Preamps! Exlpain to me! :)

Beerce

Hey all, I have a question about preamps in general.

My system is 2-channel as follows:
I will be using my computer with a high-end sound card to output most of my music (aside from the vinyl), and so the only real reason I need a preamp is for the phono input for a turntable. Some preamps don't have phono, so I would need a separate phono amplifier as well if I were to get one of these. I don't have a cd player, blu-ray, etc. so I really don't need all of the inputs. In my case, I could probably get away with a cheaper preamp with a phono input, but I'm assuming that I'm not quite understanding the purpose of a preamp. There has to be a reason why some preamps are $1000 and some are $100, regardless of whether or not they have phono.

So if I wasn't going to use a turntable I wouldn't even need a preamp because I would only have one input, my computer, and I could go directly to the amplifier from my sound card. When I add the turntable into the mix, I now have two inputs which is too many for the amplifier so I need a common "hub" - the preamp. I'm assuming a preamp isn't just a "hub" for your components but does a lot more than this, I'd just like to know more about it. I guess I'm just wondering what you get by spending more money on a preamp?
In your opinion, for my setup, would I be better off finding a preamp with phono input so I can run the turntable and computer directly to it, then to the amp?

I suppose I'd like to know, if the features on a preamp that make it higher end (and therefore slightly more expensive) will even be used in my setup? If I won't even be taking advantage of the features that make a preamp what it is, would I be better off with something else?

If you're wondering, the gear I'm referring to is a B&K EX-4420 power amp and a B&K Reference 5 S2 preamp. Could I get away with a less expensive preamp in my situation, without losing quality?

Thanks a lot,
Beerce

heiney9

A computer with a "high end" soundcard is still worse than even a medioce pre-amp unless you are using an asyncronous USB output and then a nice pre-amp is still better.

Then again if you are feeding a pre-amp with the "high end" soundcard then you're not gaining any advantage. The computer soundcard is the weak link in *most* cases, unless you are using something that is for professional recording.

But it all depends on what you trying to accomplish and how picky you are........myself I'm extremely picky about my main 2ch rig.

H9

nguyendot

The best sound cards usually sit outside the pc, or are fully shielded, no? Also they usually use balanced connections.

cstmar01

I would get a good pre amp or a DAC and use it that way.

A good pre you could use the digital out from the SC would be the Peachtree series. Good DAC's and good little pre amps, or integrated amps as well.

SC to me suck, and you could gain more by getting an external DAC and just a cheap SC. Run the optical or digital out from the SC to the DAC and some DAC's will have volume control etc so then you don't need a pre amp. However if you run vinyl you would still need something, phono pre, etc for that end of it.

heiney9

nguyendot wrote: »

The best sound cards usually sit outside the pc, or are fully shielded, no? Also they usually use balanced connections.

Maybe.........computer audio is something entirely different and it can be done as good as a nice transport........but there are a lot of pitfalls and obstacles to overcome in the operating environment for the best end result.

It's usually not cheap and you have to have some knowledge, but it can be done.

USB w/asynchronus stream is the place to start currently. Using an ASIO driver eliminates all the obstacles involved.

Or using a wireless streamer like Logitech Squeezebox products.....thaose have their own pitfalls that are easily remedied as well.

Again, I'm talking if you want performance on par with some of the best cdp's and transports in comparison. I realize not everyone is looking for that kind of performance and it's more about convenience.........but you can have both!

H9

heiney9

cstmar01 wrote: »

A good pre you could use the digital out from the SC would be the Peachtree series. Good DAC's and good little pre amps, or integrated amps as well.

The sound card is still the weaklink, especially how the info is extracted. No amount of excellent down stream gear will improve a compromised digital stream. It ALL starts at the source.

H9

Beerce

Hey guys, thanks for all the input.

I know there are other alternatives to using a PC sound card, but aside from this, can someone get into what makes a preamp $1000 vs $100 and am I better off with a cheaper preamp with phono for my turntable, or will the more expensive preamp (even if it doesn't have phono) offer me better results for any particular reason? Let's assume for the sake of argument that my source is NOT my limiting factor. In this case, what would higher end preamps have to offer, and with my setup described as above, would I be taking advantage of those features found on higher end preamps, or do I really just need any old preamp to act as a "hub" for my multiple inputs (2 really).

