The wonderful world of musical self-discovery... and a Gear question. :)

[Nadz1lla]

Hey all!

Over the last few weeks I've become increasingly happy with my rig. Since I bought my second-hand JCA20H from Ebay, I've not really had the chance to crank it due to my living situation. However, I started my new prog band about a month ago, and have been able to crank it at the practice room. WOW!!!

I am absolutely in love. After years of being limited to using my Pod or a friend's Valvestate (ugh... no offence to my mate but I hate the sound of it!) it's good to finally have an all-valve rig of my own.

My signal chain is currently: Guitar - Boss GE7 - Digitech Bad Monkey - Jet City JCA20H - Jet City JCA24S (the older, non-convertible version closed back).

It sounds absolutely killer, and I think it finally embodies "My" sound.

However, I can't turn the master up past 7, as the tone changes massively in the last three notches, thickening and warming up quite a lot. So I have been thinking of saving up for a 100w head for when we get to gigging. 20w is perfect for the practice room, but it'll quickly get swallowed up at a decent sized gig. I know most people get their cabs mic'd up, but I would feel a lot more comfortable with having that extra bit of headroom.

So I was thinking of saving for a JVM410h, because I really liked that sound when I tried one out a while ago. But then I got to thinking, if I like my Jet CIty sound, why not just try to get hold of a JCA100H? I mean it's basically the same amp, just more wattage (and based on the Soldano SLO 100, I might add!)

The problem is, they're very hard to come by in the UK now, so I've been looking at getting one from the U.S. If I order one from the U.S, is there anything I need to do to the power supply for it to take a U.K power-lead, or is it a simple matter of just swapping the U.S kettle lead for a U.K one? I know nothing about power ratings between different countries, so I didn't want to simply swap the lead, plug it in, and then have it burst into flames, hah!  :lol:

[Dmoney]

to use a USA one you'd need to use a stepdown transformer. An extra bit of kit you'd have to carry around that is super heavy, for turning 240volts (uk mains) into 120volts (US mains).

The other options is to swap the power transformer for something similar which is designed to run on UK voltage.

Given the cost of a second hand UK JCA100H, I'm not sure it would be worth importing one, paying for the amp, paying the customs fee and then getting the extra kit or the extra work done. 

[Dave Sloven]

I've imported a lot of stuff from the USA to Australia (e.g., pedals), but the one thing that I made sure of is that it can use the local power supply.  DO NOT waste your time and money on importing an amp like this and using a step-down transformer, especially with sound equipment.  Everything that generates a magnetic field will affect your sound somehow if anywhere near your rig, and these work really hard.

Also as stated above they weigh a ton.  My dad got one from someone and he used it for a while to run this old American-made 'hot knife' that I stupidly imported via mail-order in the 1980s. Eventually the soldering iron died.  We ended up giving away the transformer to a friend who collects gadgets, although given its weight my dad was being generous - the scr@p metal guy probably would have given him at least $5 for it.

You will find that amplifiers are generally built to run on either 100-120V or 220-240V, and will have a switch in the back to manage either end of that range. You would basically need to have a new transformer installed into the amp, and it would not be worth it.  Buy yourself a decent EQ pedal and use that to help you get the sound you want through an amp you can find in the UK.

[Toe-Knee]

(and based on the Soldano SLO 100, I might add!)

its actually a lot closer to the hotrod. I think you can still get the 100 & 100hdm from thomann fairly cheap. One thing to keep in mind is i've now had to repair 4 of these in the last year 3 of which had naff OT's the other was a switching issue.

 They aren't the most reliable amps imho. The 100HDM is more reliable than the 100h though.

[Nadz1lla]

Cool, cheers for all the info guys! I shall keep hunting for a U.K-usable one then, heh.  :lol:

[Nadz1lla]

(and based on the Soldano SLO 100, I might add!)

its actually a lot closer to the hotrod. I think you can still get the 100 & 100hdm from thomann fairly cheap. One thing to keep in mind is i've now had to repair 4 of these in the last year 3 of which had naff OT's the other was a switching issue.

