[GWorlDofSPACE]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif As someone who was going to watch this thread out of curiosity to hopefully see something designed and learn from that process, it is a little sad it might not go anywhere. The problem seems to people seem to be ignoring the info given by the O/P. A project like this needs someone to set out some constraints to focus things. If you check the O/Ps posts, First : 100% tube Second: target phones were HD800 and T1 so forget the Grados and other low impedance. Third: State of the Art Fourth: "reference" So my comments on those points: 100% tube - not having built any tube gear myself, running an amp that is all tube would be cool. I could expand this to say OTL with no caps in the path (as caps in the path would not be 100% tube) Reference - an interesting definition. Does that mean reference in the way that many call the beta22 a "reference amp"? Or could it mean the way the SSMH is a "reference" point for a "tube-y" inexpensive amp? or "reference" for easy to build tube amp? or .... Headphone target - could be debated until the cows come home if the O/P is right in his choice, but it doesn't matter - that his choice and his target, and I could say mine owning HD650's. So the next unknown limit was price. Was it $10K or $200? Having a design that no-one can build because they can't afford is useless. So let me throw an idea out there that all of you can all ignore if you'd like: I'd assert that the SSMH is a "reference" design for a simple hybrid tube amp that sounds good. Can someone come up with the all tube equivalent to drive high impedance (300Ohm) phones? May have been a threadjack, but hopefully this gets this thing going again.

You can not create perfection because there are always limitations. A state of the art amp is something so good that is exceptional on its kind. Maybe we should think about a reference project at first.
-budget should be maximal 1K!!!
-about the question if transformer output or OTL, why not make it possible to apply both!! (you can choose)
-I think whit both topologies you can drive low and high impedances very well.
-single ended and also balanced if needed
-if possible no hybrid

What you think?

 

[cobaltmute]

Quote:

Originally Posted by GWorlDofSPACE /img/forum/go_quote.gif -budget should be maximal 1K!!! -about the question if transformer output or OTL, why not make it possible to apply both!! (you can choose) -I think whit both topologies you can drive low and high impedances very well. -single ended and also balanced if needed -OTL no capacitors in the signal path -if possible no hybrid What you think?

To me this is starting to look like the list of requirements. But you say OTL or transformer and then OTL only. Think you need to make a choice choice there

 

[GWorlDofSPACE]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif To me this is starting to look like the list of requirements. But you say OTL or transformer and then OTL only. Think you need to make a choice choice there

I made a mistake! As I said the best would be to apply both of the worlds or at least to be able to choose!!!

 

[Parafeed]

Quote:

Originally Posted by GWorlDofSPACE /img/forum/go_quote.gif As I said the best would be to apply both of the worlds or at least to be able to choose!!!

There isn't a one size fits all. 2 different sets of design requirements == 2 different designs. It isn't a case of designing a single circuit, then adding an optional output transformer for those who want it.

 

[GWorlDofSPACE]

Quote:

Originally Posted by Parafeed /img/forum/go_quote.gif There isn't a one size fits all. 2 different sets of design requirements == 2 different designs. It isn't a case of designing a single circuit, then adding an optional output transformer for those who want it.

I am aware of that. But it looks like we can not decide in which way to go. What would you prefer? Say we are looking for a dynamic-life-like total organic sound but also very detailed.

 

[cobaltmute]

Quote:

Originally Posted by GWorlDofSPACE /img/forum/go_quote.gif I am aware of that. But it looks like we can not decide in which way to go. What would you prefer? Say we are looking for a dynamic-life-like total organic sound but also very detailed.

I think that is a question you need to answer - you've stated 100% tube. Does that mean a transformer in the path or not?

 

[GWorlDofSPACE]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif I think that is a question you need to answer - you've stated 100% tube. Does that mean a transformer in the path or not?

Yes, why not? We will get stuck if we go so on. Please a few posts ago I wrote some guiding lines and everything else is open.

 

[TimJo]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif As someone who was going to watch this thread out of curiosity to hopefully see something designed and learn from that process, it is a little sad it might not go anywhere.

It's too bad it seems to have crashed.

I was actually looking forward to watching an evolution of a design, especially with Alex involved, because he is great at explaining the tradeoff's in making design decisions.

 

[luvdunhill]

The stark reality is that anything that will be considered state of the art won't be designed by the collective minds on this website. The two salient points in that statement being "this website" and "collective minds".

 

[TimJo]

Quote:

Originally Posted by luvdunhill /img/forum/go_quote.gif The stark reality is that anything that will be considered state of the art won't be designed by the collective minds on this website. The two salient points in that statement being "this website" and "collective minds".

Your probably right. But I would say the evolution of the eXStatA proved something can be done on this website - so it may be the collective minds are the real stumbling block here...

 

[Parafeed]

State of the art, is the stumbling block. Getting two people to agree on what is state of the art is asking too much.

 

[GWorlDofSPACE]

Quote:

Originally Posted by Parafeed /img/forum/go_quote.gif State of the art, is the stumbling block. Getting two people to agree on what is state of the art is asking too much.

Do not bother whit that, would a word named reference make any difference?
Once again I am asking you what do you prefer OTL or OT? What would you choose for a reference project ?

 

[nikongod]

Quote:

Originally Posted by GWorlDofSPACE /img/forum/go_quote.gif Once again I am asking you what do you prefer OTL or OT? What would you choose for a reference project ?

Why does it matter what other people prefer? You are the only person who needs to be happy with your amp(s).

How much research have you done for yourself on this? Have you gone out and listened to these various topologies? Have you tried something with SS parts laced in with the tubes to see if you like that? Have you compared OTL and TC amps in even a broad & sweeping fashion.

 

[GWorlDofSPACE]

Quote:

Originally Posted by nikongod /img/forum/go_quote.gif Why does it matter what other people prefer? You are the only person who needs to be happy with your amp(s). How much research have you done for yourself on this? Have you gone out and listened to these various topologies? Have you tried something with SS parts laced in with the tubes to see if you like that? Have you compared OTL and TC amps in even a broad & sweeping fashion.

In this thread I wanted to get answers to such questions. It should be a community project, where everyone has a right to ask what every he wants.
You know that clear answers if OT or OTL cant be made. So its important that many people say something about it. If I had some much experience in this topic I would build one of my own pal!

 

[Parafeed]

Quote:

Originally Posted by GWorlDofSPACE /img/forum/go_quote.gif You know that clear answers if OT or OTL cant be made. So its important that many people say something about it. If I had some much experience in this topic I would build one of my own pal!

Nikongod has a point. Your preferences are what matter, not ours. I already stated a preference for transformer designs. With a $1K budget both an OTL or transformer amp can be designed. Whether anything is designed as a collective or not, your preferences should guide you. Have you heard a single-ended transformer (plate) coupled amp without feedback? Have you heard something like the MAD EAR+, a single-ended transformer coupled amp, but the transformer output is coupled to the cathode of the output tube, instead of the anode - cathode follower transformer output? Do you have preferences on feedback? Global feedback is a complete no-no? You don't like the sound from cathode followers? You'd rather not have more than 6db of global feedback, otherwise you feel that you might as well switch to a cathode follower output and have 100% local feedback rather than 20db global feedback?

The point is, I can tell you what I like and dislike, what I think is the best way to go, but your ears are what matters, not mine. Before putting a grand on the table to buy the parts on a list, I'd like to have some idea if a finished design is going to suit my preferences. You should too.