How Important Is A Pre-amp?

Im after a good pre, but wonder what is the effect it has on the overall sound?
What should you spend more on ? Pre or Power and why? Does the pre have an effect on the sound of the power or does the power have an effect on the sound of the pre? and do all power sound similar? Is a power just a dumping of the sound of the pre to the speakers or what?????confused! I recently thought that all pre amps were the same, but after listening to a few there are differences, so whats the gig? What about synergy? can you mix and match pre and powers? tubes and SS? or should they be (like mine are) the same brand?

 

I'm interested in some aspects of this post too; I was thinking of either swapping to a hybrid integrated amp (valve pre & SS power) or doing the same thing with separate pre/power....but don't know what needs to be considered when making this combination....

 

In the olden days separate preamps were a Good Thing because people had MM/MC inputs and keeping those very small voltages well separate from poweramp voltages was easier to achieve with separate boxes.

Preamps that are line-level only shouldn't be as susceptible - all you need is to be able to select one of several inputs and control the volume. Maybe some other frills. Having a line-level preamp and a power amp in separate boxes is a good way to spend more on boxes, but doesn't necessarily mean that the sound is any better. Having a separate phono stage is still good, I think.

As for synergy or mix-and-match, that comes down to the inadequacies of real-life kit - once certain electronic fundamentals are taken care of (and they usually should be - except in the case of some manufacturers who treat their pre- and power-amps as integrateds in separate boxes).

 

A pre-amp is a waste of money, either integrated amp or player with volume, will get you much more for the money, plus less cables, less trouble...

 

thanks sofar....any other offers of advice.....andy

 

I went from using my EAR 834p phono straight into my Glasshouse 300b amp, using the dact volume pot in the phono, then added a glasshouse tvc. The tvc added an ease and refinement, and seemed to give a larger scale to the sound. Imaging was improved too.
I then built the new World Designs Pre3 kit, swapping the tvc for the pre3 the increase in punch and slam in the bass was impressive. Dynamics and speed seem improved too, with no loss of detail.... all this into an amp that is an easy load, so yes, preamps will make a difference. Which you chose will be up to you and your tastes/system.... as always=)

 

Oh that that were true!

The sad fact is that CD players with variable outputs typically rely on either a digital control with it's inherent resolution losses, or a crappy passive analogue ouput stage. The end result is a loss of detail and dynamics in nearly all cases.

Integrated amps are a nice idea, but again the majority of sensibly priced ones these days are simply power amps with passive line stages tacked on.

These might well represent good value for money if you can't stretch a decent pre but experience suggests that the preamp has a very sizable effect on the voicing of a system, and active units do typically display more dynamic contrast and drive to passive alternatives - even the hip and trendy TVC. Anyone adding an M77 or Vibe Pulse2 to their setup is unlikely to agree with the poster that they are a waste of money.

 

The answer depends entirely on what power amp and sources you use.

The problem with a simple passive attenuator is that the system bandwidth will change with each setting because the attenuator forms a filter in conjunction with the drive impedance, load impedance and any capacitance on the load or cables. Transformer passives offer some benefits but remember that transformer will reflect a load between the primary and secondary windings. They can also ring at high frequencies. IME passives work well where you drive from a low source impedance of typically <50 ohm and drive a load of 100k or more via short, low capacitance cables.
You should also remember that some power amps work better when fed a tightly bandwidth limited signal and may well object to being fed HF gunk.

Active pre amps can avoid these problems but you are introducing active circuitry which may bring it's own raft of distortions and frequency aberrations.
If the active pre is of good quality I'd say it is to be preferred in most systems. They bring consistency and allow components further down the chain to work within specification.

 

By Nelson Pass here: http://www.6moons.com/audioreviews/firstwatt6/f4.html

 

I've been using a MF passive preamp for a few weeks, for reasons that are far too tedious to go into. My normal preamp is an active TEAD Vibe. To my mind, there are pluses and minuses with both approaches, and I would be reluctant to say which is 'right', or even which I ultimately prefer. Briefly, I think the passive device is more transparent and retrieves more detail, while the active device injects more pace into the music. So, it's really swings and roundabouts, but the TEAD flatters less-than-perfect recordings, whereas the MF does them no such favours.

Other postives and negatives: the MF allows much more control over volume wheras the TEAD goes from 'a bit too quiet' to 'very loud indeed' in a couple of steps on the volume. The TEAD is more versatile; it has two pre-outs and a tape-out, allowing use of a headphone amp. The MF seems to eliminate almost all background noise, whereas the TEAD, although not noisy by any means, does emit a small amount of hum.

 

mike,
a decent dac / player with volume control will do all of it's calculations at 20 / 24 bit resolution (of higher) rather than 16 it will then dither the final result so any losses are lost in the dacs noise floor. of course if you play your cd's at very low volume levels (and i mean whisper quiet) then you may get audible detail loss however in this situation just get a less sensitive amp or some attenuating cables.
i haven;t had a preamp for years now and don;t miss it in the slightest. but then i listen to that new fangled music off a hard drive so what's the point of having quality kit eh