Valve versus SS preamp stage

[Count Bassy]

I have a Marshall MB150 combo (150W 15" speaker, no tweeter) which has both Solid State and Valve pre amps, with the ability to blend between the two.

The thing is though, I really can't hear that much difference between the two. Yes there is a difference, particularly if you overdrive it - the valve distorts more gently, but if your not overdriving it the difference is minor compared to what can be obtained with the various eq settings (this combo has bass, treble and a a 7 band equalizer, along with Bright and Deep buttons).

SO:

[list]
[*]Am I just cloth eared?
[*]Is this combo just a bad example of a valve preamp/ good example of a SS preamp?
[*]Is this particular combo design just not able to show the difference?
[*]Could it just be that the the valve in the preamp is shagged?
[*]Is the whole thing about the 'Valve sound' just over stated and the same affect can be acheived through a modern Eq circuit?
[*]Would a different brand valve in the pre-amp make a more marked difference?
[*]are there other factors that I've not thought of?
[/list]

Please let's try not to make this a slanging match about Marshall, or a protracted argument about Valve versus Solid State. - I'm looking for answers rather than an argument.

Many thanks for your thoughts.

Edited May 23, 2009 by Clive Thorne

[Musicman20]

I think unless you go full on all tube there isnt a massive difference. It can add some grit and usually warmth to have that tube pre-amp. This is my experience anyway. My old Trace had a similar setup...and I just had the tube setting on full...not sure if its exactly the same kinda thing...but it wasnt a huge difference in tone.

Then I tried a full on tube amp...and all was different!

[maxrossell]

In my experience, both with Marshall amps and in general, the difference a preamp valve makes is minimal when it's going into a SS power amp.

A constant pretty much across the board these days is that the majority of the time, a single valve wedged into an otherwise solid-state setup is not much more than a selling point, and rarely presents quantifiable advantages over an all-SS rig. At most there might be some colouration of the sound, some more perceived warmth, but a lot of the time this is actually to do with EQ presets that favour that impression, of the variety you get on SS amps that only simulate valve sound.

The "valve sound" that most people refer to in terms of amplification has in my experience a lot more to do with power section valves than it does with preamp valves, which are generally more to do with gain ratios than overall tone.

[Monz]

I have just moved my Markbass on and got a Mesa Boogie all valve combo...

I tried all manner of valve preamps in front of the Markbass and some were ok allthough like you say the difference is small, then I tried an all valve 400W amp and the difference to my ears was like chalk and cheese in fact it was about the same difference as going from a cheap and cheerfull bass to the Stingray 5 in terms of definition and tone.

I can't see me ever going back to SS unless my back breaks

Hope this is of some help

[bozzbass]

i'd agree with maxrossell regarding the majority of 'tube tone' being in the power amp. I tried an old Simms Watts head recently that had a SS pre going into a tube power section and it was tube tone ahoy, really dynamic and big.

The old music man heads had a similar setup, SS pre into Tube power, worth checking out.

I too hear little difference when tweaking the blend on an amp that has SS and tube pre sections and it has been said to me before that a solitary tube located on an SS board is little more than an orange glow to look at.

Edited May 23, 2009 by bozzbass

[wateroftyne]

I've had a similar thing with hybrid heads in the past. My SVT Pro3 had a blend knob, and it made no discernable difference.

That's part of the reason I moved to Mesa stuff... the Simulstate design really does introduce tubiness to the tone, like the DB750 and the Warwick Tubepath.

[Musicman20]

[quote name='wateroftyne' post='495995' date='May 23 2009, 12:56 PM']I've had a similar thing with hybrid heads in the past. My SVT Pro3 had a blend knob, and it made no discernable difference.

That's part of the reason I moved to Mesa stuff... the Simulstate design really does introduce tubiness to the tone, like the DB750 and the Warwick Tubepath.[/quote]

Completely agree on this about the Pro 3. I had people trying to sell me it in shops instead of a full tube amp. The SVT 3 Pro is a good head, but sometimes lacks the volume and the tubes seem to do very little.

Best bet is to have a lightweight SS amp.....and a normal weight full tube amp Best of both worlds!

[Monz]

[quote name='Musicman20' post='496011' date='May 23 2009, 01:16 PM']Completely agree on this about the Pro 3. I had people trying to sell me it in shops instead of a full tube amp. The SVT 3 Pro is a good head, but sometimes lacks the volume and the tubes seem to do very little.

Best bet is to have a lightweight SS amp.....and a normal weight full tube amp Best of both worlds![/quote]


You is obviously consinderably richer than me

[Musicman20]

[quote name='Monz' post='496019' date='May 23 2009, 01:25 PM']You is obviously consinderably richer than me [/quote]

I wish haha!

Just spending all available money on bass gear before I move/buy a house.

I was going to settle for just one good tube amp...but the Markbass stuff lured me in! Now ive got to choose which one!

[Delberthot]

I really believe that it all boils down to what you've got:

Gallien Krueger - solid state but does a good impression of a driven valve amp
Ashdown - Valve pre - as wooly as a wooly christmas jumper
Hartke - pass

Genz Shuttle - personally this is the best sounding light weight amp I've tried. I could even be persuaded to say better than Gallien in overall sound. The valve does make a huge difference to the sound as far as I'm concerned.

I recently had the misfortune to try an Ampeg STV II Pro and, well, it was complete $h!te. Definitely put me off valve for a while. It'll take someone a lot of effort and a warm Marshall VBA400 to change my mind. I used the Shuttle in preference to it as it sounded a million times better and louder.

