question about amplifier

[TenseiRecords]

Hello, how are you? Good afternoon, I would like to know which amplifier you recommend that is valve for my cutter, I am waiting and thank you very much in advance, a cordial greeting to all.

[karl hungus]

It depends on the lathe. Stereo valve amps would be very expensive.

[TenseiRecords]

It depends on the lathe. Stereo valve amps would be very expensive.

. It is a cutter that an engineer built, inspired by a neumann vms 80, it is stereo and currently uses a generic 400w amplifier, so I wanted to improve it to a valve one, I don't know which one they recommend, and when you say expensive, what is the price,, thank you

[dmills]

Be very careful here, if it is a reasonably good copy of a VMS80, it is probably running a feedback head, in which case you really, really need the amp to have a flat frequency and phase response.

In addition the operation of the circuit breaker cards requires a small DC offset at the output of the amps to bias the detector bridge.

Finally the overall head feedback will tend to cancel the distortion from the valve amp that is the thing that gives them their sound.

If I was doing the valve thing for some reason, I would be reaching for something like a pair of external anode tetrodes (4CX250 maybe, something like that) to get that kind of power, or maybe one of those enormous ex soviet block dual triodes, maybe even a pair of 3-400Z or such, in no case will the plate voltage be reasonable or the output transformer cheap.

For a clean half kw from a valve amp I would expect to be paying a few thousand £ per channel, and it would almost certainly be a custom build because almost nobody does it that way today.

[TenseiRecords]

Be very careful here, if it is a reasonably good copy of a VMS80, it is probably running a feedback head, in which case you really, really need the amp to have a flat frequency and phase response.

In addition the operation of the circuit breaker cards requires a small DC offset at the output of the amps to bias the detector bridge.

Finally the overall head feedback will tend to cancel the distortion from the valve amp that is the thing that gives them their sound.

If I was doing the valve thing for some reason, I would be reaching for something like a pair of external anode tetrodes (4CX250 maybe, something like that) to get that kind of power, or maybe one of those enormous ex soviet block dual triodes, maybe even a pair of 3-400Z or such, in no case will the plate voltage be reasonable or the output transformer cheap.

For a clean half kw from a valve amp I would expect to be paying a few thousand £ per channel, and it would almost certainly be a custom build because almost nobody does it that way today.

I wanted to use a tube amplifier, to be able to give more color to the signal, since I don't make a direct and short master, but I cut songs that are already mastered.
Let's say that I do not use processes, so I wanted to change the amplifier for a better one, and also if you recommend something else to the chain I am open to proposals, thank you very much.

[dmills]

What does your cutting chain look like at the moment? A SAL 74 copy of some form?

Open loop you could do the valve amp thing, not really sure I would, but you could, but it will not work like you think if running a feedback head.

I could maybe see something like a vari mu desser being an interesting project, and really everything up to (and just possibly including) the feedback error amp card is a contender if you want to do the valve thing, so desser, iriaa, some head eq, feedback error amp are all reasonable things to do with glassware, but things actually inside the loop are probably better semiconductor IMHO.

Most of the 'valve sound' at least in a non guitar amp sort of context is a small signal thing, but do NOT expect this to be cheap if you do it well, the glassware is NOT cheap if you want the good stuff, and good transformers (and inductors) of which there will be many are also significantly not cheap.

[karl hungus]

I have gone with hypex 1200 based mono blocks that are solid state, and other pieces with tubes for outboard gear.
You’re going to be paying 10k+ USD for a stereo amp that has tubes and can do 8 ohms 450 watts per channel.
You probably only need 80% of those 450 watts but you need a tremendous amount of power to run moving coil heads at 8 ohms.

Feedback you have to have an amp made to accommodate and I know the amps are also about 10k.

They used tube amps because they had to but there is no reason now

[Angus McCarthy]

They used tube amps because they had to but there is no reason now

Very much this ^^^^ (says the guy operating a K8 onboard amp )

Besides, so much of the "tube/valve sound" is actually derived from the transformers in the signal chain. If you want to intentionally color the sound of your signal chain (and I'm not clear why you would really want to, besides being able to say you "have a sound") you can simply wire in a couple matching transformers ahead of your amp, and vintage ones are relatively easy to come by. All it really does is maybe add a bit of low-frequency distortion at high levels - depending on the transformer.

[Discomo]

It's a misunderstanding that tube = color and transistor = no color.
Some tube preamps (often the best) are crystal clear without any color, while some transistors (for instance Neve) give a lot of color.
Every piece of equipment does bring however it's own character. So being aware of this may be useful.