I'm not worried about the quality of the source from my PC sound card. The analog output on this card is fully shielded with a SNR of 124 db and what I would consider a fairly decent Burr-Brown 24-bit/192kHz DAC. One of many reviews for the cards can be found here: http://www.stereophile.com/computeraudio/asus_xonar_essence_ststx_soundcards/index.html
I will also be the highest quality audio files I can get my hands on, be it FLAC or another type of lossless codec.

Thanks again, keep em comin'

Beerce

PolkClyde

Beerce wrote: »

Hey all, I have a question about preamps in general.

My system is 2-channel as follows:
I will be using my computer with a high-end sound card to output most of my music (aside from the vinyl), and so the only real reason I need a preamp is for the phono input for a turntable. Some preamps don't have phono, so I would need a separate phono amplifier as well if I were to get one of these. I don't have a cd player, blu-ray, etc. so I really don't need all of the inputs. In my case, I could probably get away with a cheaper preamp with a phono input, but I'm assuming that I'm not quite understanding the purpose of a preamp. There has to be a reason why some preamps are $1000 and some are $100, regardless of whether or not they have phono.

So if I wasn't going to use a turntable I wouldn't even need a preamp because I would only have one input, my computer, and I could go directly to the amplifier from my sound card. When I add the turntable into the mix, I now have two inputs which is too many for the amplifier so I need a common "hub" - the preamp. I'm assuming a preamp isn't just a "hub" for your components but does a lot more than this, I'd just like to know more about it. I guess I'm just wondering what you get by spending more money on a preamp?
In your opinion, for my setup, would I be better off finding a preamp with phono input so I can run the turntable and computer directly to it, then to the amp?

I suppose I'd like to know, if the features on a preamp that make it higher end (and therefore slightly more expensive) will even be used in my setup? If I won't even be taking advantage of the features that make a preamp what it is, would I be better off with something else?

If you're wondering, the gear I'm referring to is a B&K EX-4420 power amp and a B&K Reference 5 S2 preamp. Could I get away with a less expensive preamp in my situation, without losing quality?

Thanks a lot,
Beerce

What's the name of that high-end sound card?

heiney9

Beerce wrote: »

I'm not worried about the quality of the source from my PC sound card. The analog output on this card is fully shielded with a SNR of 124 db and what I would consider a fairly decent Burr-Brown 24-bit/192kHz DAC. One of many reviews for the cards can be found here: http://www.stereophile.com/computeraudio/asus_xonar_essence_ststx_soundcards/index.html
I will also be the highest quality audio files I can get my hands on, be it FLAC or another type of lossless codec.

Thanks again, keep em comin'

Beerce

Those specs don't mean much if you are using windows kernal mixer for output. K-mixer is the worst output you can use.

H9

nguyendot

heiney9 wrote: »

Those specs don't mean much if you are using windows kernal mixer for output. K-mixer is the worst output you can use.

H9

Can you elaborate? I'd like to give something a try if you could suggest.

thanks

heiney9

nguyendot wrote: »

Can you elaborate? I'd like to give something a try if you could suggest.

thanks

It's been a long time since I configured a soundcard. Do a google search on k-mixer for whatever OS you use. I currently use the USB output into an asychronous USB/SPDIF converter into an outboard dac for my office rig.

http://www.hifi-advice.com/USB-synchronous-asynchronous-info.html

http://en.wikipedia.org/wiki/Windows_legacy_audio_components

scroll down to kmixer explanation.

H9

newrival

for the short term:
there is no need for a preamp if you get a dac since it's line level at that point. You'll probably want to find one with a volume control built in, or an external line level volume control. In most circumstances a preamp is just a volume control and source selector (there is almost always a gain stage and buffer) and would tend to color the sound as opposed to help it. The only reason you might want a preamp is if you want to match component impedance and have an unusual mismatch like a really low amplifier or some such.

