My personal reference modded Parasound JC-1 monoblocks for sale - SOLD

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audioengr


I used these at multiple shows where my system got best of show.  My front end and these amps were the reason I got best of show. Silver color. They beat other monoblock amps costing much more.  They crush Levinson, Krell, Pass Labs, Classe and others. They are in the league with D'agostino amps.  The output impedance is extremely low due to all of the output transistors, so they drive virtually any speaker load.  If your speakers are 4 ohms, these will give you about 1000W per side.   They will drive any ribbons or electrostatics.  I am only selling them because I have converted to SET tubes and have more efficient speakers being built.

The mods make a HUGE difference in these amps.  I have multiple customers raving about them and I can put anyone interested in contact with these customers.  These amps have more jump factor (dynamics) and better bass control than 99% of amps on the market.  They also deliver the detail and finesse that very few amps can do with an airiness that most amps dream of having.

New retail pricing on these amps is $9K and the mods for two of them is $4K.  IF you purchased a used set in good condition for around $5500 and then added the mods, it would cost you $9500 plus shipping with 3-4 month lead-time.  This is a one-time opportunity.

I am willing to let this set go for $7500 plus shipping, a $2K savings over the best case scenario.

Steve N.
« Last Edit: 24 Apr 2016, 08:16 pm by audioengr »

audioengr

Re: Amazing modded Parasound JC-1 monoblocks for sale
« Reply #1 on: 7 Mar 2016, 08:22 pm »
Here are the mods details and a review:

The stock JC-1 monoblocks sound a lot better than most amps in their price
range, however there is a lot more performance potential locked-up in
these amps. Their primary weakness is dynamics, particularly in the
high-frequencies. They also tend to be a bit muddy in both the midrange
and highs due to their power delivery topology, even though they
deliver the detail in spades right out of the box, or at least after a
month or two of break-in. This muddiness can best be described as a
bit of congestion or compression. They just do not open-up and envelope
you in an unrestrained, spacious soundfield.  The "air" is missing.

The EA Turbomod removes all of these weaknesses. It transforms the
JC-1's into spectacular, breathtaking music machines. The soundstage
doubles in width compared to the stock amp and the slam factor improves
by an order of magnitude. The weight, authority and richness of the music
is improved dramatically. There is a spaciousness of the sound field that
just immerses the listener. The focus of violins, violas and cellos is razor-
sharp, but with finesse and sweetness, not harshness. Transient response
is improved so that percussion, such as drums, cymbols, bells and
vibraphone have real attack, sustain and decay. The front-to-back layering
is so detailed that the relative positions of different instruments can be
sensed within a few feet. Most first-time listeners believe they are listening
to surround-sound, when it is only 2-channel. We believe that this is the
best-sounding SS amp on the planet. We recommend that the JC-1's
be run balanced for best performance.

The amplifier mods include:

- Power delivery improvements to the driver boards, including Black Gate capacitors
- Perfect Crystal silver harnesses for the driver to main boards
- 12 New power harnesses - this replaces the stranded copper with PVC insulation wiring in the amp with solid-core multiple twisted pair copper with silver plating and Teflon insulation.  Even your $50K amps don't have this.
- Power topology changes to both driver and main boards to force the currents to run in more optimum paths (most amp designers don't give this any thought -  :scratch:)
- Power delivery improvements to the driver boards, including Black Gate
capacitors (there are no Black Gates in the stock amp)
- Perfect Crystal silver input wiring from XLR's and RCA's - your $50K amps don't have this either
- Disabling of the "auto-power-on with signal presence" to simplify and make the input wiring lower capacitance
- Removal of some filtering and upgrade of other filter caps
- Check adjustment of low and high bias and match between the monoblocks - this is usually out of adjustment or set too high in these amps - replace the pots with better ones
- Replace the 8 small inrush limiters with much larger heavy duty ones - these are marginal at best and often blow-up in the stock amps  - have seen pieces blow off of them when you power up
- Resolder all of the power output transistors - these manual solderers just do a poor job, resulting in resistive solder joints
- Replace 10 International Rectifier Mosfets with Fairchild Mosfets - this was recommended by Bob Crump and John Curl
- Replace the main voltage dropping resistors on the input boards with 8 thick film low-inductance types - to reduce resistor thermal noise and eliminate inductance in this power path

