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ST-120 tube set

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Greetings everyone. This is my first post on this forum. I have found it very helpful and I appreciate all of the great information.

I am new to the tube world, and I plan to build my first amp. I have done a bit of research - the information out there is a but daunting to a beginner - and I have decided to build the ST-120 kit from Bob Latino. I have spoken to Bob and exchanged a few emails and I feel comfortable that this is a good starting point.

Where I am most confused, is with the multitude of options for various tubes, both the type, and even among different manufacturers of the same type, for rectifier, driver, and output tubes.

I am looking for some thoughts on various tube options. I have seen many posts that discuss options for specific functions, such as output, rectifier, etc. But it is hard to tell whether these tradeoffs are specific to a certain amp, or whether for example, a certain output tube works better with a given driver tube. So I am trying to view this as more of a package.

Bob has a standard set of tubes that can be ordered with the set, which include Sovtek 6550 output tubes, 3 X USA made 5963 driver tubes and a 5AR4 rectifier. I have no doubt that this would be a good starter set.

However, I am pretty sure that there are other opinions out there, and I am curious to know what people think.

My objectives are to use this either in my family room/dining area/living room which is a fairly open floor plan and about 24' square (give or take), or in the master bedroom, about 18 X 24.

My listening habits are usually classic rock, 60s rock, and classical.

I am not a highly critical listener, so I am not looking for perfection. The (approximately) $200 for the set available with the kit seems to be a good budget. I am willing to go a bit higher, but I am not looking to spend several hundreds of dollars on tubes - at least not yet.

Thanks for any advice from forum members.
 
I would also say to go with Bob's set of tubes. Hopefully the 5AR4 in not a Chinese JJ brand. I personally have no experience with, or use for, Chinese tubes. But I have read several times on this forum that they are poorly made and will probably not last long. Maybe contact Bob and see if he does, or can, supply Russian 5AR4s which should be much better. NOS 5AR4s (American & European) are the best but have become coveted and too astronomical in price.
 
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When I built Bob's ST-70 clone several years ago it was supplied with a Chinese 5AR4, but I can't recall which brand. What I do remember was its spectacular demise when I accidentally hot-switched it. The Sovtek replacement I purchased for $12.50 has been chugging along ever since.
 
There is fellow over at AK (Audiokarma) and others , that like Tungsol KT-120's on his and recommends them for a sonic improvement, for not too much more $. They should last longer also the way they they are run in that amp compared to 6550/KT-88 types as they are sort of a HD version of those tubes.

Jim McShane of McShane Tubes would be a great source for those as he tests and matches tubes to the proper degree.

The diode Mod posted on the tubes4hifi (Bob Latio's) site Forum will help the rectifier tube last using UF4007's as an upgrade over the IN4007's as they are a newer, quieter, & faster SS diode for a few cents more each.
 
There is fellow over at AK (Audiokarma) and others , that like Tungsol KT-120's (Output Tubes) on his and recommends them for a sonic improvement, for not too much more $. They should last longer also the way they they are run in that amp compared to 6550/KT-88 types as they are sort of a HD version of those tubes.

Jim McShane of McShane Tubes would be a great source for those as he tests and matches tubes to the proper degree.

The diode Mod posted on the tubes4hifi (Bob Latio's) site Forum will help the rectifier tube last using UF4007's as an upgrade over the IN4007's as they are a newer, quieter, & faster SS diode for a few cents more each.

Also besides never hot switching a tube amp , never run it without a load (speakers or big resistors if testing) or you risk the output transformers.
 
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