For the future:
add the pre when you get the TT. You're going to want (read: need) the DAC there even with the preamp. then look at phono stages when you get that far.

newrival

A-sync DACs don't solve the whole problem either. There are problems with asynchronous usb, mainly power-related noise. Ideally you'd want to isolate your DAC using an asynchronous usb-S/PDIF converter, thereby Isolating your DAC from all the potential power-related noise of your PC and minimizing jitter.

heiney9

newrival wrote: »

A-sync DACs don't solve the whole problem either. There are problems with asynchronous usb, mainly power-related noise. Ideally you'd want to isolate your DAC using an asynchronous usb-S/PDIF converter, thereby Isolating your DAC from all the potential power-related noise of your PC and minimizing jitter.

Yep, that's what I'm doing.........but again this is not my main 2ch rig. This is an office rig. I wouldn't connect a computer to my main "audiophile" rig.

H9

heiney9

newrival wrote: »

You'll probably want to find one with a volume control built in, or an external line level volume control. In most circumstances a preamp is just a volume control and source selector (there is almost always a gain stage and buffer) and would tend to color the sound as opposed to help it. The only reason you might want a preamp is if you want to match component impedance and have an unusual mismatch like a really low amplifier or some such.

A word of advice from experience..........be very careful of passive pre-amps they don't always play nice and it can be a real different sound many aren't familiar with. I enjoy my passive mode for some selections, but not for all.

I would take care of everything else in the chain *before* opting for a passive or line level type pre-amp. If the OP is fine with controlling the volume via the computer, I guess a pre-amp isn't needed. But that's the least "audiophile" way to do it.

Either look into getting a clean unadulturated signal out of the PC and use a nice pre-amp/amp combo or keep what you have.

To the OP, this is a very deep subject and your question while good, is very general so it's hard to give specific advice.

H9

nguyendot

hmmm. I run http://www.emu.com/products/product.asp?product=9872
EMU 1212. Think it'd be a good base?

heiney9

nguyendot wrote: »

hmmm. I run http://www.emu.com/products/product.asp?product=9872
EMU 1212. Think it'd be a good base?

I'm not going to get into what's good.....what isn't. Any internal soundcard is going to have shortcommings. You either compromise or move up the ladder. It's all about where you are in your audio journey and what your expectations are.

Not sure what you are running or what your end goals are. I am not an expert on all internal soundcards.

H9

Beerce

I realize the depth of the question, and I also know there are many different opinions regarding whether or not it makes a REAL LIFE noticeable difference between direct-sound/kmixer versus ASIO/kmapper, or whether it's just audiophiles being audiophiles.

Again, let's assume my source is not the limiting factor and then look at the original question of what you get when spending more on a preamp.

As an alternative to all of this, I could NOT buy a preamp at all, and just get a phono preamp and take that right into the input of my sound card. From here I would select the input through Windows or whichever program I'm using to play music. This would eliminate the need for a regular preamp altogether, the only pain in the arse is adjusting volume through software rather than having the convenience of a remote.

Since I'm on a budget, I will likely just pick up a lower-end preamp that already has built-in phono. I can always upgrade down the road IF I ever make enough money to afford that luxury

cokewithvanilla

nguyendot wrote: »

Can you elaborate? I'd like to give something a try if you could suggest.

thanks

If your soundcard has ASIO drivers, download them. Use a program that supports ASIO. Jriver media center does, winamp has a plugin, foobar can be configured as such.

Jriver, to me is the easiest. Set output mode to WASAPI or ASIO

keep in mind that inthe free version of jriver, after version 13 does not support ASIO/WASAPI. if you can find an older version of jriver media player, you can have it for free

heiney9

Beerce wrote: »

I realize the depth of the question, and I also know there are many different opinions regarding whether or not it makes a REAL LIFE noticeable difference between direct-sound/kmixer versus ASIO/kmapper, or whether it's just audiophiles being audiophiles.

It's not audiophiles being audiophiles.........it makes a REAL LIFE difference. Again, you're only as good as your weakest link.

