamp, or does the preamp also make small improvements to the sound?  I don't really hear a difference that quickly.  So Is this what a preamp only does?  Input selector and a volume control?  Or does something also happen to the audio signal that can improve the sound quality?


 

Yes a preamplifier is necessary 

Lets look a 2 channel system ( but the same applies to multi channel) 

It distributes the information that’s on the media via left and right channels to the speakers 

A pre amplifier also separates the selectable source - be it Turntable, CD player, Radio, Auxiliary ect 

 

Now you need a seperate preamplifier if you have a power amp 

However an integrated amplifier has an inbuilt pre amplifier hence the name integrated (components) 

 

Depending on how the design topography and parts used to build the pre amp, they will all have a sound signature 

Take the above text as a recipe - change a little and the taste will follow - that is the sound signature 

 

Often I advise for a holistic approach to building a system - one component does not make a system 

But a good pair of speakers is the best foundation to a good system 

  • Like 1
Link to comment
Share on other sites

The problem is your CX2  volume control is probably achieved in the digital domain. This means depending on attenuation you will be throwing away bits. I would be surprised if you can’t hear this when directly comparing to your preamp.

 

That said, Lumin is now using a processor in its app called LEEDH which doesn’t do this. You can clearly hear the difference when comparing it to a preamp or when using the Lumin direct with LEEDH turned off in the software. The way this works is above my pay grade, but work it does and splendidly. I have never liked digital volume controls before,  but this one I love.

 

So in your situation I say don’t use the Cambridge as a preamp. But if you don’t need the additional gain of the Perreaux then look into a passive line control like a Tortuga LDR or a transformer volume control.

Link to comment
Share on other sites

2 hours ago, Full Range said:


 

Yes a preamplifier is necessary 

Lets look a 2 channel system ( but the same applies to multi channel) 

It distributes the information that’s on the media via left and right channels to the speakers 

A pre amplifier also separates the selectable source - be it Turntable, CD player, Radio, Auxiliary ect 

 

Now you need a seperate preamplifier if you have a power amp 

However an integrated amplifier has an inbuilt pre amplifier hence the name integrated (components) 

 

Depending on how the design topography and parts used to build the pre amp, they will all have a sound signature 

Take the above text as a recipe - change a little and the taste will follow - that is the sound signature 

 

Often I advise for a holistic approach to building a system - one component does not make a system 

But a good pair of speakers is the best foundation to a good system 

 

I had to read your text carefully a few times to make sure I understood you correctly, but I think you explain a bit what a preamp does, but I miss the substantiation with which you start your text "yes, a preamplifier is necessary ".  I can't figure out from your text why I would be wise to use a preamplifier.  I understand your explanation that a preamplifier can have its own sound character.  And I understand that this can have a positive effect in an entire setup.  But this also applies the other way around, it can also turn out negative in combination with the other components.  And this is also no reason why you need a preamp.  Sorry if I'm drawing wrong conclusions because I may have misunderstood your explanation

Link to comment
Share on other sites

1 hour ago, Shakeydeal said:

The problem is your CX2  volume control is probably achieved in the digital domain. This means depending on attenuation you will be throwing away bits. I would be surprised if you can’t hear this when directly comparing to your preamp.

 

That said, Lumin is now using a processor in its app called LEEDH which doesn’t do this. You can clearly hear the difference when comparing it to a preamp or when using the Lumin direct with LEEDH turned off in the software. The way this works is above my pay grade, but work it does and splendidly. I have never liked digital volume controls before,  but this one I love.

 

So in your situation I say don’t use the Cambridge as a preamp. But if you don’t need the additional gain of the Perreaux then look into a passive line control like a Tortuga LDR or a transformer volume control.

OK, If this is true then this is a strong argument.  So you're saying that if you digitally adjust the volume, bits are lost?  Is this a fact?  Because I've never heard this before.  So if I understand your explanation correctly, if I adjust the volume digitally (with the Cambridge) bits (audio information) are lost, and if I adjust the volume analogously (with the Perreaux) then I keep all of my audio information/bits?

  • Like 1
Link to comment
Share on other sites

I have multiple preamplifiers having built some of the best designs out there both tube and SS. The last one I built is one by Wayne Colburn of Passlabs who designed it for diy'ers. Excellent sounding but has not been used in over a year neither has any of the others I have. I use a Firstwatt B1 V2 buffer with no gain for volume control with no equalization or tone controls. With conventional speakers that require more power to wake up a preamplifier would be desirable for the extra oomf. If one likes using a preamplifier with tone controls they should enjoy it. After all this is entertainment. 

Link to comment
Share on other sites

`I can't speak to your specific situation....  but I once, accidently messed up my wiring.  I ended up wiring my (analog) CD player into my (analog) amp.