 They aren't the most reliable amps imho. The 100HDM is more reliable than the 100h though.

Cheers dude, so I take it getting one from Thomann would require no further modification? Could you tell me what kind of mods I'd be able to get on these to make them more robust, if any? ALso, forgive my ignorance, but what's an OT? I'm having a special day today where trying to use my brain isn't really working, hah!

[Kiichi]

Cheers dude, so I take it getting one from Thomann would require no further modification? Could you tell me what kind of mods I'd be able to get on these to make them more robust, if any? ALso, forgive my ignorance, but what's an OT? I'm having a special day today where trying to use my brain isn't really working, hah!

If I am not mistake the OT is the output transformer.

[Toe-Knee]

(and based on the Soldano SLO 100, I might add!)

its actually a lot closer to the hotrod. I think you can still get the 100 & 100hdm from thomann fairly cheap. One thing to keep in mind is i've now had to repair 4 of these in the last year 3 of which had naff OT's the other was a switching issue.

 They aren't the most reliable amps imho. The 100HDM is more reliable than the 100h though.

Cheers dude, so I take it getting one from Thomann would require no further modification? Could you tell me what kind of mods I'd be able to get on these to make them more robust, if any? ALso, forgive my ignorance, but what's an OT? I'm having a special day today where trying to use my brain isn't really working, hah!

Kiichi was right meaning the output transformer.

The 100HDM is more robust in my experience the only issue ive come across with those was the switching but that was just one bad part which can happen to any amp really.

You can very easily get them modded to be closer to the SLO if you so wish and its not a massively invasive job but it still isnt quite the same but a lot closer.

for what its worth i've also seen someone having to replace the power transformer on a JCA50H.

[PhilKing]

I've noticed that a lot of Jet City's have multi tap transformers and can work on many voltages just by switching.  If you check for this you won't need to do any mods, other than probably changing the mains fuse and moving the switch - this one does http://www.ebay.com/itm/Jet-City-JCA100HDM-Amp-head-ALL-TUBES-NEW-/330734073844?pt=LH_DefaultDomain_0&hash=item4d014977f4

so does this 50:
http://www.ebay.com/itm/Jet-City-JCA50H-50w-Tube-Guitar-Head-/271217878622?pt=LH_DefaultDomain_0&hash=item3f25d8665e

[Nadz1lla]

You can very easily get them modded to be closer to the SLO if you so wish and its not a massively invasive job but it still isnt quite the same but a lot closer.

I meant more in terms of the OT itself, but you said someone had to replace the OT in a JCA50H, so I guess that answers it, heh.

The OT is simply the actual electrical supply part of the amp, right? In that case, would it be easy enough just to swap out the Jet City one for something that is more reliable, say from a Marshall? Or is it more complex than that?

Sorry for all the questions, I just think I should stay with Jet City if I like the sound so much (and FAAAAAR cheaper than a Marshall, too, heh), but want to be sure I can swap out any weak / unreliable parts for more robust and reliable parts if I go down that route eventually.

Just saw the JCA100HDM / JCA24S bundle on Thomann which looks like a really good deal, would also mean I can have two cabs in stereo, one of which would then also be the convertible one so I can have even more sound-shaping options.

I think I'm getting a little over-excited, hah! :D

I've noticed that a lot of Jet City's have multi tap transformers and can work on many voltages just by switching.  If you check for this you won't need to do any mods, other than probably changing the mains fuse and moving the switch - this one does http://www.ebay.com/itm/Jet-City-JCA100HDM-Amp-head-ALL-TUBES-NEW-/330734073844?pt=LH_DefaultDomain_0&hash=item4d014977f4

so does this 50:
http://www.ebay.com/itm/Jet-City-JCA50H-50w-Tube-Guitar-Head-/271217878622?pt=LH_DefaultDomain_0&hash=item3f25d8665e

Cheers dude, that looks very hopeful! If it's that simple, then that's a pretty awesome feature for a "lower-end" amp. Pretty impressive! It's all in the details, people! :D

[Toe-Knee]

You can very easily get them modded to be closer to the SLO if you so wish and its not a massively invasive job but it still isnt quite the same but a lot closer.

