• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

7199 recommendations

Yep, these Scott's can be hummers! I got 6U8A in my LK48 and Still got a slight
hum there, I guess it's how they are.

tube
 
stoutblock said:
Well that did not work. unacceptable hum when using these tubes and adapter in both channels. Reset bias and balance with no change. let it run for 30 minutes, still hummed.

Back went in the 7199s, no hum.
Click to expand...

I suspect the adapters were too much "in the open" and were acting as an antenna for 60 HZ. The only real way of changing to the different tube is to rewire the socket. Not all that difficult really.
 
kvflyer said:
I suspect the adapters were too much "in the open" and were acting as an antenna for 60 HZ. The only real way of changing to the different tube is to rewire the socket. Not all that difficult really.
Click to expand...

I think I will just use these 7199 and keep an eye out for a new matching set...
 
stoutblock said:
I think I will just use these 7199 and keep an eye out for a new matching set...
Click to expand...

They are out there. And often, if they are testing just acceptable, not NOS, they will work quite well in the circuit. If you check with the Electronics Technicians that have done this stuff for their occupation, they will all tell you that the only accurate tube tester is the circuit for which it was designed. Even marginal output tubes can perform OK as a daily driver function.

(Yes, I know about matching PP etc.)
 
stoutblock said:
The 299c I just picked up has a couple of mismatched 7199 tubes. One is marked H.H. Scott and the other is marked Dynaco but appears to be an BP RCA. Amp sounds great but mismatched tubes always bother me. I don't have experience with the 7199 so would appreciate some input.

Thanks in advance!
Click to expand...

My suggestion is to get two of those adapters or rewire the sockets to handle the 6GH8. 7199's are hard to find and very expensive. Most American tube manufacturers of the era made these tubes. Scott actually dumped this tube in favor of the 6U8 in the 299C about mid year. My 299C uses the 6U8 and sounds great. The 7199 was supposed to be a purpose build audio tube. It was made for only a few years then no more. Sovtek made a run of pseudo 7199's but they were more like rebased 6U8's. They work, but not as well as vintage. The tube sellers I buy from have no 7199's at present. Prices for 7199's which are touted as NOS but which are most probably used testing good can range from $40.00 to $100.00. That is if you can even find a place that has any in stock. You may find some on Ebay but buyer beware! These tubes can be microphonic. Myself, I like the GE version. It sounds good and lasts.
 
seta1 said:
Prices for 7199's which are touted as NOS but which are most probably used testing good can range from $40.00 to $100.00. That is if you can even find a place that has any in stock. You may find some on Ebay but buyer beware! These tubes can be microphonic. Myself, I like the GE version. It sounds good and lasts.
Click to expand...

I found some in BT with no problem. The price was more than reasonable. :yes:


Steve
 
You must log in or register to reply here.
Back
Top Bottom