JCA Owners!! Join the Jet City Lounge!!

[GRIMESPACE]

 

Originally Posted by KENNYKING1965

Got 2 2x12 cabs at 8ohm a piece. Would these be connected to 4ohm speaker outputs? One has vin 30's other g75t's [JCA 50H]

 

Yep - exactly right. Jack pairs are wired in parallel.

[sahlomonic]

Little speaker preference update here. V30s seem to be the go to choice, but after today I have a new favorite. Played my JCA100H through KCTigerChief's Mesa-style 2x12 loaded with Weber FC12s, and HOLY {censored}BALLS. I tell you, V30s take a back seat next to these Fane clones. Brought out a damn fine Marshall vibe and a lot of warmth I couldn't quite get with V30 style speakers.

Definitely try a pair.

[Gwimlock]

 

Originally Posted by sahlomonic

Little speaker preference update here. V30s seem to be the go to choice, but after today I have a new favorite. Played my JCA100H through KCTigerChief's Mesa-style 2x12 loaded with Weber FC12s, and HOLY {censored}BALLS. I tell you, V30s take a back seat next to these Fane clones. Brought out a damn fine Marshall vibe and a lot of warmth I couldn't quite get with V30 style speakers.

 

I've recently switched to a new primary cabinet, a Whitebox 2x12 loaded with Lynchbacks. The thing blows me away. Definitely warmer, smoother than the H30/V30 combo I was running previously with my JCA50H. (Was sporting twin V30s before and the high-end was causing so much ear fatigue, but this was before I changed out the crap stock tubes.) While the bass and upper mids are more organic than the V30s, I do find myself missing the high-end sizzle of the V30s... somewhat. The V30s are much more direct and aggressive. Is one better than the other? I haven't had enough time with the LBs to really say, but I'm pretty sure that I'd choose the LBs over the V30s most of the time.

So in my limited experience, JCA50 + V30s = searing, punchy 80's rock, while JCA50 + Lynchbacks = huge and blooming, more vintage/indie-ish.

If any of that makes any sense...

[university81]

Made a few videos of a recently aquired JCA50h , lovin the amp so far =0 figured i'd post them in here if anyone's interested

Changed the faceplate and tubes -- the amp is otherwise stock

for the faceplate i just took the existing Jet city faceplate, got it measured in a hardware store and got a piece of walnut wood/furniture fittings cut to size (i picked a piece of walnut for the tonal qualities it would impart on the amp ofc

 

 

 

[Neilrocks25]

from another thread

I did a clip of my Jet City 20w combo with some pedals, I cranked it to band practice volume.

Mt first clip since I added a depth mod. The Depth mod is fun, you get that thump you get with a 4x12. (well kind of)

I thought the camera shacking at 1:45 was great, it was pretty loud and not a big room, the low end was great for a small 20w combo

* Disclaimer* The play is sloppy blah blah and all that bollocks (the g string might be a little sharp due to the humidity, but my playing sucks so who cares)

 

 

 

 

 

 

 

Jet City JCA2112RC combo with depth mod (Turned up to about 2 O'clock) I am also using an MXR Carbon Copy delay, an SD-1 with a Monte Allums GT mod I added (fantastic mod I really recomend) and a Black russian Big muff I modded (added a mid control and some other mods) the volume was about 4 or 5 and very loud in the room, loud enough to play with a drummer.

I used an Edwards Les paul copy, and a little chorus on the first couple of chords.

 

 

 

 

[Edge11]

 

Originally Posted by university81

Made a few videos of a recently aquired JCA50h , lovin the amp so far =0 figured i'd post them in here if anyone's interested

Changed the faceplate and tubes -- the amp is otherwise stock

for the faceplate i just took the existing Jet city faceplate, got it measured in a hardware store and got a piece of walnut wood/furniture fittings cut to size (i picked a piece of walnut for the tonal qualities it would impart on the amp ofc

 

 

 

 

That looks sweet, how much did the walnut run you?

[Yarbicus]

Just a heads up:

1. For limited time, if you buy a new JCA22 combo you get a free Flood delay pedal

2. The JCA20HV ("vintage" clean) is now in stock

3. The vertical 2x12 with V30s is now in stock

Dang, but I want one of those vert 212!

[Postal69]

Hi,

Recently purchased a JCA50H and love it...

How do I join this club?

[Yarbicus]

 

Originally Posted by Postal69

Hi,

Recently purchased a JCA50H and love it...

How do I join this club?

 

I think you just did!

[Ovid9]

 

Originally Posted by Yarbicus

Just a heads up:

1. For limited time, if you buy a new JCA22 combo you get a free Flood delay pedal

2. The JCA20HV ("vintage" clean) is now in stock

3. The vertical 2x12 with V30s is now in stock

Dang, but I want one of those vert 212!

 

Where are these things in stock at Yarb?

[Yarbicus]

 

Originally Posted by Ovid9

Where are these things in stock at Yarb?

 

I think that they are available direct from JCA. Whiteboxeng.com also sells some products. If you really want one, PM me and I will get in touch with Doug and find out for you.

[Postal69]

 

Originally Posted by Yarbicus

I think you just did!

 

Too easy. Thank you.

[Neilrocks25]

what speaker should I get to replace the enimence (it sounds a bit like some one has put a blanket over it) not too harsh and I like mids.

JCA2112 20w combo

I have modded mine a bit already, depth mod, clean switch and cap on the feedback resistor (R12, to tame the highs a little)

[Ovid9]

 

Originally Posted by Yarbicus

I think that they are available direct from JCA. Whiteboxeng.com also sells some products. If you really want one, PM me and I will get in touch with Doug and find out for you.

