KENWOOD KA-7100 INTEGRATED AMPLIFIER

Up for your Consideration is a Comprehensively Restored Kenwood KA-7100 integrated amplifier.

This gorgeous classic and powerful unit is always at the top of our clients “most requested ready to go units”. Due to our restoration backlog and the amount of work that goes into a proper comprehensive restoration of a 7100 we are only able to offer these from time to time as ready to go units, Numerous upgrades and extensive enhancements have been performed on this unit to elevate it into a new level of High Fidelity unit is in overall excellent vintage condition with the normal wear and tear expect from a vintage unit from the 70s more pictures available on request.

Details of Restoration:

1. Full electrolytic capacitor replacement using Nichicon Muse and Vishay power supply capacitors.

2. Any electrolytic capacitors rated at 10uf or less has been replaced with a Wima film capacitors.

3. All known noisy transistors have been replaced with modern OnSemi high quality replacements and Hfe matched.

4. The Dual Power supply / protection circuit board has been completely rebuilt from scratch with higher voltage Vishay power supply capacitors, every single resistor was replaced with high quality Vishay metal film military grade higher wattage resistors. Regulator Transistors were replaced with modern, more robust components and new thermal paste was applied. All ceramic caps were upgraded to multi-layer ceramics. Every standard Diode and Zener Diode were replaced with better quality and more robust low noise modern replacements. Spacers were used on several components for improved air circulation. old relay was replaced with new high quality omron replacement and was soldered with cardas audio silver solder. all 8 Rectifiers were also replaced and upgraded to fast recovery

5. Every Single Transistor in the amp section including the Output transistors have been replaced with modern onsemi high quality replacements. Several of the known problematic resistors on this section have also been replaced with much more robust carbon film resistors and placed on raised spacers for better ventilation. Emitter Resistors have also been replaced with higher quality non inductive wirewound resistors. New thermal paste and mica insulator pads have been applied to output transistors.

6. The Control board was completely recapped using Nichicon muse ultra Fine Gold audio capacitors. All transistors in this section except the Field Effect ones have been replaced with modern matched Onsemi for continued reliability.

7. The Preamp board was completely recapped using Nichicon muse ultra fine gold audio capacitors. Zener diode and known problematic resistors have also been replaced.

8. Old deteriorated board foam supports were removed and proper pcb standoffs were installed

9. Factory main 6800uf filter capacitors were replaced and upgraded with Nichicon muse gold capacitors which not only sound the best but also the upgrade results in better, tighter bass control and response.

10. Safety Capacitors in the power switch and switched outlets have been replaced with high quality Murata safety capacitors

11. Volume and balance control have been thoroughly cleaned with deoxit and then treated with deoxit gold for preservation.

12. Input Selector, Tape Selector, Gain, Tone defeat, Filter high, and Subsonic switches were all completely desoldered, removed, disassembled, cleaned to like new condition, treated with deoxit gold for preservation and resoldered using Cardas audio this task alone required several hours of work a total of 6 switches!! See example picture of one of the switches before and after. This ensures like new operation and reliability.

13. Bass, Treble, Loudness, Mode, and Speaker selector switches were completely cleaned and flushed with deoxit and treated with deoxit gold for preservation.

14. Power switch has been completely dissembled cleaned and contact assembly has been reversed to utilize unused contacts in housing this ensures a like new operation of power switch.

15. All RCA inputs, Tape, and Headphone connections were cleaned and conditioned with DeOxit D5 for prolonged life and protection.

16. Old speaker terminal plates were removed and new custom CNC machined heavy duty Nylon plates were made to original factory size. New Five way Audiophile Grade Tellurium copper binding posts were installed. The new binding posts are a serious upgrade! they provide a much stronger electrical connection between your speakers and the amplifier, additionally they allow many traditional speaker connections and also provide banana jack connections which makes it easier to connect and disconnect new speakers. They were soldered using Cardas Silver audio for maximum sound quality.

17. All corrosive glue used to secure capacitors has been removed and cleaned from boards. All corroded adjacent parts were replaced.

18. All four adjustment, trimming potentiometers have been replaced with modern Bournes multi-turn, sealed units.

19. Power test was performed with an eight-ohm dummy load and a 1khz continuous sine wave both generated and then analyzed out of the amp by a professional state of the art ultra low noise audio analyzer. both channels were checked at factory rated power (see Pictures).) THD is about .03% per channel at 60 watts quite impressive for an amplifier from the 70s!

20. Faceplate and knobs were removed and properly washed, cleaned, disinfected and hand polished. Light dust was removed from chassis with compressor and brush.

21. Top and Bottom case covers were sand blasted then powder coated in satin black. (Note due to powder coating process very slight imperfections that are present in the metal of the covers are easier to notice when the light shines on them at certain angles still displays beautiful just thought I mention it.)