Reviews:
http://forum.audiogon.com/cgi-bin/frr.pl?ramps&1119985513&read&3&4&

"I know many of you have been waiting for this review…so thank you for your patience.
I wanted to make sure I had a grip on exactly what changed and how it changed
from the stock JC-1's prior to writing this review. Lets start with what remained the
same. The bass is just as I remember it. Tight, tuneful, and just right! I did not
detect any major change in respect to bass authority or control. The stock JC-1's
were already great in that respect. The sound stage grew a little in width but the
increase in size for me was not substantial. The soundstage depth however did
improve to a degree worth noting (which I attribute to the mods improvement in
midrange clarity…but I will get to that in a moment). The stock JC-1's throw a huge
sound stage so I was not looking for much improvement here. So, enough about
what the mod did not do…let's talk about what it did do. The midrange..oh..the
midrange. This was my biggest complaint with the stock amp. The midrange seemed
constricted and slightly closed in compared to a great tube amp (or even a solid state
one). It was almost as though a slight haze existed over the midrange and as a result
a little bit of natural bloom and clarity was missing. This is no longer the case. The
midrange is as clear as I have ever heard in my system and substantially more so
than it was with the stock JC-1. Voices and instruments have a clarity that was missing
with the stock amps. The amp just opens up in the midrange and lets you here every
detail. It sounds as though the amps transparency has been greatly improved! More
to the point, a smoothness exists in the midrange where it did not before. Imaging is
now pin point accurate (and to be honest, it was very good before). Everything just
sounds more real! It is simply a joy to listen to! The attack and decay of the treble
also improved to a great degree. The treble seems to extend higher then it did before
and has a shimmer and clarity to it that was not apparent with the stock amp. I believe
that the additional treble extension also adds to the amps newly found transparency.
While I would not say that the amps weight and authority have improved substantially
(again they were great to begin with), I would say that the treble attack provides for
somewhat better dynamics than the stock amp. Guitar plucks just hit and pull back
with a speed they did not before without loosing any of the instruments body! So, let's
recap. Midrange openness, midrange smoothness, overall transparency, imaging, and
treble extension are where the magic lies with the Empirical JC-1 Turbo Mod. I know
you are going to ask, so the answer is a resounding YES!!!!...it is worth the money! Is
it the best amp on the planet after modding?..probably not. But it would take you an
awful lot of money to do better. I have heard a number of the super amps out there
(not all of them of course) and none that I have heard would embarrass the modded
JC-1's.

Daniel H."
« Last Edit: 8 Mar 2016, 01:25 am by audioengr »

7ryder

  • Jr. Member
  • Posts: 10
Re: Amazing modded Parasound JC-1 monoblocks for sale
« Reply #2 on: 9 Mar 2016, 05:27 am »
I had a pair of these amps and wholeheartedly agree with Steve's description of these amps. Get 'em while you can!

ChrisG

mtruong34

Re: Amazing modded Parasound JC-1 monoblocks for sale
« Reply #3 on: 9 Mar 2016, 09:09 am »
Are these your personal amps or only used for shows?

audioengr

Re: Amazing modded Parasound JC-1 monoblocks for sale
« Reply #4 on: 9 Mar 2016, 08:08 pm »
Are these your personal amps or only used for shows?

Both.  The last couple of shows I used tubes provided by another vendor and once I used a SS provided by another vendor at Newport.  Really problematic.  Before that I used these.  Always worked perfectly and performed outstanding.  These are solid.  I would expect to use them for another 20 years without issues. 

The only thing you have to avoid is shorting the outputs while playing music, but that is the case with any amp.  They have protections for this, but these circuits can be a bit slow-responding.  May or may not protect it from a dead short.  They really protect well from DC offset from the preamp or DAC.  Most amps just fry.

Steve N.

audioengr

bump :D

Rocket_Ronny

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They look tasty. Someone is going to get some nice amps.

Rocket Ronny

audioengr

They look tasty. Someone is going to get some nice amps.

Rocket Ronny

That's for sure.  I am selling them reluctantly because they have served me so well.

Steve N.

tpaxadpom

  • Jr. Member
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If anyone is looking for 1 Parasound JC1 with Empirical Audio mod, let me know.