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The Upgrade Company

+1 269-352-7609

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 (6) of David J. Schulte's patents




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The Upgrade Company, AudioVisual Equipment  Dealers, Harbor Springs, MI 











Contact Info

The Upgrade Company

+1 269-352-7609

This email address is being protected from spambots. You need JavaScript enabled to view it.

 (5) of David J. Schulte's patents

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+ 30 Day In Home 100% Refund Period

+ 5 Year Parts & Labor Warranty with Every Signature Edition Upgrade

+ 100% GUARANTEED to beat ANYTHING else on the market!


Nothing we sell ever comes back.  

We don't even have to advertise.  Once our clients experience for themselves the extreme high performance & "bang for the buck" we deliver, they keep coming back as funds permit.  

The Upgrade Company would not continue to be A+ rated on the nationwide BBB algorithm month after month unless we were delivering on our promises.

Please call +1 269-352-7609 to place order

EAR Testimonials

Unsolicited Customer Testimonials - Every client has paid The Upgrade Company LLC in full.   No kickbacks, no commissions, no fees of any kind for recommending our products and services.

Ultimate Level of Music

I am extending my sincerest thank you today to everyone at The Upgrade Company for helping me to achieve the high level of music & video performance I've longed to achieve for well over two decades.  I could never have achieved this ultimate high level of music as well as video reproduction without The Upgrade Company's help and unique knowledge.  This afternoon, I've been listening to my music collection and I cannot believe the incredible inner detail and sheer holographic realism present in recordings, even older standard 16bit/44khz CD's, all thanks to you.  Concert videos & movies look fabulous, nothing like they do in even in the best showrooms.  

Your Audio Research, EAR, Bel Canto, Oppo, McIntosh hardware upgrades have brought out the best in music and video reproduction I've experienced.  The TimePortal "RFI EMI Ridded" power cords, XLR interconnects& speaker cables are sonic stunners and really completed each system.  

I cannot thank you enough!  Thank you, thank you, thank you...

Extremely Satisfied Customer,

Paul Elliott
New Prague, MN.

Esoteric Audio Research 834P Phono Preamplifier "Signature Edition upgrade"

I wanted to let you know how happy I am with the Signature Edition Upgraded EAR834P phono preamp.

As you know, I had an Audio Research PH5 Phono preamp. Happy with the sound and quality of Audio Research equipment, I wanted to spend $12,000 on an Audio Research Reference 2 Phono Preamp to bring a reference sound to my large vinyl collection. After our discussion, you talked me into demoing & comparing your Signature Edition Upgraded EAR834P for a fraction of the price of a ARC Reference Phono 2.

I am glad you did…WHAT A PHONO STAGE. The Signature Edition EAR834P has transformed my vinyl collection. It has never sounded better. Way beyond my Audio Research PH5 and better than the stock REF 2. I have been melting away in my listening chair ever since. The liquidity, velvety, buttery shimmering luscious musicality is WAY over the top and crystal clear and dynamic and powerful all at the same time. Huge holographic stage. How do you pull all this off?

The TimePortal Silver Reference RCA interconnects I bought from you were inserted between the EAR834P w/SE and my Signature Edition upgraded Audio Research Reference 3 preamp you guys upgraded so well. I've tried lots of other cables and found that I like TimePortal Cables the very best once again. Great deal. Saving me thousands.

I am really glad we found each other. As an audiophile for over 3 decades, I was positive I had seen and heard it all. Now I find I still have much to learn. The Upgrade Company Signature Edition upgrade focus on ridding radio frequency contamination really and truly is "the missing link" to achieving perfect signal integrity and sonic excellence.

Thanks a million and keep up the great work!

Paul Elliott

EAR P 834P Phono Preamp Upgrade

My EAR P 834P phono preamp from Tim de Paravicini of EAR cost me about $800 new in the early 2000's. I've been using it ever since.  My VPI Scout turntable has undergone many transformations over the years:  five layers of isolation underneath the chassis, upgrade JMW-9 to the Signature tonearm, TT weights, all VPI upgrades, 2 Origin Live DC motors and controllers driving a heavy steel Aerex flywheel, and a platter upgrade. One of the things that makes this hobby fun is talking to other audiophiles and learning from each other. A real nice guy recommended tubes that really improve the EAR 834P's performance before I had it upgraded: NOS 5751's or 12AT7's instead of the stock 12AX7's. Good tubes make a huge improvement in most circuits. But nowhere near fully shielding the unit inside from RFI/EMI and replacing parts with the very best available.

My Van den Hul Colibri cartridge demanded more from my phono preamp to really show what it could do. One audiophile mentor shared with me that the EAR 834P with good NOS tubes will respond very well to capacitor & other upgrades.  Working with David several times previously, I knew he was the guy for the job. David has a great ear and knows there's a lot of bullshit out there with high prices to match.  He will not perform a mod that will not live up to his reputation. He'll just say no.  I have learned to trust him greatly.

With The Upgrade Company's trade secret & proprietary shielding and part upgrades including V-Cap's, he felt they could voice this preamp just right, so Upgrade Co. undertook the job.

Shortly after sending it in, I had a good feeling when David said it had just starting burn in for a couple hours yet it was already sounding better then 2 really big name stock phono preamps they keep on hand for comparisons.  I could hear the excitement in his voice.  This preamplifier has its detractors aplenty, but EAR owner/designer Tim de Paravicini has done a lot of work for several big record labels including Mobile Fidelity and Island, as well as supplied his tube equipment for many recordings.  The EAR 834P has a few hard core fans.  I'm now one of them.  This preamp sounds supremely detailed and musical now.

The stock EAR 834P exhibits a warm tube coloration, as is often said.  However upgraded it now sounds super accurate and fast but amazingly still warm! It now sounds extremely open with great musicality, pace, rhythm, great articulate bass, and a sweet high end.  Acoustic bass sounds so realistic now. I can't stop playing my vinyl since I got this back. Jimi Hendrix's box set West Coast Seattle Boy and Valley's of Neptune-both released in 2010 put Jimi right in your living room with the genius himself.  Since Upgrade Company upgraded the EAR 834P, it is truly a "state of the art" phono preamp.  I haven't found anything that can approach it's performance now.  I'd gladly put it in direct comparison with anything at any price if anyone wants to come by to compare.

Every upgrade I've had from The Upgrade Company has exceeded my expectations.  For those of you with any upgrades done mid-2010 or older, you really need to get yours updated.  I had my NuForce Oppo 83SE universal player updated and it was truly night and day over their original upgrade from mid-late 2010. I've got the balanced output version. Even the digital outs now sound superior to the original upgrade, and now Blu ray and DVD movies look even sharper and more saturated over HDMI.                                          

Bret L. Miller
Springfield, Illinois

Page information last updated: 20/04/2017

Disclaimer: We believe but do not guarantee that the information on this website is correct at the time of publication.

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