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The Upgrade Company

Customer support and communication is an issue taken very seriously by The Upgrade Company. We strive to exceed your expectations. 
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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

Customer support and communication is an issue taken very seriously by The Upgrade Company. We strive to exceed your expectations. 
Please drop us an email or voicemail today.  We promise to reply to your inquiry as fast as possible.
Contact Information
Office Hours: Monday-Friday 10am-6pm, PST


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

+1 702 708-4378

 (5) of David J. Schulte's patents




The 8th Annual Positive Feedback Online's Writers' Choice Awards for 2011 - The Best of the Best!
Upgrade Company's Signature Edition Marantz Modifications


I realize that my writer's choice award for 2010 was for products that I hadn't officially reviewed till the January/February 2011 issue. Give me a break. I am slow to turn in my handy work. And besides being that the Dave's are both teachers, I would never use the standard issue excuses of blaming the dog for eating my homework or I left it in my friend's locker. That would be worse than just being late. But seriously, I strongly feel that one of the best things I have done in regards to an audio purchase in as many years that I have been in this beautiful hobby of ours is to send my gear to The Upgrade Company to have Mr. David Schulte perform his Signature Edition modifications to my gear. Or I should say, work his magic on it. With the permission of our esteemed editors, I would like to vote The Upgrade Company for a second year in a row as one of my top choices for the Writers Choice Award. The reason is, for the upgrade they performed earlier this year to the original modifications. When Mr. Schulte emailed me earlier this year to let me know he had some further improvements to make on my gear I was skeptical. I didn't think there could be improvements on the improvements they already made to my stock Marantz amp and CDP. But believe me they did the seemingly impossible and improved an already great modification further. Way further in my opinion. Please stay tuned. I am working on getting the details in as soon as possible.

Read the review here

Francisco Duran



positivefeedback1 positivefeedback2


The Upgrade Company - Taking my Marantz PM15S1 Integrated Amplifier and SA15S2 SACD to a Whole Another Level
by Francisco Duran

As far back as I go in this great hobby of ours, I can remember reading reviews of products that were just short of reference quality in one or all areas of performance. Comments like "bass performance approaching but not quite up to the very best" or "the treble is just shy of the top echelon" were bestowed upon less than stellar gear. I've often wondered, what makes that product just shy of the very best? Is it the circuit design, parts upgrade, or both? Or to put it another way, what would one have to do to make that product compete with the very best?

Fast forward a few years to a fledgling Greater South Bay Audiophile Society, getting to know many audio manufacturers in those early years, and listening to many of their audio products. Dave and Carol Clark and a few more of us turning a lowly GSBAS newsletter into a full-fledged magazine, audioMusings, and the gear kept coming. Later audioMusings partnering with David Robinson, Positive Feedback Online was formed to bring a Forum for the Audio Arts to the Internet. To say that I have listened to my share of top quality hi-fi gear would be an understatement, through these ventures and audio shows and friends' systems. I have also had systems made up of some fine gear through the years.

But the itch to improve things didn't stop with just swapping gear out in my system. Early on I felt that a very good way to improve one's gear, without selling it and replacing it with something more expensive, was to have it modified. Down through the years I have had modifications done to select pieces of gear in my system, some of them done by very competent people in this industry. Each time the modifications improved the sound, but not always to the degree that was expected. One good argument I ran across in favor of modifying one's gear one night on the Internet was titled, "Go Forth and Modify" by Brad Mitchell in the Internet magazine Affordable Audio. It was in their issue 35 from November 2008. In it Mr. Mitchell gives a rational explanation of how your audio dollars are divided up by manufacturers. He also mentions the fact that "There are many high priced products out there that use mediocre internal parts." This was not only shocking to learn but a bit of a let down. One would think that when you spend your hard earned cash on very expensive gear, you are actually getting the very best.

