To pre or not to pre

[wee tee cee]

I added a pre amp to my set up yesterday and am really bamboozled by how much of a positive impact it has had sonically.
I was running a lap top based system controlling the volume with the lap top into the dac and feeding the monoblocks directly.
I thought that having less in the signal path would be best.
I was concious that digital volume on the lap top removes bits from the signal and can be detrimental but surely that cant account for the considerable improvement to what I'm hearing?
Tony.

[Ali Tait]

Weel I did say when you were across...

A pre can improve impedance matching between components, and provide gain so the amps are driven better. Can have quite an impact in a system.

Glad you are getting a big improvement mate.

[wee tee cee]

Ali,
I cant believe the difference Its made.....I thought I would just plumb it in, if its pish then just use it as a stand alone headamp set up...feck .Its majik...
Had a look at the ultra black prices.....lord help us!

[Bluedroog]

This is music to my ears. Having always used intergrated amps I was unsure on just where improvments could be made.

I've been using a Quad 909 power amp for a month or so but due to budgets am running it direct from my Beresford Caiman DAC. I plan to try out a Croft Micro 25 in March and am hoping it will take things to a new level. The Beresford does well for a budget DAC but the sound is a little flat, I'm hoping a decent pre will help in this area.

I will still have to use the digital volume on my Squeezebox Touch though as both the DAC and pre-amp don't come with a remote and I'm too lazy to get up. At some point I will upgrade the DAC to something with a remote like the new Audiolad and use the volume control on this and set the digital volume to 100%.

[DSJR]

Does the beresford have a Gator fitted? The thing is, as I understand it, is that the standard article has plenty of volts available from the op-amp, but this is attenuated down to 2V for CD standard - PLEASE correct me Stan if I'm going wrong here?

I'm sure Ali's correct about impedance mis-matching, which can make a dogs dinner of you get it wrong..

The Gator is reputedly a lower gain, but simpler (in transistor terms) and I think, a better line output buffer better able to do full justice to driving a power amp I think.

[wee tee cee]

This is music to my ears. Having always used intergrated amps I was unsure on just where improvments could be made.

I've been using a Quad 909 power amp for a month or so but due to budgets am running it direct from my Beresford Caiman DAC. I plan to try out a Croft Micro 25 in March and am hoping it will take things to a new level. The Beresford does well for a budget DAC but the sound is a little flat, I'm hoping a decent pre will help in this area.

I will still have to use the digital volume on my Squeezebox Touch though as both the DAC and pre-amp don't come with a remote and I'm too lazy to get up. At some point I will upgrade the DAC to something with a remote like the new Audiolad and use the volume control on this and set the digital volume to 100%.Christian,
You're ears are not deceiving you. The caiman is a good bit of kit but flat as a pancake sonically as a pre...mighty fine for the money though....

[sq225917]

Controlling the volume on the pc before it feeds a dac is a recipe for disaster, even with a decent software volume control, ie 24 bit dithered, which many still aren't. That sadi your dac needs to be up to the task of driving your power amps direct, and many are not, even if they claim to be so. If your dac doesn't have it's own volume control then you can reasonably safely assume it's not pre-amp standard.

[Bluedroog]

Hi Simon, unless I've missed something looking at your kit list am I correct in thinking you're using the M-DAC as a pre? How do you think it performs next to a dedicated unit? On my wish list I've a Croft Micro 25 and the Audiolab M-DAC, do you think adding the Croft to the chain will be a worth while exercise? And where do you think I would get greater gains? (Assuming I go for both which to get first for best short term gain given similar price).

Generally I am looking at the long term gains but currently because I'm in between a series of upgrades I've actually found myself in a situation where I've upgraded but my system has overall taken a step back. My Quad 909 is a much better amp than that of the one it has replaced (Arcam Alpha 8) but having an inadequate pre section is letting the side down. As Tony has confirmed it's just sounding a bit flat, I know (although far from complete, is it ever?) my system has a lot more to give and I think a DAC with a better pre section or dedicated pre will help realise that. Not knocking the Caiman (no Gator by the way Dave) as a DAC at all as via my integrated it sounded great.

