Professional
Preamplifier Upgrades

Like classic FM Tuners, classic preamplifiers, especially classic tube preamplifiers, can also benefit substantially from a professional upgrade by Component Plus, USA.

If you have an older preamplifier designed by one of the great designers like Manley, Hafler or Marantz, and you are thinking of upgrading to something finer and more expensive, perhaps you should reconsider. Little new in the way of circuit design has occurred since these classic designs were first introduced.  What is new and improved is the quality of the components and material now used. Given that reality, instead of spending a lot of money stepping up, consider getting a professionally engineered Tube Preamplifier Upgrade from Component Plus, USA instead.

Who is Component Plus? (click here)

Words of Praise for Component Plus Upgrades
Here are a few testimonials from Audiogon members, who as members are more discriminating than usual. Their remarks, with the exception of those of Joebone, were unsolicited words of praise, but after receiving them, we did request permission to print them here using their Audiogon name.

Joebone wrote: "His mods to my Accuphase T-109 tuner unquestionably reflect genuine value.    The tuner is even quieter than it had been before, leading to a degree of resolution, micro-dynamics and transparency that exceed one's expectations from FM broadcasts.    Bass information is much more precise . . . and on good classical and jazz programming, brass instruments are showing genuine sheen and bite.   The lateral soundstage is also improved, and I think there may be a bit more depth.   On the right material, I find a transparency reminiscent of master-tape-in-a-control-room experiences and monitor-board recordings from my prior life as a professional musician. . . . I would not hesitate to again utilize Joseph [Chow]'s expertise."  (Joebone)

Hrtless, who had his Kyocera tuner upgraded wrote: "First let me say, you do beautiful work. The insertion of the RCS connectors and the IEC plug is very well done. Second, I will be very proud to show off that silver sticker on the rear of the unit that notes that you modified the tuner." (htless)

Cola 45 wrote: "I got the tuner today [a TU 9900]. [I have]just one word for you. You are amazing. Thanks. (cola 45)

Gargoyle, who purchased an upgraded Sansui TU-719, wrote: "I got the tuner on Friday and got it powered up today. All I can say is WOW! I never knew FM could sound this good. This Sansui is fantastic and it looks like it just came off the shelf not like a 20+ year old unit. You are a true credit to the hobby." (gargoyle)

Nealhood, who was a little uncertain about buying an upgraded Sony ST s555ES, wrote after receiving it: "The bass and midrange on this Sony sound quite natural and pleasant. Overall I am very pleased." (nealhood)

Boozerocket, who purchased a Sansui TU-9900 for what he considered a good price, wrote: "I received the Sansui yesterday. This is the tuner I have been looking for. It is truly exceptional." (boozerocket)

Finally, Stressnot had these lengthy comments to make about a Yamaha T-85 that underwent extensive upgrading modifications: "Overall, the tuner sounds incredibly good. Maybe it's taken a little while for some of the new parts to properly burn in, but as I listen to it now, I am hearing sharp detail, without it sounding at all harsh. The bass goes deep, but remains focused, and the highs sound smooth, but not rolled off.

"I think that the IEC AC inlet installation alone is a great improvement. It allows me to use a much better power cord, which provides an airy and expansive sound. But of course, all the other new parts make it all even better.

"I just had an FM outdoor antenna installed, and get a clear, beautiful sounding signal on many distant as well as local stations with it connected to this tuner." ( Stressnot)

We want our customers to be pleased and so far they have been.

Why Upgrade?
We are all aware that even in classic designs of old by McIntosh, Marantz, Hafler and Manley, the component parts were not commensurate with the genius of the design, that replacing an OP amp, IC, critical capacitor or diode with a superior one (unavailable at the time) that takes advantage of recent improvement in component materials and design will make an immense difference in the sonic performance.  But few of us realize that all the materials, even supposedly minor ones like the wire and hardware, and the entire architecture of the unit design contribute to its performance, not just obviously critical audio components.