 

I was VERY surprised at how much nicer it sounded.....  I could not however, change sources NOR could I control the volume.  If my CD player had a volume on it (some do I think) I could have gotten by with that up to a certain volume level.

 

So "can it be done?"  I think the answer is yes.  However, are there maybe exceptions to where it might NOT work well?  I'm guessing the answer is also yes.

 

In my case, if I didn't care about lack of volume control and no other sources, it would have been perfectly fine.  My other CD player (which is in a closet) has an adjustable output so it would have fixed my volume issues.

 

I still put my preamp back in.

 

 

Link to comment
Share on other sites

27 minutes ago, Flevoman said:

 

I had to read your text carefully a few times to make sure I understood you correctly, but I think you explain a bit what a preamp does, but I miss the substantiation with which you start your text "yes, a preamplifier is necessary ".  I can't figure out from your text why I would be wise to use a preamplifier.  I understand your explanation that a preamplifier can have its own sound character.  And I understand that this can have a positive effect in an entire setup.  But this also applies the other way around, it can also turn out negative in combination with the other components.  And this is also no reason why you need a preamp.  Sorry if I'm drawing wrong conclusions because I may have misunderstood your explanation



If a system does not have a pre amp - also known as a control amp “the system would not function “ as we know it

 

Even if the power amp had a source input without any control - The speakers would receive the full wattage of the amplifiers capacity 100% of the time 


Hope that makes more sense 

Control amp is probably a better name over preamp as it is the control centre of any system 

Link to comment
Share on other sites

2 hours ago, Flevoman said:

OK, If this is true then this is a strong argument.  So you're saying that if you digitally adjust the volume, bits are lost?  Is this a fact?  Because I've never heard this before.  So if I understand your explanation correctly, if I adjust the volume digitally (with the Cambridge) bits (audio information) are lost, and if I adjust the volume analogously (with the Perreaux) then I keep all of my audio information/bits?


You have it exactly right. But if you really can’t hear any difference between your preamp controlling the volume and your streamer doing it, don’t worry about it.  But I think if you are an active listener, you will hear it.

Link to comment
Share on other sites

9 hours ago, Flevoman said:

Hello, I have a question and maybe someone can answer it for me.

As an audio set I have a Cambridge CXN V2 media streamer, Perreaux SA2 preamplifier, a Dynaco ST70 tube amplifier and Chorus 1 as speakers.  Now, however, the Cambridge media streamer also has a built-in preamplifier (volume control).  And since I only use 1 audio source, I don't need an input selector.  As a test I have now removed my preamp from my system and connected the Cambridge mediastreamer directly to the Dynaco tube amp and control the volume via the cambridge instead of the preamp. 

 

 

Removing the preamp should in theory also  remove noise    , I guess the question should be ? ,  is the Cambridge Volume control dead quiet ?

Yes , remove the SA2 , 

 No ,use  the SA2 

  • Like 1
Link to comment
Share on other sites

To answer your first question, besides volume and input control what does a pre-amp do.

 

Pre-amps are designed primarily as part of a separates HIFI system. where each item in your system is in a separate box, ie CD Player, record player, digital streamer, DAC, pre-amp going into your amp

 

 

Where as modern integrated amps (AVR) is the opposite because they have everything in one box: multiple source inputs, a DAC, a preamp , amplifier duties switching duties, multiple speaker outputs,and last digital EQ.

 

Some separate type amplifiers, typically a tube amp can benefit from a hotter signal ( greater than 2 volts ) to perform at its optimum. Some pre-amps provide this hotter signal via volume control.  Pre-amps can be tube or non tube.

 

My system is made up of a MiniDSP SHD ( streamer, DAC, preamp, EQ, ) a windows 10 PC running Audirvan Studio player /streamer which sends a digital signal via my home network to the MiniDSP SHD, XLR out to a Crown XLI 1500 out to Klipsch La Scala's and an old Velodyne Sub

 

This works great, good center stage but light on the depth of the center stage . Room 17X20 with 14 foot high ceilings

 

I just added a Schit Freya S Pre-Amp ( no tubes ) between the MiniDSP and the Crown amp.

 The Freya S provides up to 12 volts out via XLR connections. Why did I add the new preamp because in the future I will have a Decware Torii Jr which responds well to more than 2 volts input

 

What did it do, increased imaging ( center stage ) and depth. Was it dramatic no, was it noticeable yes

.

 

I hope this helps.

