Audio Asylum Thread Printer
Get a view of an entire thread on one page
|For Sale Ads|
I have an AES Super Amp MKII (Audio Electronics, a division of Cary Audio) on my bench for service. It needed output tubes. Anyone familiar with this amp knows how versatile it is. It can employ EL34, 6550, KT 77/88 et el. This one happened to have KT77, which I stuck with. Now I need to set the bias. I've worked on Cary before, so I have the bias jig, but the other Cary I serviced had a 1/4" jack and adjusting pot for each channel, this only has one. In addition, I don't know what the setting should be. Does anyone have a owners manual or service manual. Just the page that speaks to bias setting will suffice.
I have the original version....not sure how it differs from the Mark 2. Bias on my amp is for all 4 tubes (275 - 285 mA's). Dennis Had told me to use a decently matched quad of output tubes as there is no individual (or paired) adjustment. Don't know if this helps any as the test points are rather meaningless without a diagram, but unfortunately there is no master diagram -- the points referred to are shown on each assembly page separately.
Thanks for your quick reply "B". Fortunately it only needed output tubes.
My Super Amp doesn't have the UL/triode switch. Maybe that's the difference with the MKII. The original version is such a killer little amp for the money it didn't need messed with. :)
If yes, you can use the recommendations for an el34 to start with. If a push pull amp you can start with something like an EICO HF89 which is set at 63ma for 2 tubes, if my memory is correct.
You should install 10ohm current sensing resistors on the power tube cathodes to find what the idle current is if your amp doesnt have them.
Post a Message!
This post is made possible by the generous support of people like you and our sponsors: