Esoteric Audio Research859usedEAR (Esoteric Audio Research) 859 Triode Tube Amplifier**Please click here to check out our newly launched SkyFi Audio website with additional items for sale**This is a full tube, enhanced triad mode amplifier. By full tube we mean tube preamp and tube...2499.00

EAR (Esoteric Audio Research) 859 Triode Tube Amplifier [Expired]

no longer for sale

**Please click here to check out our newly launched SkyFi Audio website with additional items for sale**

This is a full tube, enhanced triad mode amplifier. By full tube we mean tube preamp and tube amplifier sections. It uses the standard EL519 tube producing about 13 watts.

It's quite a neat design and advancement over your standard triad or single-ended amplifiers. I suspect this would be a pretty neat way to drive high-efficiency vintage speakers such as Tannoy, Altec's, or Klipsch. With 13 watts this should be plenty of power for any of those era, or other full range high-efficiency speaker.

It's beautiful in aesthetics with a chrome front faceplate with gold knobs.  The two tube cages are kind of neat sitting proud in the front of the amplifier.  Next you'll see the main power transformer sitting between the two tubes, and then towards the back you'll see the output transformers wired in short runs to the speaker outputs.  It only features 8 ohm taps, but that should be the most standard tap it's going to encounter.

It's a very simple design internally. I've had a look and there's a couple of small driver tubes and very few parts.  I like to see as few parts as possible like in this simple tube designed amplifier, to not get in the way of the signal path or any other interference.  It is elegant in design and simplicity and has received great reviews from all over in Europe and Japan over the last 20 years.  There are later versions but this is probably the original version.

It says on the amp that it's utilizing Yoshino output transformers, not sure what those are exactly, but they sound pretty neat. Functionally it's a very simple integrated amplifier with 6 inputs and no outputs other than the tape output.

On the front there is a power switch, input selector, and volume control - nothing else. And no remote control.

It came through our lab and produced its full 13 watts with very little harmonic distortion, and without any drama whatsoever.  

Cosmetic condition is top notch and it cleaned up nicely.  I don't see any scratches, dents, or anything else to speak of. The chrome-work is still pretty intact, the two tube cages are fully painted with no issues whatsoever, and the front panel looks absolutely stunning.


This item will be professionally packaged and insured for safe transit to your home. 

Please click here for detailed specifics regarding our specialized packing process that separates us from the rest.

If we don’t have the original manufacture's packaging, we use heavy duty double ply corrugated boxes with Instapak expanding foam custom inserts.  In many cases this has proven to be better than the original packaging.  We also use high quality fiber reinforced tape to seal our packages.  Lightweight items will be bubble wrapped and shipped in a high-quality box. 

This item is available for pickup in Ridgewood, NJ or Union Square, NYC (with convenient parking in the building).

NJ Residents or anyone picking up without a resale certificate will need to pay NJ Sales Tax.

Use the Buy It Now button and we will cover the PayPal fees.

Thanks for looking and be sure to call or text 646.852.2073 with any questions. 

Please also click here to visit our Audiogon store to see the rest of the items we have for sale.



SkyFi Audio is a small startup business specializing in the purchase, reconditioning, and reselling of select high-end audio equipment.  We only buy equipment the we admire and are passionate about. No mid-fi, no gimmicks, no junk. 

Each piece of equipment is cosmetically restored and fully tested in our well-equipped lab by an engineer with 30+ years of experience in the HiFi world. If it does not meet or exceed the original manufactures specifications, it will not be sold.  We are very selective about the equipment we purchase, focusing on mostly analog, high-build quality, American, and European built units.

Through our sister company, which is an authorized dealer for McIntosh, Audio Research, Sonus Faber, ClearAudio, Pro-Ject Audio Systems, and Sony ES, we have access to OEM parts, service, and support.  If you are local and looking for new equipment from the above-mentioned manufacturers, please drop us a line as we can arrange both sales and professional installation in the tri-state area.


We do not accept or review any offers that do not go through the official Audiogon system. We have too many items for sale and it’s nearly impossible to keep track of offers outside of the official system. Please don’t message, email, or text any offers. 

If you do not see a “Make an Offer” button, it means we are not considering any offers on that item.   


We prefer working through PayPal which allows you to use a credit card or bank transfer. We do not charge extra for any payment fees if you purchase the item at the asking price.  You can also send us a personal check (which will need to clear before shipping), certified check, money order, or wire transfer. International clients without access to PayPal should use a bank wire transfer. 

If you are picking up an item we do not accept PayPal.  You must pay in person with cash, certified or bank check, or wire transfer.  If you make a PayPal payment and are picking up the item, it will be returned. 


We accept trade-ins of equal or lesser value under certain conditions.  Simply ask and let us know the exact model, condition, and the accessories that are included (such as the original box, remote, cables, manual, etc.).  We will only consider high-end equipment from mainstream manufacturers such as McIntosh, Mark Levinson, Audio Research, Krell, etc. and will typically pass on displays, projectors, receivers, dated surround processors, and mid-fi equipment of any type.  We will offer a fair value for your equipment, but keep in mind we are running a business and will need to be able to resell the equipment at a profit after investing a great deal of time and resources in testing, certifying, repairing, cleaning, and packaging the incoming equipment.  If you are looking for top dollar we suggest attempting to sell it directly to an end user on your own.

SELL US YOUR GEAR (Working or Broken)

We will also purchase your used or broken gear and arrange pickup if you are in our local market. Just drop us a note for a quote but be sure to include the condition and what is included. 

HOW TO VISIT US                                                                                                        

We are currently operating from a residence in Ridgewood, NJ.  You are welcome to make an appointment if there is a piece of equipment you would like to see in operation before or after purchase.  We have a well-equipped, dedicated listening room with tons of equipment of all makes and models.  We are not a store, so please don’t make an appointment if you are just curious as to how a speaker or piece of equipment sounds.  In essence, no tire kickers please.

If you are in NYC and cannot make it out to Ridgewood, we can arrange pickup in Union Square (14th Street) after the purchase.   You can call or text 646.852.2073 with any questions or to schedule an appointment.  We can also arrange to install, calibrate, and tune the gear in your listening room if you are local to the area.  This is super useful when purchasing large speakers or heavy amplifiers.  It is also great for ensuring your new turntable is setup correctly in its final resting place.  

Thanks for looking and please click here if you would like to receive a list of the equipment we receive from time to time.  We promise not to bombard you with junk email.


skyfi member since January 2012  Verified Dealer
Last 12 months
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