Link to comment
Share on other sites

 My DAC has volume controls and since I only have a single digital source I could get by without my Sunfire preamp. The reason I don't is because to me the Sunfire makes my stereo sound better, gives me balance and tone controls bass boost when needed, subwoofer pre-outs, built in crossovers for mains and subs, auto on feature and a nice remote that can change all of that on the fly quite quickly. Also the Sunfire adds to the size and depth to the sound stage-- some people might argue a good preamp shouldn't add anything but I disagree in my case its a nice piece of the puzzle that makes my system as enjoyable as it is. 

 

Horses for courses-- what works for me in my situation may not work for you in yours my advice is try it out, experiment and use your own ears as a judge as to what is best for you. There are plenty of reasons to want a good preamp but there are probably just as many reasons / situations that would render one unnecessary.

Link to comment
Share on other sites

Thank you for all the replys. 

I think I will only find the answer to my question by listening very carefully myself. I hear well-founded answers from both sides as to why a preamplifier would or would not be better 

Honestly expected the answer to be more simple 😅

Link to comment
Share on other sites

As someone with only one digital source, and a dac with volume control-albeit old digital-i wonder if a preamp is really that necessary myself? I have over $4k in a preamp suitable enough to not crush and shrink my dac as my previous preamps did. I've had it in the system and already planned to sell only to move to a somewhat cheaper model after with no phono since phono seems to be creating a lot of unnecessary heat i dont need. So the new preamp will be a few years newer and built the same but no wooden cabinet and no phono. Okay. Yet, this morning i decided to try the dac straight to amp for the first time since i purchased the vintage preamp i am using.  I now realize that all that $4k+ got me was a transparent volume control. The vintage overbuilt preamp lets my overbuilt dac shine without hinderance. The dac sounded vastly better without the other preamps i've owned. Here's the thing, my vintage preamp has no remote control. My dac has a remote control. The dac straight to amp sounds indistinguishable from the dac into the preamp which i suppose is a win for the preamp as it's doing it's job.

 

The apparent reason i can't use the dac as a volume control(from what i've been told) is because the digital volume is supposed to be bad and ancient and i will reduce too many bits. The brochure(photo posted) says i can reduce to -40 before any degradation of a 24 bit output.  My computer as my only source usually won't allow me to select output bit more than the dac can hanld. An Audio Note 0.1x i had in here wouldn't let me select anything more than 16bit 44k.  The DC-91 actually allows me to select 32bit 48k. Both in my windows settings and in my player software and the music plays fine and the dac locks onto frequency. I'm not hearing a loss of resolution right now with my power amp level low and my dac -24 volume just to get an idea of low level night time listening. I can't say for sure at -34 to -40. It's jut quiet.

 

So here's my question with my source being 32 bit and the dac built in digital  volume being set for 24 bit without distortion. Aren't i giving myself even more room to use the volume control without reduction in bits and negating the need for a preamp?

adigitaldomain.jpg

  • Like 1
Link to comment
Share on other sites

Active amplifiers do two things, add noise and distortion.  Many purists that can get away without more active devices in the signal chain do so and run as few active stages as possible because they add noise and distortion no matter what anyone tells you otherwise. Now, is the noise or distortion audible is another argument but typically depends on the levels of noise and distortion. A low noise, low distortion preamp should be transparent and not matter much, others like the warmth and happily welcome the addition of some pleasurable distortion. But the fact remains the same, the signal will come out a little different then when it went in.

 

For folks that use "power amplifiers", which are just that, they only have input and output jacks and zero control over anything else, they need a preamplifier. Some power amplifiers will come with a volume control and possibly source selection and in these examples if your sources can drive your power amp to the desired output level you do not require a preamp but you still may want one due to it's capabilities to change EQ, balance, etc... to adjust for room acoustics and listening position differences. For example I don't care for an EQ but I like balance so I run my amplifier with duel mono volume controls (similar to balance) depending on which side of the room I am working on I can turn down the speaker I am closer to and turn up the one furthest from me, when sitting centered I balance them accordingly.

 

I am somewhat of a purest, I use as few active stages as possible in my signal chain. I do not currently use a "preamplifier" because my sources can drive my amplifier to full power and I don't use tone controls. The only time is when listening to records I need a phono preamplifier but that's a completely different, everyone that listens to records needs a phono preamplifier for the RIAA EQ and gain to bring up a 5mV signal to line level. 

 

 

Things to study. Line Level.

 

Line level is the signal amplitude level you will be heard referenced in this industry. Line level is on average 1Vrms, almost every modern source of music today will output a line level. Just about every power amplifier is designed to be driven to full power by line level equipment. A preamp is for the most part a dinosaur, we don't require them like we did 70 years ago, but some still like what they can offer with their various EQ and controls.

 

If you do like the way it sounds without your preamp and you can control the volume then you don't need it.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...