22. All solder points inspected and when needed reflowed. All solder work was performed with high quality Kester solder for non-audio path and Cardas audio solder for audiopath. professional Hakko soldering equipment was used This results in good solder work, no lifted traces or damage to the boards.

23. All functions tested on bench and under load for a period of 24 hours. Then, factory adjustments were rechecked.

24. The lovely phono section was tested with a turntable for several hours.

25. Adjustments and measurements were done with a combination of calibrated Fluke, Agilent, Audio Precision, Sound Technology measurement instruments, Tektronix oscilloscopes and ultralow noise highly accurate Audio Analyzers among other professional audio repair tools. New installed Multiturn Trimmers help dial in factory adjustments much more accurately and prevent drift of settings due to vibration and are sealed to prevent corrosion. All factory service adjustments have been performed per factory service manual.

 Final Notes:

Once the Device has Passed all Rigorous Lab stress testing, it undergoes a full 7-day audition in our listening room under real world use! its connected to multiple sources and speakers of varying loads and design. Once a device performs as well as it sounds it is deemed comprehensively restored. The Kenwood 7100 is one of our reference units in shop! Kenwood was the king of amplifier design and innovation in the ‘70s and this can be clearly seen in the 7100, which has their trademark dual power supply design. This particular Kenwood 7100 is one the nicest ones we’ve had the privilege of restoring. The cleaning of all the switches was a very intricate and delicate work but the results are outstanding and a privilege to witness and hear something to this level of restoration you have a clean like new audio path thru all the switches. Upgrading of the speaker connections also represents a huge leap in sound.

How does it sound? Highly Detailed Powerful, Musical and Dynamic!

The impact of all the high quality modern replacement parts and audiograde capacitors combined with the now upgraded dual power supply is truly something remarkable!

Music Reproduction is Highly Detailed, Bass is Deep and powerful, Vocals are realistic and instrument Separation is nice and clear thanks to the reduction in dynamic crosstalk that the dual power supply achieves truly spectacular!

Kenwood created a monster with this amplifier this is a very powerful amplifier it drove even my inefficient Elac speakers with no problems. Kenwood was a pioneer with their dual power supply design amplfiers which the whole industry adopted years later It is quite remarkable!

Several months of work have gone into this restoration. Kenwood Knocked it out of the park with this amplifier it’s a beautiful piece of modern art Representing a special period in audio, it was a privilege to restore this unit for future generations to enjoy.

A pair of 8ohm speakers with an efficiency rating above 86db is highly recommended. A pair of Klipsch RP600Ms would go great with this 60 watt per channel amplifier it paired perfectly with my kef ls50.

Ill end this long description by saying this is one of the finest amplifiers Kenwood ever produced and one of the best top of the line units produced in the golden age of the 1970s. We have strived very hard to make sure from planning stage to the end of this restoration that this would be a restoration that lives up to the 7100 badge and legacy. This unit is privilege to own and will be the center piece of its new owners collection!!

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About Solid State Audio

We are a small business Located in New Orleans, Louisiana born out of a lifelong love and appreciation for vintage Hi-Fi audio. Our mission is simply to restore and preserve some of the finest audio gear ever made.

Like many of our clients, we are also passionate Audiophile and music lovers. Listening to music is an experience and nothing creates quite the atmosphere as the sounds and aesthetics of a vintage Hi-Fi audio system.

Unlike other shops, at Solid State Audio, vintage Hi-Fi audio equipment sales and restoration is all we do! We have the appreciation, experience and proper test equipment for your audio gear.

We have many years of experience performing restorations exclusively. Our restoration lab features a comprehensive collection of audio test equipment from some of the renowned names in the industry like Sound Technology, Audio Precision, Tektronix, Keysight, and Panasonic just to name a few. In addition, we have a full workshop including a CNC Machine to help us custom design new parts or printed circuit boards to perform proper repairs or upgrades to equipment.

From inception, it has been our goal to provide our clients with not only a comprehensive restoration but the absolute best customer service and communication experience during and after their restoration or purchase. Please don't hesitate to reach out with any questions about our restoration process or audio gear for sale.

Please Visit us at solidstateaudio.com for all your Vintage Hifi Needs!

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Terms and Conditions PLEASE READ IMPORTANT:

As with any electronic device or appliance, both vintage and new, there is always a chance that something will fail. Even though new parts are used and all adjustments and care have been taken in the repair or restoration, this possibility exists. For that reason, any vintage or new device sold by us; is sold in AS IS condition and all sales are Final. Our feedback speaks for itself and the amp will be packed professionally and shipped via FedEx, with signature required.

Thank you for visiting Our listing! All sales are final! please read entire listing to see what’s included. test equipment is used for reference and demonstration purposes and is not included in listing. Please ask any and all questions before purchasing an item. Items will include free shipping only within continental U.S. I’m sorry, but at this time we do not offer international shipping.