I will either upgrade my Caiman to the M-DAC or add the Croft around March and then my system will have to stay like that for quite a while (about year) due to other financial priorities. While long term is always my main aim given the 12 months I want to make the most of the next purchase for what it is too.

[wee tee cee]

Christian,
For the kind of money you're talking about I can Highly recommend the musical fidelity m1 dac and m1 hpa.
I have been using the dac for over a year and have yet to hear anything that betters it significantly. The headphone amp can be used as a single input pre and has really surprised me in its ability.
The schiiit dac and head phone amps are also getting great ink.I believe one of the head amps can be used as a pre.
Tony.

[wee tee cee]

the schiit lyr looks like it can be used as a pre.

[sq225917]

Christian, I do use the pre-amp functionality on the MDac, it sounds pretty good, certainly more lively than my B1 was, but it is only useful if you are using just digital sources. I don't know the Croft but I would imagine it would sound different to the MDac, different maybe not better as that's a qualitative judgement.

The Mdac and 909 should sound better than the Arcam for sure...much

[realysm42]

Sorry to hijack, but what's the idea behind a pre-amp please?

[sq225917]

To alter the signal from a source component such that it is most suitable for driving power amp/s. Typically this can include amplifying or attenuating the signal and generally some form of impedance correction for driving the load of the power amp/s without frequency dependent attenuation arising from an impedance mismatch.

[Reid Malenfant]

Sorry to hijack, but what's the idea behind a pre-amp please?
Switching for different inputs (usually)

Volume control (always).

Channel balance (not always).

Phono amp & RIAA equalisation (sometimes).

Buffered line output for recording (sometimes).

Impedance matching between input to output (mostly).


It's a whole lot easier to get these things with a standard pre amplifier, though they are not known as active - just a pre amp. With a passive pre amp there is no active powered circuitry at all in the line of the signal so it's a tad more difficult to do most of the above.

In simple terms a pre amp boosts the signal & controls the volume level being fed to a power amp :)

[realysm42]

Cheers; so if you were to have a 'typical' intergrated amp, would there be any benefit in adding a preamp to the mix (bit of an open question I know)?

[Reid Malenfant]

No, think of the word "integrated", basically an integrated is both pre & power amps in a single case ;)

[realysm42]

No, think of the word "integrated", basically an integrated is both pre & power amps in a single case ;)

Yeah (I don't mean to sound indignant but I know that much), I was just wondering once you've "bought into" that path (intergrated) are you stuck on it until you get a pre and power combo, or is there benefit to using say an M-dac as your pre amp?

Sorry I'll stop derailing the thread now :)

[Reid Malenfant]

It depends on if the integrated amp in question happens to have a set of phono sockets on the rear labelled "pre out" & "main in", in which case you could totally bypass the pre amp section. Or for that matter just use it as a pre amp & feed an external power amp, or bi amp if you wanted etc, etc :)

[realysm42]

Yeah I read there's a power version of the Caspian M2 coming out and it said you can use the original (intergrated version) as a pre amp. Wouldn't that make it a grossly over priced pre amp? Surely a lot of what you've paid for would be sat redundant?

[Reid Malenfant]

Ah, but you'd have a pre amp with a humungous PSU & there is no bad thing in that :) For starters there would only be quiescent current loading on the PSU from the power amp section which would seriously reduce PSU ripple voltage which would quite probably improve the sound of the pre amp section :D

[Jonboy]

Christian,
You're ears are not deceiving you. The caiman is a good bit of kit but flat as a pancake sonically as a pre...mighty fine for the money though....