Fast forward again a few years later and I found myself in a similar situation. It was time again to upgrade my system, but based on past experience, the urge to upgrade my gear through modifications was strong. Enter David Schulte, owner of The Upgrade Company of Harbor Springs Michigan. The Upgrade Company is one of those companies whose name pops up when you are doing an Internet search late at night for the best company to modify your gear. In fact, I can't remember how I initially came across them. I can tell you that from the very first time I contacted them, January 25, 2008; it took me almost three years to make up my mind and have my gear "upgraded" by them. But I am getting ahead of myself. The reasons for my procrastination were many, and typical of the incredulous audiophile. This doubt was partially brought on by the claims made on The Upgrade Company's website. In it they state that the modifications they do actually bring gear to state-of-the-art status. They also mention the fact that there are many cheap parts in expensive high end gear that are also found in cheap and cheerful entry level gear. I have read that last statement before. Okay, but would the bass be improved? Would the treble sound better? Will it sound more musical? Will it be worth my money? These and many other questions swirled in my mind as I did my research.

The Upgrade Company goes a long way in easing your concerns when you shop through their website. Several comments caught my attention firmly concerning their policy. They have over 28 years experience in upgrading and modifying high end stereo and video equipment. Customers are offered a 14 day in home trial of their work. There is a 100 % buy back guarantee, five year parts and labor warranty on customer owned gear that they modify. The clincher for me, and one that answered one of my many questions, was that once your gear is upgraded, it will compete with (stock) "cost is no object" models. And as if that is not all, some of the comments directed to David Schulte would make any audio dealer green with envy; "Dave makes a total commitment to you when you are one of his customers," "his service is second to none," "Dave is a true gentleman," "as stand-up guy as I've come across," and "may god bless you always!" Oh yes and he answers his phone calls and emails promptly, my quote. When was the last time you said anything like that to your audio dealer? And still I hesitated. After all, how could anybody take my treasured stock from the factory audiophile gear and make it better. Please read the website for more details on their policy. Okay, stay with me guys, just one more thing. Just a few of the many customer comments about their work; "the entire presentation of my digital playback is state of the art," "best move I ever made," "worked his magic on …," "outstanding work," are just a few of the many positive comments about their work. It was sounding better and better in favor of a mod.

First here is a little history about the gear that I finally sent to have modified. The Marantz PM15S1 integrated amplifier and SA15S2 SACD player were purchased late in 2009. Partially due to a synergy with my speakers, and the features appealed to me. After many years living with a couple of bare bones passive line stages, the list of creature comforts on the PM15S1 was inviting. The Marantz gear is definitely in the smooth sounding camp as opposed to the razor sharp and clinically neutral. Coming from the Marantz Reference Series, that pedigree is undeniable with their solid build and handsome looks. I was told by very reliable sources that the smallest amp and SACD player in the Marantz Reference Series line sounded every bit as good as their bigger brothers, except for sheer power in the amp and a few missing creature comforts from the CD player. Seems it had something to do with a smaller parts count. Besides they are less expensive and my speakers really don't need massive amounts of power to get them to open up. The 80 WPC of the PM15S1 fit the bill. This forty pound integrated amplifier came equipped with an MM/MC phono section, headphone amp, record out facility, speaker switch, (for headphone listening), tone controls and WBT speaker binding posts among other niceties. The CD player can be used as a stand alone DAC or transport. The amplifier is about as far away from my previous hair shirt audiophile approved system as you can get yet far short of an all in one massive HT amplifier. I love it!

I wrote in my review of the stock SA15S2 that it has "a smooth yet detailed demeanor," "natural sounding midrange," and "realistic tonality." But as nice and smooth as it is, it often times leaves one wanting for more musical excitement. Although very nice sounding, this combo was lacking transparency, dynamics, some inner detail, and a bit of that sonic excitement. I also said in the review that "SACD's sounded way more natural…making regular CD's sound more hi-fi and electronic in comparison." But they were smooth! What I didn't know at the time was the dramatic change to the Sonics the modifications would bring. In fact early on, I almost sold the amp. It seems it just wasn't as good a match for my Tonian Labs speakers as I thought. Turns out I didn't have enough break in time on the amp. I have a habit of switching out amplifiers in my system quite often, and I didn't realize I didn't even have fifty hours on the amp. After over 200 hours it finally broke in and opened up… to a degree. Or so I thought.

