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Anyone use ICs as input phase splitters for tube equipment

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Hi,

I imagine that it would not be so easy to use an IC as phase splitter as the grid voltage swing needed by most output tubes is quite high and most opamp IC's can only handle +/- 18V. it would be possible to make a discrete input stage with transistors without any problem but I cant really understand why someone want to do that.

I have never heard a hybrid amplifier of any kind that sounded as good as a good all tube amp so I personally stay away from hybrids. I am quite sure that I know some of the reasons why hybrids sound doesn't sound as good but it would take too long time to explain that here.

Regards Hans
 
zobsky said:
Tending towards the jensen transformers for this duty but before i make the plunge, i was curious about SS alternatives and their effect (or not) on the performance / sound in tube push pull circuits


this is at the input, so voltage swing at the output is not necesarily a big factor

Assuming you mean in front of a balanced tube stage, if your source is CD, you are just adding 1 more chip after the chips in the DAC before it hits the tubes, so how bad can it be? And, people have posted here that the DRV134 gives good sound even in front of discrete amps.

But I'm not a tubie at the moment, so I can't speak from experience.
 
tubetvr said:
Hi,

I imagine that it would not be so easy to use an IC as phase splitter as the grid voltage swing needed by most output tubes is quite high and most opamp IC's can only handle +/- 18V. it would be possible to make a discrete input stage with transistors without any problem but I cant really understand why someone want to do that.


Regards Hans

No, .. I was raising the possibility of using the opamp as a phase splitter at the INPUT, ... before either the driver or the power stages , ..just looking for opinions
 
No, .. I was raising the possibility of using the opamp as a phase splitter at the INPUT, ... before either the driver or the power stages , ..just looking for opinions

OK, I understand and it has been done that way but I personally believe it doesn't have any advantages over a all tube solution IMHO.

I dont know if I should touch this subject or not as I am bound to get a lot of feedback of opposite opinions but I dont believe in interstage transformers either, I prefer to use tube based phase splitters, most preferably the split load type that I have found to be the best in most cases.

Regards Hans
 
Ex-Moderator
Joined 2003
It just so happens...

I've just fired up a hybrid power amplifier with a JFET in the input stage. To my ears, it has a slight semiconductor sheen, but it's not bad at all. I have to say, though, that the (measured) distortion would have been lower if I could have used a valve at the input stage.

However, I think your question is more fundamental. A transformer can do a great deal more than simply phase splitting. It can also break earth loops and reject common-mode noise. You need a really good reason to mix semiconductors with valves.
 
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