I've just recently sold a proper valve preamp combo - a Trace Elliot TVT9 guitar combo - it had 8 preamp valves which were very effective. there is a debate as to whether 1 single preamp valve does anything or not. I'm looking into multi valve preamp setups just now

Edited May 23, 2009 by Delberthot

[Count Bassy]

So to summarise, the general feeling is that valve pre-amp into SS power stage is a waste of time (I guess that must go for the valve powered effects units as well then). So if I'm sticking with SS amps then I'd be better off looking for a good flexible equalisation section.

Thanks for your thoughts.

[alexclaber]

[quote name='Clive Thorne' post='496898' date='May 24 2009, 10:51 PM']So to summarise, the general feeling is that valve pre-amp into SS power stage is a waste of time (I guess that must go for the valve powered effects units as well then).[/quote]

No, it totally depends on the individual components. Some valve preamps sound amazing and valvey, some sound amazing but not in a valvey way, and some sound mediocre. Just like generalising on tone based on speaker diameter leads you to often incorrect conclusions, so does generalising based on amp topology.

Alex

[Sjonnie]

[quote name='alexclaber' post='497926' date='May 26 2009, 01:42 PM']No, it totally depends on the individual components. Some valve preamps sound amazing and valvey, some sound amazing but not in a valvey way, and some sound mediocre. Just like generalising on tone based on speaker diameter leads you to often incorrect conclusions, so does generalising based on amp topology.

Alex[/quote]

Fully agree. I have a number of preamps myself, such as a Glockenklang that is completely solid state and a Hevos that containes two valves. The differences between these preamps are very subtle.

[Machines]

Are we overlooking the variable that is which valve you put into the preamp ? I've changed the valve in my ABM from a standard 12AX7 to a GT one (can't remember exact model) and it was very different.

[DirkThrust]

[quote name='Machines' post='499566' date='May 28 2009, 08:01 AM']Are we overlooking the variable that is which valve you put into the preamp ? I've changed the valve in my ABM from a standard 12AX7 to a GT one (can't remember exact model) and it was very different.[/quote]

What difference did that make? I find the valve in my ABM goes from having not a lot of effect to full on farty distortion within about an eigth of a turn of the level control, and I've been thinking about changing it to get a more gradual breakup.

It's an Electro Harmonix 12AX7 at the moment

Edited May 28, 2009 by AndyMartin

[henry norton]

Thing is, most all valve amps have 3 or 4 valves in the pre section (in my experience), yet most of these 'valve preamp SS power amp' types only have one, so there's far more SS than valve in the pre. That asides, the general consensus seems to be the distortion/colouration you get from a valve power amp is much more pleasant than that of a valve pre - even a proper one. I think the Genz Shuttle sounds good because it was designed by someone who actually understands how to make a bass amplifier sound good. I'm pretty sure there are still quite a few amps out there that aren't.

Just my humble opinions of course - I use an all valve combo 'cos I like the look and the smell as much as the sound....

[chris_b]

In defence of the Ampeg SVT 3 PRO; I've had mine for 10 years and it's never sounded anything but great. I don't know which part, pre or power, is responsible for the sound but it's loud with a huge tone and it's still got the stock valves, whatever they are!

[rmorris]

[quote name='alexclaber' post='497926' date='May 26 2009, 12:42 PM']No, it totally depends on the individual components. Some valve preamps sound amazing and valvey, some sound amazing but not in a valvey way, and some sound mediocre. Just like generalising on tone based on speaker diameter leads you to often incorrect conclusions, so does generalising based on amp topology.

Alex[/quote]

+1

A valve stage can be pretty much as clean as a transistor / opamp stage if not driven into non-linearity - depending on the design and toplogy - class A ; AB etc.
Some real electronic engineering knowledge helps but basically listen carefully and trust your ears - then go for what you like.

[Buzz]

[quote name='AndyMartin' post='499573' date='May 28 2009, 08:13 AM']What difference did that make? I find the valve in my ABM goes from having not a lot of effect to full on farty distortion within about an eigth of a turn of the level control, and I've been thinking about changing it to get a more gradual breakup.

It's an Electro Harmonix 12AX7 at the moment[/quote]

Chances are you'll want a lower gain tube, as the 12AX7 (aka, ECC83) has a gain factor of 100, look for a 12AT7 (ECC81) which has a gain of around 60.

Also, as it's about time it gets pimped on here again after certain childish incidents caused it's disappearance:

[b][url="http://finnbass.com/showthread.php?t=22"]http://finnbass.com/showthread.php?t=22[/url][/b]

Bryceee's Pre-amp (and all round) Valve Comparison thread. It's awesome. Go read. That applies to everyone!

Edited June 2, 2009 by Buzz

[Count Bassy]

[quote name='alexclaber' post='497926' date='May 26 2009, 12:42 PM']No, it totally depends on the individual components. Some valve preamps sound amazing and valvey, some sound amazing but not in a valvey way, and some sound mediocre. Just like generalising on tone based on speaker diameter leads you to often incorrect conclusions, so does generalising based on amp topology.

Alex[/quote]


Ah, the thread has come back to life.


Alex, When I wrote what I thought was a concluding summary (as the thread seemed to have dried up) what I said seemed to be the overriding view of the posts up to that point. I wasn't expressing my own opinion as I don't have one - hence the questions in the original post!

Since my premature summary the weight of opinion seems to be going back towards yes the valve should make a difference but it depends on the valve (and other factors).

I believe that the valve in the Marshall B150 is a 12AX7. Assuming that it's still the original valve can anyone suggest an alternative valve to try, something that might make the difference between the valve and the SS pre-amps a bit more noticable/useful.

I get the impression from the above that the difference is most noticable when going into distortion, is this correct?

Thanks again for your thoughts folks.