Glad it's not only me who thinks that, (sorry Stan) perhaps the pot is to blame

[realysm42]

Ah, but you'd have a pre amp with a humungous PSU & there is no bad thing in that :) For starters there would only be quiescent current loading on the PSU from the power amp section which would seriously reduce PSU ripple voltage which would quite probably improve the sound of the pre amp section :D

Okay, there's a massive risk I'm about to speak out of my derriere, but features of the amp (from the website) are:

*Independent Analogue Output stage Power Supply

*Independent Preamplifier stage Power Supply

Is that something akin to being a pre-amp already?

I'll chuck this bit in as well because I know you'll undertsand it lol:

*350VA ultra low noise, Power section Toroidal transformer

*60VA ultra low noise, Pre section Toroidal transformer

[Reid Malenfant]

Hmm, with independant PSU transformers there would be less of an advantage to what I outlined in my previous post. It looks like they are more geared to bi-amping or even tri-amping or going fully active :eyebrows:

[realysm42]

What does fully active mean please?

I thought "active" in this sort of context meant that a monitor speaker has it's own amp?

[Reid Malenfant]

It means you'd feed the output of the pre amp to an electronic crossover & the crossover outputs to however many power amps would be needed to drive each driver individually. Obviously the internal passive crossover in the speaker would need to be bypassed or removed.

Which is what I have in my case ;) Pre amp to 2 x Behringer DCX2496 digital crossovers set to mono 4 way & driving 8 channels of power amplification :eyebrows:

Admittedly most active speakers have the crossover & amplification built in as you pointed out. Nothing to stop it being external though...

[realysm42]

It means you'd feed the output of the pre amp to an electronic crossover & the crossover outputs to however many power amps would be needed to drive each driver individually. Obviously the internal passive crossover in the speaker would need to be bypassed or removed.

Which is what I have in my case ;) Pre amp to 2 x Behringer DCX2496 digital crossovers set to mono 4 way & driving 8 channels of power amplification :eyebrows:

Admittedly most active speakers have the crossover & amplification built in as you pointed out. Nothing to stop it being external though...

Christ :eyebrows:

So if you had 2x 2 way speakers and the bespoke crossover allocating an amp to each part, you'd need four amps to drive the two speakers?

[Reid Malenfant]

Christ :eyebrows:

So if you had 2x 2 way speakers and the bespoke crossover allocating an amp to each part, you'd need four amps to drive the two speakers?
Or a pair of stereo power amps, or once again a multichannel (5 or 6 channel) power amp such as used in cinema setups with not all channels used.


Even I'm getting conscious of thread crapping now :o

[The Grand Wazoo]

Christ :eyebrows:

So if you had 2x 2 way speakers and the bespoke crossover allocating an amp to each part, you'd need four amps to drive the two speakers?

Martin,
Take a look in the AoS Library, there's a rather good explanatory article (http://theartofsound.net/forum/showthread.php?t=5818) in there about many of the different ways to wire up speakers with one or more amps (both actively & passively).

[realysm42]

Thanks, I actually read that a while ago and forgot a lot of it. Using this thread to apply as context, it makes a lot more sense to me.

[Gazjam]

What Preamp have you got Tony?

[wee tee cee]

Gary,
I'm using the musical fidelity m1 hpa. Bought it as a head amp but it has a few tricks up its sleeve, flexibility wise. The positive sonic difference it has made has not been subtle.
Tony.

[wee tee cee]

Funnily enough, chopped the 5i in against it.

[Gazjam]

yeah.. :)

[realysm42]

It depends on if the integrated amp in question happens to have a set of phono sockets on the rear labelled "pre out" & "main in", in which case you could totally bypass the pre amp section. Or for that matter just use it as a pre amp & feed an external power amp, or bi amp if you wanted etc, etc :)

Mark mate, I'd kinda forgotten about all of this until today; I've got a pre-output section (one set is for my sub) and pre input section (all RCA, except for one set of xlrs, which is what I'm using).

I don't have anything called main in; does this mean it's not an option for me?

You can tell the Mdac to be a pre amp or turn it's volume off, I've had it off for months, I don't see any advantage in having it on in my current setup?