I meant more in terms of the OT itself, but you said someone had to replace the OT in a JCA50H, so I guess that answers it, heh.

The OT is simply the actual electrical supply part of the amp, right? In that case, would it be easy enough just to swap out the Jet City one for something that is more reliable, say from a Marshall? Or is it more complex than that?

Sorry for all the questions, I just think I should stay with Jet City if I like the sound so much (and FAAAAAR cheaper than a Marshall, too, heh), but want to be sure I can swap out any weak / unreliable parts for more robust and reliable parts if I go down that route eventually.

Just saw the JCA100HDM / JCA24S bundle on Thomann which looks like a really good deal, would also mean I can have two cabs in stereo, one of which would then also be the convertible one so I can have even more sound-shaping options.

I think I'm getting a little over-excited, hah! :D

I've noticed that a lot of Jet City's have multi tap transformers and can work on many voltages just by switching.  If you check for this you won't need to do any mods, other than probably changing the mains fuse and moving the switch - this one does http://www.ebay.com/itm/Jet-City-JCA100HDM-Amp-head-ALL-TUBES-NEW-/330734073844?pt=LH_DefaultDomain_0&hash=item4d014977f4

so does this 50:
http://www.ebay.com/itm/Jet-City-JCA50H-50w-Tube-Guitar-Head-/271217878622?pt=LH_DefaultDomain_0&hash=item3f25d8665e

Cheers dude, that looks very hopeful! If it's that simple, then that's a pretty awesome feature for a "lower-end" amp. Pretty impressive! It's all in the details, people! :D

Oh you can definitely swap the OT out. There are some fantastic Soldano replica transformers on the market ranging from £70 to £250 depending just how high quality you want to go.

The output transformer determines a pretty good portion of the sound of an amp. A great output transformer can make a mediocre amp sound incredible. However sometimes a great transformer can highlight negative aspects of amps too that the original transformer didn't reproduce.


One thing to keep in mind though is depending on the current prices of the jet city 50/100w amps you may only be looking at a couple of hundred more to just buy a proper SLO clone.

[Dmoney]

http://www.ebay.co.uk/itm/JET-CITY-JCA100H-/281085878357?pt=UK_MusicalInstr_Amplifiers_RL&hash=item4172062055

That looks like a deal.


The Output Transformer is responsible for sending your output to the speakers. It's the Power Transformers that is responsible for providing all the voltages to make the amp work. It's not that simple to swap the PT, because you need to use one that will supply all the correct voltages (it's not 240volts in and high voltage out, its more like 240volts in and bunch of different voltages rated to run different circuits out) and this makes it a little complex.

swapping the OT is a little more simple. Like Tony says, there are a lot of off the shelf options.

and to get a stereo rig you'd have to use it with your JCA20. 2 cabs into one head is still mono unless you have a stereo head, and most heads aren't stereo.

If the OT's go a lot, I'd be inclined to wonder what valves they ship with and if beefing up the screen grid resistors would be a low cost way of making the amp more reliable. I didn't realise they had issue. I thought they'd be solid.

[Nadz1lla]

Ah I seeeeee! Ok thanks guys, gives me a lot to think about. The plot thickens!  :lol:

[ericsabbath]

the jca20h sounds huge with the master around 4-5, specially with v30's
past that, the el84's start to compress way too much for my tastes

why not considering a 50 watter instead of a full 100w?

[Nadz1lla]

I guess because the next head I get I want to be able to cover me for most situations. That JCA100HDM has a switchable 50w mode, which makes it quite versatile as it covers the two major wattages above my existing amp.

Also regarding the Marshall I was looking at, I can get a really nice tone out of that at around a third to half volume too, which again would be a great quality for me.

Decisions....  :?