TGP Review by SCMAVL
https://www.thegearpage.net/board/index.php?threads/jca-circuits-golden-ratio-1-6.2529034
“After much mental back and forth, I’ve decided to let this stellar – and RARE- amp find a new home. I’ve had the good fortune to own Dumble, Ken Fischer, and Jim Kelley amps and I can honestly say this amp deserves to be in the same discussion as those.
Jason C Arthur (JCA) was a protégée of Ken Fischer (Trainwreck) in the 1990s. He built 12-14 of these amps back in the mid-’00s that are unlike anything else I’ve ever played. The MOST touch sensitive amps you can imagine. 9-10 years ago, I was able to buy the #1 Golden Ratio 1.6 from the builder who’d kept it as his personal amp since it was built. That was the actual amp that was sent to the ToneQuest Report and garnered a glowing review. I later was able to acquire this one as well, the only difference being the speaker and faceplate color. The #1 amp now lives with a good friend of mine, and I’ve babied this one for awhile now.
Being so few of these in the world, and owing to the fact that they came out prior to the days of YouTube gear reviews, there are virtually no clips online. But there are plenty of glowing reviews, from the aforementioned 2008 ToneQuest Report to a handful of folks of this forum who have tried one. The vibe of this amp is influenced by Trainwreck, as it’s got plenty of gain on tap and cleans up better than anything else with the volume knob. But it reminds me very much of a Jim Kelley in the way it sustains and has lots of tweakability with the switches, trim knob and EQ. It’s been referred to as a “Dumble Killer”, although I don’t think that’s accurate, unless you’re talking about an Ultraphonix Dumble. The trim knob let’s you tighten it up like a proper hotrodded Marshall or get a bit looser and fatter like a tweed (switched to Hi Tilt and Plush) or a Vox (when switched to Lo Tilt and Lean). Being a 6V6 amp, the cleans are pretty Fender-y but with slightly more prominent midrange. It’s a room-filling 20 watts, with a very full low end…
I spent quite a bit of time swapping NOS tubes in the amp to find the ones that I liked best in it. I settled on a pair of Sylvania 6V6s and a 5751 in v1 (after trying over a dozen NOS in it). It’s cathode biased, so tube swapping is easy nd does not require biasing. It’s also got a NOS Sylvania 5Y3 rectifier. I’ve tried different speakers in it and landed on this Celestion G12C, a rare one only available in two discontinued Marshall 4x12s (one was the crazy expensive Hendrix full stack reissue).
So if this amp is so amazing, why am I selling it? I’m a longtime punk rock and rockabilly guy, usually a frontman/rhythm player (when I’m not playing drums for other folks). I don’t need -or deserve- an amp that can do what this one does. I’ve got a handful of amps and lately just find myself plugging into an old JCM800 and banging out The Buzzcocks or The Pixies. I’d love this to go to someone who will appreciate the nuance and possibilities it offers.
I’m not sure what to ask for this. The last one that sold on Reverb had an asking price of $35,000 and the one before it was $25,000. But that seems excessive. I’d think something in the neighborhood of $6500 is more reasonable…” SCMAVL
TGP Review by nbessie1
“The very first JCA Circuits GR 1.6 that started the legend! This is that amp!
I can’t believe I found this amp (during COVID) and I can’t believe I’m selling it now (but it needs to happen).
The best way to describe the amp is to read the TONEQUEST REPORT review:
…it says it better than I ever could and, if anything, I think TONEQUEST understated how great this amp really is!
A true one-of-a kind amplifier!
I currently have the amp loaded with some great NOS tubes and will include those in the sale (if you have your own tubes and want the amp without tubes we can work that out too).
There’s been a LOT of talk/hype lately about what these original-run JCA GR 1.6 amps are worth and it’s been kind of crazy!
I’m pricing this one at $6500 shipped (USA only).”
TGP Review by pima1234
“For me, there was nothing like the JCA Circuits GR 1.6. Just a spectacular combo amp, with all the right knobies and switchies. I was a complete idiot to sell it.” pima1234
TGP Review by highgeer
https://www.thegearpage.net/board/index.php?threads/price-drop-jca-circuits-golden-ratio-1-6.2156436
“This is a rare bird.
The JCA Circuits GR 1.6 was made by Jason Arthur with collaboration from Ken Fischer. This is essentially a 20 Watt 2-6V6 Trainwreck combo; pretty much sounds like a 20 watt Komet.
Meticulously built with the best components. I Have included a photo of the 2007 Tone Quest report of this very amp. A lot of amp in a great little package. Amp is in excellent condition both cosmetically and functionally.
The GR can serve as a small grab and go pedal platform, but it becomes a fire breather as you turn it up.” highgeer
TGP Review by nbessie1
Wow!…I wish more people could have these amps (because they are so great!)…I wish there were more of them in the world!
I’m lucky enough to have two of them!
(including the one (#1) that the OP had (with the letter from Jason) that ToneQuest reviewed).
I got my first one in a trade from a friend here on TGP and loved it so much I immediately started looking for a second one! (which, amazingly, I found by coincidence in three days!)
These are great, great amps!
If you ever see one for sale, buy it!…you won’t regret it!
Everything that ToneQuest says about the JCA GR 1.6 is correct….it’s literally the best small combo amps I have ever had!” nbessie1
TGP Review by Baemer
“Up for offer is an incredible combo amp. The amp that garnered the glowing review in the Tone Quest report, linked to below. Jason Arthur (JCA) studied with Ken Fischer and his amazing design makes this clear. The JCA has been played by folks with some incredible ears and chops, who had input in the final design as available here, including making the recommendation to have this Celestion Blue re-coned with hemp by A Broun Soun in San Rafael, CA.
Review of this particular amp is available here – https://web.archive.org/web/20091222041956/http://www.jcacircuits.com/ToneQuest.pdf
Very few in existence – dual 6v6, flavors of Trainwreck Rocket, Tweed Deluxe, and Fender Blackface Deluxe. Highly touch sensitive, truly amazing clean sustain and bloom. Chimy clean to mean all controlled via guitar volume.
It’s too loud for my current needs (singer/songwriter pop band, and a duo with wife). If I can find a better fit for this amp, I’ll pull the ad, as it is incredible and one of a kind.” Baemer
TGP Review by Baemer
“Hi Guys –
I just picked up the amp reviewed in the article below in a trade.
The only changes made to it since the review is that the speaker has had a hemp re-cone on the Celestion Blue.
It’s really a super inspiring beast to play, and I’ve been very happy with so far, I feel it is upping my game due to the touch responsive qualities and the fact that you play it as well as your guitar, putting you in an ‘inspiration loop’…it gives back everything you put into it. Massive sustain, uber thick cleans, plenty of gain available if you go there, very transparent, bloomy and chime-y. Reminds me of a Trainwreck Rocket style amp I once played.
Why are these so under the radar? What happened to the builder? Any other owners out there? I found a Facebook page with 4 members, and that’s about it for current active users.
If you have knowledge, or own or have owned one, please share your stories!” Baemer