 

Did not realize you could buy direct from JCA. That's cool!

I'm good on gear for the moment (hah, who am I kidding?) but sooner or later, something of theirs will be mine. Oh yes, it will be mine.

[Yarbicus]

 

Originally Posted by Neilrocks25

what speaker should I get to replace the enimence (it sounds a bit like some one has put a blanket over it) not too harsh and I like mids.

JCA2112 20w combo

I have modded mine a bit already, depth mod, clean switch and cap on the feedback resistor (R12, to tame the highs a little)

 

Mike Soldano himself has fallen in love with the JCA sound and the Vintage 30.

[Boffo]

Hi, all.

This is my first post here on this forum. I gather that I now have just become a member of the Jet City Amplification club after the purchase of a JCA amplifier.

I managed to get a JCA5215RC at huge discount because it was faulty; the clean channel would not switch in. That problem was easily diagnosed and repaired; cracked solder joints on PCB mounted socket, not an uncommon occurrence when straight plugs are used.

However, with the above mentioned problem being solved, it still didn't sound right; it sounded dull and quiet for a 50W valve amplifier.

After a few minor tweaks and mods the amplifier is sounding much better.

I did some further tracing of the printed circuit board, only to discover what may be some fairly significant manufacturing flaws. I have done some temporary rectification work in a way to which I would normally build an amplifier.

Searching the internet for information about the JCA5212RC circuit design has not resulted in any information at all about the problems that I see.

Nor has the results come up with any schematic drawing of the amplifier, so I can check it against the circuit board.

Does any one here know where, or how, I could get a copy of the schematics ?

But other than that, the amplifier is sounding fantastic; will sound even much better once the speakers have been broken in, of course .

Now... what to do with that spare 12ax7 triode? Has the mind thinking.

Thanks for listening

[Herptheflerp]

Boffo there is another thread on this forum for modders of the JCA line, find it, I think there are some schematics there. What design flaws did you find if you don't mind me asking?

[Herptheflerp]

Found a link boffo, search around ths thread.

http://acapella.harmony-central.com/...nd-owners-club

[Neilrocks25]

Something I found today, I have never been happy with my 20w combo's harshness at higher volumes. Ice pick is a word that fits this amp.

I have modded it a few different ways but it always sounds a bit to much muffled for my taste, with the mods.

So I found if I lowered the treble to around 8 or 9 o'clock and raised the mids to 2 or 3 o'clock and left a little presence, it sounded much better. and mixed with the depth mod it really sounds good at louder volumes.

I had a lot of fun with it today.

[sahlomonic]

 

Originally Posted by Neilrocks25

Something I found today, I have never been happy with my 20w combo's harshness at higher volumes. Ice pick is a word that fits this amp.

I have modded it a few different ways but it always sounds a bit to much muffled for my taste, with the mods.

So I found if I lowered the treble to around 8 or 9 o'clock and raised the mids to 2 or 3 o'clock and left a little presence, it sounded much better. and mixed with the depth mod it really sounds good at louder volumes.

I had a lot of fun with it today.

 

The Eminence speaker in the Jet City amps are supposedly very neutral sounding. Since you're using the stock speaker, I'd suggest a V30. Oddly a lot (well a lot on the internetz) complain of the ice picky sound of the V30, but I've never experienced that with my JCA, and I think a lot here would concur. I can also vouch for a Weber FC12 (Fane clone) and the Celestion Lynchback (my fav).

[Boffo]

Yes, thankyou, Herptheflrep.

I did find that thread fairly useful as some of the component values suggested I used to mod my JCA5212RC.

However, the JCA5212RC circuit is very different to any of the other Jet City amplifiers, so the schematics posted on that thread are of limited value.

I would hazard a guess that the JCA5212RC is much closer in design to the Soldano "Lucky 13" circuit ?

As for the flaws that I think exist, I don't wish to post here prematurely before I have had a chance to thoroughly investigate the schematic and try to understand the reasoning behind the design. But to give a little clue; one flaw is in the input stage; another is in the FXR stage.

[sahlomonic]

Alright I gotta post this one. Vid of our show the other night with a new drummer. Stock JCA100H with worn out tubes going into my Avatar 2x12 with Lynchbacks, and a stock PRS SE245. We've recorded several of our gigs but this one has the best quality IMO. Other than full tilt stage monitors getting me lost a few times I'm happy with the our set.

[Boffo]

After a bit more investigating, I have come to the conclusion that the FX-loop is most likely correct as per design. The major difference in the design of the JCA5212RC to all other Soldano designs is that: the FX-loop is integrated with the reverberation driver and recovery stages; and, that the FX-send is driven by a "common cathode" triode stage(anode follower), where as all other designs a driven by a "cathode follower". The closest design I could find would be the Yamaha T50/100 amplifiers.

Whilst it may be unique in design, I'm, not fully convinced of its effectiveness, as I think it is too susceptible to picking up EMI/RFI .

Anyway it's a pity that not many people are discussing the JCA5212RC, I think this amp is could be a modder's playground, esp. with the spare triode. ???

Cheers

[Yarbicus]

Just wanted to let you all know that American Musical Supply has the new JCA20HV and matching vert slant 2x12 on their website now.

http://www.americanmusical.com/ItemS...t-City--page-2

[koen77]

just did the depth mod on my jca 100 myself. Disconnected the feedback wire, put a 1kohm pot and a resistor in between and reconnected to the 4 ohm tap. It fills out a bit but is not really spectacular, especially at higher volumes.I just turn it on a bit and pull the bass knob back, i like it, but it's not mindblowing. I got all the information from your great thread and am kinda proud I did my first amp mod. Cheers !