Let me cite an example.  Joseph was recently asked by a friend to examine his VTL Stereo 90 tube amplifier.  Since it was an old design, there was a veritable snake pit of wires coiled throughout the amp.  Joseph told his friend that there were a few caps that should be upgraded with better quality ones, but that the main task was to replace the poor, low grade, noisy wire snaking through the unit.  His friend seemed disappointed that he was not going to engage in a wholesale upgrading of components.  But in fact, replacing inexpensive, thin 24 AWG stranded copper wire with larger, low noise, high Q 18 AWG wire and rerouting it if necessary, is critical to the performance of any unit.  Of what use is it to have a marvelous circuit and superior components in it if the wire that will carry the signal is simply not up to the task? When upgrading any electronic gear, Joseph believes we must examine the unit as a holistic design from the AC plug through the output jacks and speaker plugs.  Joseph told his friend that he would replace the AC cord with a superior low noise, high Q power cord; that he would replace all the low grade critical wires running throughout the unit with high Q, low noise wire and reroute them if necessary, that he would replace the old RCAs with high Q gold plated Teflon RCAs and that finally, he would replace the old speaker posts with new, high Q gold plated ones.  Only then would he consider replacing key components in the circuit.

The before and after modifications measurements and improved performance were immense and visible on shots of the waveform.  Three hundred dollars in upgrades had utterly transformed the amplifier. 

Which brings us to a key point: We have almost all of us been made terribly sensitive to the quality of our interconnects, and more recently to the quality of our power cord, though still not enough of us pay as much attention as Joseph to matching the Q and capacitance of our interconnects with our units.  Despite that, we still do not appreciate  how critical the layout and quality of the internal wiring in our units is.  People boast of the Burr Browns and Blackgates in their units, but then utterly ignore the mass of thin, inexpensive stranded copper wire snaking through the unit from the power cord (which is really nothing more than 18 awg lamp cord) to the outputs, or the fact that the 18 AWG  ungrounded power cord is totally inadequate to the task and results in a considerable loss of micro detail and leakage due to poor dielectric.

If large sonic improvements are to be made and they can be made to expensive Manley designs as well as to a modestly priced preamplifiers purchased on eBay for under $500, we have to look as deeply as possible not only into the circuit path and the quality of key components used in it, but also into the sound characteristics of the materials used at the smallest level possible, such as the wire.  This search for distortion and noise at the minutest circuit and material level begins 1) out of respect for Q [defined as the “quality factor of an inductor or capacitor.  It is the ratio of a component’s reactance ... to its effective series resistance.” Dictionary of Electronics] and 2) out of respect for the elimination of noise.  

Every upgrade must first attack noise wherever it occurs, even in the AC line, with the goal of lowering it because lower noise levels expose the sonic characteristics of individual components.   No designer, no matter how fine his ear, can improve a design below the noise level, for at that level he cannot hear the difference between one component value and another, one circuit modification and another.  Low noise permits the designer to hear more clearly the very fine sonic differences small component changes and slight circuit modifications make.  And what is true for the designer is also true for the listener listening to music.

In response to various people asking first that Joseph upgrade their tuner, then that he upgrade their amp and/or CD Player, Joseph has decided to accept a limited number of quality preamplifiers for upgrading.  If he doesn’t feel your preamplifier merits upgrading, he will tell you, and e-mail you a list of prospective preamplifiers that might satisfy your budget and merit upgrading. 


Often the performance from an upgraded classic older preamplifier will exceed the performance of a much more expensive tube preamplifier.  For example, an VTL 2.5 with $550 in upgrades (for a total investment, including market value of the stock VTL 2.5 of $1275), including line balancing output transformers and balanced output jacks, thoroughly trounced a stock VTL 5.5 in virtually every sonic parameter, including balanced outputs, despite the fact that a stock line stage VTL 5.5 goes for about $1750 on Audiogon. And an upgraded VTL Stereo 90 amplifier thoroughly trounced a pair of stock 200 watt VTL monoblocks in every area but bass energy and impact.

Upgrade Packages

The prices below indicate a range of prices. To get an exact quotation for your preamplifier, write to Joseph Chow at audiohorizons@yahoo.com or call Audio Horizons to discuss your units with him.