Finally after a year of debating, researching, and thinking about it, I sent in my Marantz SACD player to The Upgrade Company for an upgrade. Sending your gear to them is painless. Owner David Schulte is very communicative with his customers, his turnaround time is fast, and the prices are very right. Their work is exemplary. During the break in and since, I have literally run the juice out of both units and they work perfectly. The amp gets a lot more time in than the SACD player. My amp is on and running at least six hours a day on weekdays and at least twelve to fourteen hours a day on weekends. And it runs cool as a cucumber, which is another reason I bought it. But I am jumping ahead of myself. After getting the SACD player back and breaking it in and loving how it sounded, something wasn't quite right. I felt I still wasn't getting the full mettle of the new modification. Feeling that the rest of my system was at fault, off went the PM15S1 amplifier to Harbor Springs, Michigan. One concern I had was that the amplifier wasn't the latest model of PM15. I have the PM15S1, and as soon as I bought it, Marantz came out with a new model, the PM15S2. David Schulte assured me that the difference between the stock units wouldn't be a problem after his modifications. In between this though, David emailed me to say that he has improvements that he didn't implement in the SA15S2 mod the first time and if I could send the CD player back he would upgrade it for the cost of shipping. Getting the CD player back there was definitely an improvement in background silence and cleanness I thought couldn't be improved. Now back to the amp, when it came back and I had some hours on it, I felt my system was a lot more complete sonically with both units modified. Now for a bit of a painful confession: Since the amp has been back, I have rarely listened to my Margules tube amp. Now don't get me wrong, the Margules is a very fine tube amp. But the mod to my integrated really closed the solid state/tube gap sonically in my system. Another gap that closed to quite a degree is the SACD/ CD performance. There is not as big a difference as before the modifications in sound between the two formats. Go figure.

The first aspect of the sound quality of these units post mod that should be mentioned is their lack of noise artifacts. That is, lack of grain, glare, hardness, brightness, smearing, or veiling. After break in it was the absence of these sonic negatives that first got my attention. The absence of these artifacts alone should be well worth the admission price to anyone who lusts after good, clean, musical reproduction. Listen to just about any sanely priced audio products, and one will find one or another of these artifacts in the sound. In fact you would have to spend up to the four to five figure price-tag to get as clean sounding as these components. I would emphasize here that in this instance, clean absolutely does not equate to a bright, thin, or clinical sound. Full, solid, clean, and musical make better descriptors. This is one amp and CD player that can really track what a recording sounds like. Similarly they are very revealing of component changes in one's system without the sound becoming merciless. Can a component sound both accurate and musical at the same time? Yes, very expensive components (sometimes) and a modified unit from The Upgrade Company. Of course, matching these components at this level requires skill and patience. When doesn't it? I got very good results with my resident JPS, Soundstring, and Music Wave speaker cables and interconnects. But I got excellent results when using two Kubala-Sosna Emotion power cords and one pair of Elation interconnects. This excellent wire transformed my system to a degree I didn't think possible. With the KS wire the system exhibited a greater degree of inner detail and extension at the extremes, yet stayed grounded in musicality. The music just seemed right and snapped into place. Of course the wrong wire or mismatched ancillary in a high end system will wreak havoc on the musical reproduction. The Marantz combo has the benefit of being matched at the factory then improved upon by the modifications. But just popping them out of the box and pressing play doesn't guarantee success. The fact that top notch cabling brought out the best in my components is telling of the quality of the modifications and proof that working and tweaking them will return worthwhile rewards.

Of course this lack of artifice brought out the best in the music. My Tonian Labs TL-D1 speakers are very accurate transducers. That area of sound that we are most sensitive to, the midrange, sounds very accurate and naturally realistic. The vocals are solidly placed, and the images are holographic and stable when warranted by the recording. A favorite composition by the guitarist Pat Metheney is "The Longest Summer" on his Secret Story CD. To quote another PF writer, Bob Levi, the piano on this cut sounded "mellifluous." The piano sound jelled out into the room with ease. What deep bass my speakers can reproduce, down to their 42Hz limit, sounded very well controlled, taut, agile, and very natural with this song. This brought out musical texture and tonality, not only in acoustic instruments, but those qualities can be heard in electric instruments as well. Does the electric bass guitar have texture to its sound? I felt so in many recordings.