H9

heiney9

Beerce wrote: »

As an alternative to all of this, I could NOT buy a preamp at all, and just get a phono preamp and take that right into the input of my sound card. From here I would select the input through Windows or whichever program I'm using to play music. This would eliminate the need for a regular preamp altogether, the only pain in the arse is adjusting volume through software rather than having the convenience of a remote.

Generally that won't sound all that great, if it works at all. Sometimes the gain out of the soundcard is too hihg or too low and many times it's very noisy. But again, I have no idea what your end goal is or how much you care about sound quality. If you are just looking to play some tunes and don't listen critically, then it might be satisfactory to you.

H9

cokewithvanilla

Beerce wrote: »

I realize the depth of the question, and I also know there are many different opinions regarding whether or not it makes a REAL LIFE noticeable difference between direct-sound/kmixer versus ASIO/kmapper, or whether it's just audiophiles being audiophiles.

Here's where I stand on that one... it costs you NOTHING to run ASIO / WASAPI.... so why the hell not?

olilugo

newrival wrote: »

for the short term:
there is no need for a preamp if you get a dac since it's line level at that point. You'll probably want to find one with a volume control built in, or an external line level volume control. In most circumstances a preamp is just a volume control and source selector (there is almost always a gain stage and buffer) and would tend to color the sound as opposed to help it. The only reason you might want a preamp is if you want to match component impedance and have an unusual mismatch like a really low amplifier or some such.

For the future:
add the pre when you get the TT. You're going to want (read: need) the DAC there even with the preamp. then look at phono stages when you get that far.

Listen to this man; he knows what he is talking about.

On the point of what makes a pre-amp worth $1000 or more vs. a $100. First you need to understand what a pre-amp is. A pre amp is almost everything that a high end receiver will be without the amp section.
The pre-amp has better components, including better dacs, transistors, and capacitors and so on.
If you think about it there are no receivers that have 500 watts amps, instead you hear of a pre-amp and then an external amp that can go anywhere from tube to solid state, from 30 watts to 1200 watts.

Consider that even when you have cd/dvd/blu ray players, tuners and others (called source), some of these sources might not have as good of a DAC as the pre-amp in which case you will set your system up so that the decoding is done by the pre-amp instead of the source.
Even then I think most importantly most of these sources even if they had a better DAC section they might not have volume control, again in this case you will need a pre-amp before the amp so that you can control the volume.

As far having a PC sound card like the one you pointed out, which has stereo out or SPDIF out. If you use SPDF then for sure you will need a pre-amp. If you use the stereo out into a stereo amp, then how long does your interconnect have to be relative to where you are sitting so that you can control the PC yet be in the right place to get the most out of your speakers?
As people pointed out there are things to consider and there are going to be some tradeoffs and some gains of-course. Good luck!
I would image that if I had a PC sound card I would probably use the SPDIF out as this is a digital connection and you can run a longer cable ? probably I have never tried it, so I would be the first one to admit I don?t really know the outcome.

Beerce

Thanks olilugo.

The cable length is definitely not of any concern. The PC will be in the same stack as the amp/preamp. All the components are on one stand so cable lengths are all very short.

If I use the digital out on the sound card as opposed to the stereo out, I will need either a standalone external DAC, or a preamp that has an appropriate DAC built-in, is this correct?

I would guess that the DAC in the sound card will be equal in quality if not higher than any DAC built-in on a preamp in my price range, so I may as well use the stereo out.

Like I said, I'm leaning towards a cheaper preamp with phono just for convenience more than anything - volume control, remote, etc.

Beerce

heiney9

Beerce wrote: »

I would guess that the DAC in the sound card will be equal in quality if not higher than any DAC built-in on a preamp in my price range, so I may as well use the stereo out.

That would be incorrect. DAC's built on/into soundcards are generally horrible if sound quality is upper most in your mind. You won't find too many pre-amps with built in dac's unless you are willing to spend a lot and, if you spend that much on a pre..........the rest of your system certainly won't being doing that expensive pre-amp any favors.

Everything matters in this hobby and you don't get something for nothing.

I am not aware of any pre-amp/dac's in your price range, but I have never looked in that price range so I may not know for sure. What are you looking to spend again?