Component Plus, USA offers two upgrade packages:

Audio Upgrade. Cost: $375-$500 depending on the make and model, including parts.  Upgrade includes the following:

  1. Replace the RCA outputs and three RCA inputs with new high Q, gold plated Teflon RCA’s.
  2. Upgrade the internal wiring from the 22-24 AWG stranded copper wire between the RCA’s and the PC Board with 18 AWG low noise, high Q wire.
  3. Upgrade the internal wiring from the AC plug pins to the power supply and from the power supply to the preamplifier.
  4. Add an AC line filter between the AC cord or IEC and the transformer.
  5. Upgrade all 8 to 10 audio stage coupling capacitors with Reliable Multicaps.
  6. Upgrade the audio stage Op Am IC’s with Burr Brown or similar quality, using a plug in socket so when improved Op Amp IC’s later become available they can easily be inserted.
  7. Upgrade the power supply capacitors with Blackgate capacitors.
  8. Upgrade the rectifier diodes with Fast Start Soft Recovery diodes (FRED’s).
  9. Clean the interior and exterior of the preamplifier.
  10. Test all the tubes if it is a tube preamplifier.
  11. Provide an itemized list of parts replaced, including the replaced parts.

Premium Upgrade.  Cost: $500-$1000 in most solid state preamplifiers depending on make and model, including parts. Tube preamplifiers might cost more depending on the parts prices.  

Upgrade includes the following:

  1. Install IEC socket, replace with 16 AWG high quality wire.
  2. Install a premium AC line filter in line between the IEC input and the transformer.
  3. Replace all wire between power switch and the power supply with 16 AWG high quality low noise, high Q wire.
  4. Replace and upgrade the wires from the IEC to the Power supply PC Board with upgraded high Q wire.
  5. Replace critical audio path wire with upgraded high Q wire.
  6. Replace the RCA outputs and three RCA inputs with new high Q, gold plated Teflon RCA’s.
  7. Upgrade the internal wiring from the 22-24 AWG stranded copper wire between the RCA’s and the PC Board with 18 AWG low noise, high Q wire.
  8. Upgrade the internal wiring from the AC plug pins to the power supply and from the power supply to the preamplifier.
  9. Upgrade all 8 to 10 audio stage coupling capacitors with Reliable Multicaps.
  10. If a solid state preamplifier, upgrade the audio stage Op Amp IC’s with Burr Brown or similar quality, using a plug in socket so when improved Op Amp IC’s later become available they can easily be inserted.
  11. Upgrade the power supply capacitors with Blackgate capacitors.
  12. Upgrade the rectifier diodes with Fast Start Soft Recovery diodes (FRED’s).
  13. Clean the interior and exterior of the preamplifier.
  14. Test all the tubes if it is a tube preamplifier.
  15. Provide four 1inch adjustable gold plated pyramidal isolation feet to insure the proper tonal balance and to avoid the sonic modulation as a result of power transformer vibration.
  16. Provide an itemized list of parts replaced, including the replaced parts.
  17. If a tube preamplifier, provide tube ratings and before and after specs on the THD, S/N, and Channel Separation.

For those who recognize the benefits of balanced outputs and would like the gains associated with solving the ground loop problem by means of line out transformers, we can add two balancing transformers in line with the line outputs for $100.  If you wish new balanced outputs installed in addition so you have a true balanced output unit, add another $50.

For those who want an upgraded shielded High Q Premium AC Power Cord (see photo) as well as the Premium Package there is a $25 discount off the $175.00 Premium AC Power Cord. 

All upgrades are guaranteed, parts and labor, for 90 days.

If you have special requirements, please contact Joseph Chow by email at audiohorizons@yahoo.com .

All units to be upgraded must be in perfect working condition.  If repairs are required in addition to the upgrade, please indicate what they are before you ship the unit and we will discuss the cost of repair as an additional service. 

We are not responsible for units damaged in transit, so please package your unit carefully, remembering that we will return the unit to you in the same packaging. Damaged units will be returned freight collect.

Shipping including insurance in the continental US will be a flat $25.00. Canadians please email for S/H/I rates. Please contact us about the cost of S/H/I if you wish air shipment.

Payment for services must be made within 7 days of notice the work order has been completed.  We will ship the unit to you as soon as your funds clear our account.

Thank you for your interest in Tube Preamplifier upgrades by Component Plus, USA