Harman Kardon Citation IV Tube Preamplifier Telefunken 12AX7

Harman Kardon Citation IV Tube Preamplifier Telefunken 12AX7 Introduction

I have owned this tube stereo preamp since about 2017 and had the power supply rebuilt in 2018, receipt of work and parts replaced in pictures below, This is a rare unit manufactured approximately early 1960's and is complete with 6 RIBBED PLATE Telefunken 12AX7 / ECC83 tubes. Most of the writing is worn off but can still read a portion of each tube. The quality tube manufacturers, and Telefunken was about the best, in the 50's and 60's didn't permanently silkscreen their info on the tubes due to other companies creating fake tubes. Telefunken used a special white paint that rubs off very easily. BUT even if there is zero writing visible they can be identified with the diamond logo formed into the base of the tube and each of these tubes have the diamond logo that has never been counterfeited. Internet lore has it the ribbed plate tubes are better than their brothers the smooth plate variety. On a Stark 9-66 tube tester a new 12ax7 tube measures at 1250/1250, these tubes measure; 1. 1000/1000 2.1050/1100 3. 825/925 4. 1100/1025 5. 975/1100 6. 1000/1000 I have used this stereo control preamplifier vary sparingly, like maybe 10 times the last 6 years. I use extremely efficient fullrange driver speakers with sensitivities over 100db and this Citation IV always had a very low level hisssss present, they probably all do but I don't know for sure. I outgrew my "cranking the stereo phase" 20 years ago and prefer to listen at low volume for the finest audio details. On regular speakers in the mid to high 80's and low to mid 90's sensitivity everything works excellent. No writing is worn off on any controls but the faceplate does have some fine scratches and a previous owner has touched up a few small spots with brown paint. Included in this sale is an original owners/assembly manual. SPECIFICATIONS: Has the same inputs as a regular/modern preamp does including phono moving magnet (MM) and also ceramic turntable input (a common needle in the 60's). It also has a "center channel output" That I have never used. Frequency response: 5Hz to 80kHz Total harmonic distortion: 0.05% Input sensitivity: 2.5mV (MM), 200mV (line) Signal to noise ratio: 85dB (line) Output: 2V (Pre out) Valve complement: 6 x ECC83/12AX7 Dimensions: 14-7/8 x 11 x 5-5/8 inches Weight: 25lbs Finish: charcoal brown and gold $1600 with tubes $1200 without tubes, or nearest offer. Will demonstrate prior to purchase. I prefer no shipping as I'd like you to ensure you are satisfied with your purchase prior to payment. SOLD AS-IS NO TRADES NO RETURNS