H9

heiney9

Actaully I forgot about a whole bunch of Chinese products like:

http://www.mav-audio.com/base/archives/tag/maverick-audio

Little Dot

Grant Fidelity

Musiland

Matrix

Yulong

http://www.pacificvalve.us/DACS.html

Pacific Valve is another company that might carry something that would work for you.

and many, many more.

H9

Beerce

Heiney,

Could you explain to me, in as much depth as you feel like going into, what the primary factors are when considering a DAC and why, in general, an external DAC would be much better than for example the DAC in the Asus Xonar Essence XT.

For my knowledge. I appreciate anything I can learn here.

Also, I was looking to spend $150-250 on a used preamp. But this is only because I have yet to fully understand the benefits of a higher quality preamp. If I was convinced, I would be willing to spend more for sure

Thanks

FTGV

Beerce wrote: »

what the primary factors are when considering a DAC and why, in general, an external DAC would be much better than for example the DAC in the Asus Xonar Essence XT.

I'm not Heiney but I'll throw in my $.02.

While there are a number of very good internal SC's that should offer reasonably good results.(They basically use the same D-A convertor IC's and analog opamps as would be found in outboard DAC's.)
The biggest compromise IMO is in the very important area of the power supply(s).While the sound card will have it's own on board voltage regulators for the various digital and analog chips, the raw DC is sourced from the same supply that feeds the mother board,drives etc ,.Therefore with the PC being a hositle and noisy enviroment one would expect this supply to be less than ideal for powering high quality audio devices.

I'm of the opinion that the analog stages and the quality of the power supplies feeding them are hugely important factors in determining the sound quality of a DAC.Therefore since an external Dac has it's own dedicated power supplies the all important analog signal will not be corrupted by the PC's noisy supply .

TECHNOKID

I'm not Heiney but I'll throw in my $.02.

Maybe not but YOU are GV, the one and only GV! That should count for something, right? Don't play the modesty card with us here, OK???

OK, enough PO(L)KING at GV :biggrin: Even before I could look at your answer I had a huge hunch it would make sense, be easily and clearly expressed-understood. IMO, your explanation makes a lot of sense and should complement what Heiney has been trying to explain to the OP. I fully agree with you and IMHO this lack of proper and dedicated power supply should be enough of a reason (while not the only one) to priviledge an external DAC over a computer SC.

Also, I was looking to spend $150-250 on a used preamp.

Now, correct me if I am wrong but for $250 on the used market should be a half decent DAC not a exactly low end, right? If so, the OP should be within his budget and still acquire some of half decent quality, right?

Beerce

TECHNOKID wrote: »

Now, correct me if I am wrong but for $250 on the used market should be a half decent DAC not a exactly low end, right? If so, the OP should be within his budget and still acquire some of half decent quality, right?

I was referring to $250 on a preamp though, not just a standalone DAC. So I'm not sure if a preamp which includes a decent DAC can be had used at that price though.

I have seen some "decent" preamps in that 150-250 price range, but not all of them include a built-in DAC and the ones that do, I have no idea about their quality.

FTGV, thanks for the answer. It didn't have to be Heiney I was only referring to him because he was pointing it out
Any logical answer from anyone is always appreciated.

Ok let's have a hypothetical situation here: Let's assume the power supply on my sound card is isolated and not shared with the rest of the PC components. In this case, does the sound card become closer to the same quality as an external DAC? I suppose the answer now is that even though they share the same specs, an external DAC will likely just have better quality components and build quality?

blairfrischx

Beerce wrote: »

Ok let's have a hypothetical situation here: Let's assume the power supply on my sound card is isolated and not shared with the rest of the PC components. In this case, does the sound card become closer to the same quality as an external DAC? I suppose the answer now is that even though they share the same specs, an external DAC will likely just have better quality components and build quality?

Because of its proximity to every other thing in the computer case, an internal sound card will always be worse than a standalone DAC of comparable quality. A computer case is an incredibly hostile place (read: vibrations, EMI, general noise) for a source component to be. However, the ASUS Xonar Essence is shielded, so the gap between it and an outboard DAC should be less prominent.