Knight Basic Stereo 60 / KB-85 6L6GC Vintage Tube Amplifier Fully Restored
Here’s what I’ve done. 1 Installed new KTLA25 Authenticaps in the power supplies (increasing filter capacitance for better bass). 2 Upgraded the original 16uf power supply cap to a 33uf 600v solens cap. 3 The amp originally ran EL-37s, but those are out of this world expensive. So, now the amp is set up to run 6L6GCs. To do this, you must change the cathode bias resistors accordingly. I installed high quality Ohmite resistors and now the amp runs 6L6GCs at about 60% of their Max Dissipation=longer tube life. 4 Installed 100ohm screen resistors to better preserve tube life and prevent arcing at startup. 5 The original way to bias the amp required you to use a 1/4 jack connected to your multi meter. When you inserted it to test the MA, you essentially closed the circuit. I’ve installed 10ohm resistors across each jack so that when a 1/4 is inserted, the resistor sees the voltage instead of the partnering tube getting all of it. To bias the amp now, you insert a 1/4 (not connected to your multi-meter), and then measure the voltage across the resistor, and then balance the tubes accordingly. Hopefully that makes sense. It is very important that you take note of this modification before purchasing the amp. 6 Upgraded power cord, which includes a very nice Marinco connector. 7 Replaced the bias pots with high quality CTS pots. 8 All coupling caps (which the signal goes through) have been upgraded to the very, very nice (and semi-expensive) Jupiter Red Astrons. I’m a guitar player and I strongly believe in the tone of caps. These things are killers. 9 I also upgraded some other caps on the board to Obbiligato PIOs. 10 The 12AX7 sockets have been replaced with Belton 9 pins. The originals weren’t in great shape. I stripped it down and repainted it. These cages are rare FYI. That’s a long list, but pretty much, anything I replaced, I replaced with the best quality stuff I could afford. And it really shows in this amp. A Matching quad of Tung Sol 6L6GC STRs (my favorite of new production 6L6GCs). I don’t have a tube tester so I can’t test them, but I do know they have about 1000 hours on them. Should provide service for some time longer. C NOS Hammond Mullard EF86s. These should provide service for quite a big longer too. D Brand new JJ GZ34s. Couple of last notes for prospective buyers. Tube amps require love, care, and maintenance. NEVER turn the amp on before the input sourceyou risk blowing the output transformers by doing so. This amp produces significant heat and should be used in a really well ventilated area. Speaking of heat, I’ve exclusively used this thing with my variac set at 117Vs instead of the normal line (122 in my area). This is HIGHLY recommended. However, it will be in the condition I’ve described; it will be in the condition shown in the photos; it will produce sound and music; and thus it won’t be DOA. FYI, mono switch and monitor gauge button have been disconnected. Link to actual youtube video of the amp from last year. LAST NOTE: I’ve owned two Dynaco ST-70s. It maintains the tube tone, but has much better dynamics and detail. Plus, the actual circuit of the knight is much more stable, using TWO rectifiers at appropriate voltages, whereas the Dynaco destroys new production rectifiers because it just simply works them too hard. This is well documented on the forums. Photos demonstrate the physical condition. I’m in Glendale, CA 91205. The item “Knight Basic Stereo 60 / KB-85 6L6GC Vintage Tube Amplifier Fully Restored” is in sale since Tuesday, May 8, 2018. This item is in the category “Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Amplifiers & Tube Amps”. The seller is “funandfunny20″ and is located in Glendale, California. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Israel, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Colombia, Costa rica, Panama, Trinidad and tobago, Guatemala, Honduras, Jamaica.
- Type: Power Amplifier
- Brand: KNIGHT
- Model: BASIC 60
- Country/Region of Manufacture: United States
Tags: 6l6gc, amplifier, basic, fully, kb-85, knight, restored, stereo, tube, vintage