One night while doing a comparison of Pink Floyd's Dark Side of the Moon LP, (Gramophone Company Limited LP), and SACD (Capitol), some interesting things were noted. In track No. 4, "Bells," the accuracy of timbre of the bells and the depth of the soundstage and location of individual bells was very good on the SACD version. When we played the LP, we felt my phono set up reproduced timbres that were more realistic and relaxed sounding. Although the SACD pulled off realistic depth of stage, it just couldn't escape CD's old inherent trick of flat individual images. This was more noticeable on the piano and vocals. It was absent with my phono rig even with my cheap and cheerful Blue Point No. 2 cartridge. The phono stage reproduced a stage and images that had better natural sounding depth and space. Now don't get me wrong, CD reproduction from this player is first rate. But it seems no matter what you do, you can't escape digitals "perfect" sound. When I sent my amp in to The Upgrade Company, I asked David Schulte to go all out on the phono section. He must have taken my advice because this built in phono section in a $2000 integrated amplifier punches way above its weight class. I have been living with it quite happily.

I mentioned this amp has tone controls in my Positive Feedback Writer's Choice Awards comments. Audio purists need not fret, they can be bypassed. Before the mod, engaging the tone controls caused a slight distortion to be heard. This noise defeated the purpose in using them, and made me want to turn them to direct mode. After the mod, this distortion was simply not there. I like the inclusion of this feature on this amp. Used sparingly they come in handy on more than a few recordings. The mod really changed their performance, using the tone controls gives no sonic penalty. To me it sounds more like a cable change when using them than a circuit that is mucking things up. And lets not forget the improvement to the built in headphone amp. The modification to my amp was a complete one, and these features for me are justification of the convenience of my integrated amp.
The treble performance blends seamlessly with the rest of the frequency spectrum. It is extended and revealing, yet naturally realistic. Swapping out my Tonian TLD-1 speakers for a pair of new NSM MS-100's that are in for review brought out a stark difference in each of these speakers top end sound. The differences between these two speakers are most noticeable in the treble region. The silky smooth performance of my modified Marantz combo again easily showed the poor quality of some Pretenders' CDs as compared to Milton Nascimento's Nascimento CD or the Ana Caram Collection on Chesky Records with either of these speakers. The strength of these modifications is to reproduce highly revealing sound yet be very musical. I have to say that listening to the Pretenders' CDs was more enjoyable than just about any stock CD player that I have heard them through.
If you want a lesson of what high quality bass, midrange and treble can sound like, just listen to the CD Blues Groove by the Jimmy McGriff and Hank Crawford Quartet on Telarc. The wide open dynamics, the growl of McGriff's Hammond B-3, the fine texture of Crawford's alto sax, and all blend together, spread out wide before me. This modified Marantz combo easily displayed this high quality recording with ease. I could go on and on with musical examples.

It is sometimes easy to slightly loose sight of reality when one is enthusiastic about a product or service they feel strongly about. I have made a similar statement last year when I reviewed this very SACD player, only it was stock. The stock Marantz components are very good audio products, but the modifications to my gear were highly successful. The modifications transformed two slightly sweet, warm, and competent sounding products to ones that will compete with others costing many times their retail price. But are they the best out there? Are my amplifier and SACD player "state-of-the-art" status? Let's just say that David Schulte and company have pushed these units to their sonic limits in regards to their inherent design. And let it be said here that these upgrades are very thorough. Over 150 parts were changed in my CD player alone, plus high quality shielding and damping were also used. The Upgrade Company has many years of experience modifying the great high end stereo and video products of the world. Many fantastic statements from their customers are made on that website. But these claims are from extremely satisfied customers with many years experience in this hobby who have trusted The Upgrade Company with their mostly expensive high end gear. The proof is in the listening. Count me in with their many satisfied customers. To say that I am pleased with my decision to finally send my gear in is definitely an understatement. I am very satisfied with the outcome. If you are tired of riding that expensive audio merry-go-round or you have a treasured component you would like to have improved far beyond what you think could ever be, have a serious look at this company. What have you got to lose?

The Upgrade Company
David J Schulte
1222 Walkabout Lane
Harbor Springs, MI 49740

Page information last updated: 06/05/2020

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