GO-NAD!

[misterwhizzy]

Re: GO-NAD!

As for biasing, this is probably the best resource I've found.



Now, as for the depth mod, it gives you a way to control the bass on the amp. No, for real. Not like the useless bass knob on the front of the amp. It provides control over the bass passed through the power amp. I wish I had a way to describe it. I'll do my best here.

Stock, the bass control acts sort of as a fullness knob. You want a thicker tone? You increase the bass. You want it thinner and crunchier? You knock off some bass. But to my ears, it didn't really affect the frequency response of the amp. It's not like turning up the bass makes the overall frequency response bassier. It just makes it muddier or cleaner, to some extent. Does that make sense? Play with the knob for a while, and see if you understand what I'm saying.

Now, enter the depth mod. It will put another knob on the back of the amp that controls what the bass really should be doing. And it actually works. I found a sweet spot at about 7 o'clock (because I put the pot in upside down, it runs from about 1 o'clock to 11 o'clock). The sound is nice and full, with defined bass. It really puts the control of the power amp into your hands in a way the presence knob does not. If you don't care about reselling the amp, do this immediately.

I put a choke in mine too, but honestly, I don't know if that was worth the time or effort. It may have tightened up the bass a bit, but it also may have thinned out the tone a tiny bit too. By the way, as a point of reference, I get basically Megadeth Rust in Peace levels of gain with the knob around 7. And I think I may have biased mine to about 20 mA. That does sound about right.

 

[USAPatriot]

Re: GO-NAD!

As for biasing, this is probably the best resource I've found.



Now, as for the depth mod, it gives you a way to control the bass on the amp. No, for real. Not like the useless bass knob on the front of the amp. It provides control over the bass passed through the power amp. I wish I had a way to describe it. I'll do my best here.

Stock, the bass control acts sort of as a fullness knob. You want a thicker tone? You increase the bass. You want it thinner and crunchier? You knock off some bass. But to my ears, it didn't really affect the frequency response of the amp. It's not like turning up the bass makes the overall frequency response bassier. It just makes it muddier or cleaner, to some extent. Does that make sense? Play with the knob for a while, and see if you understand what I'm saying.

Now, enter the depth mod. It will put another knob on the back of the amp that controls what the bass really should be doing. And it actually works. I found a sweet spot at about 7 o'clock (because I put the pot in upside down, it runs from about 1 o'clock to 11 o'clock). The sound is nice and full, with defined bass. It really puts the control of the power amp into your hands in a way the presence knob does not. If you don't care about reselling the amp, do this immediately.

I put a choke in mine too, but honestly, I don't know if that was worth the time or effort. It may have tightened up the bass a bit, but it also may have thinned out the tone a tiny bit too. By the way, as a point of reference, I get basically Megadeth Rust in Peace levels of gain with the knob around 7. And I think I may have biased mine to about 20 mA. That does sound about right.

He's kind of hard to understand but I'll take notes and see if it makes sense to me that way. Probably be best to be looking at the board when I take the notes too.

Yeah I get it about the EQ. Most of them seem to be pretty ineffective, but that's why we tweak I guess. Depending on the tube swap, I may or may not do the choke...I'd seen that one. Until I get the tube issue sorted out it's all just wait and see as far as mods go. I don't use a lot of bass...probably because even the B/S gets a bit muddy, so my music sort of takes what the amp and GT-10 can do and fits within those parameters. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

How do you use the GT-10? Does it provide the dirt, or just modulation and delay type of effects? And please keep me posted on the Zero Loss FX Loop. If you get that done properly, I may give it a shot. But I just don't use many effects when playing dirty. Anything else can go into the front of the amp.

 

[USAPatriot]

Re: GO-NAD!

How do you use the GT-10? Does it provide the dirt, or just modulation and delay type of effects? And please keep me posted on the Zero Loss FX Loop. If you get that done properly, I may give it a shot. But I just don't use many effects when playing dirty. Anything else can go into the front of the amp.

I pretty much just use the GT-10 for the effects as most of the preamps just blow. The two patches that I do use that use the GT's preamp are both cleans and both based on the 1959 Marshall. Otherwise I've just been using the HT-40's preamp. I'm using 4CM...or have been mostly. Sometimes I just run a cable from the GT-10's Send to the HT-40's Return and leave it at that.

More than likely the Zero Loop isn't going to happen as there's been a change in plans. As of midnight last night, JCA was going to send me new tubes, which was kind of them, then this morning they decided they'd rather have me send the amp to them, which would have been cool but they wanted me to pay the shipping. So I sent in a request to AMS for an RA# to return the amp direct to them in return for a JCA22H...which of course removes the need for the ZL loop. I'm not sure how the cost breakdown will land as I bought the half stack plus an extra cab but am just returning the head. I'd guess they'll just credit me for the cost of the 20 if bought alone so I should get the 22 for about $120. Too bad the 22 doesn't also have a reverb, but oh well. The GT has plenty. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

All right, well please give a review of that head when you get it. I always like opinions on this stuff. I can't help you with that one as much, but I'm still very interested.

 

[USAPatriot]

Re: GO-NAD!

All right, well please give a review of that head when you get it. I always like opinions on this stuff. I can't help you with that one as much, but I'm still very interested.

You can count on that I'll play it for a week before I take it apart to get photos and try to see what makes it tick. I don't know if the JCA20 is in there with the added tubes and loop or if it's an entirely different design all around. Crud, I should have gotten pics of the 20 before I packed it up. Oh well. Just waiting on approval from AMS on the swap. Thanks for all your help. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

As I understand it, the JCA22H incorporates the JCA20H crunch channel along with the SLO preamp as a second channel. It then runs through a serial loop into the same power section as the JCA20H. So it adds all the stuff I want and nothing I don't. I just don't want to buy another amp that's nearly identical to mine.

Oh, and by the way, my other amp is an HT-5 head.

 

[USAPatriot]

Re: GO-NAD!

As I understand it, the JCA22H incorporates the JCA20H crunch channel along with the SLO preamp as a second channel. It then runs through a serial loop into the same power section as the JCA20H. So it adds all the stuff I want and nothing I don't. I just don't want to buy another amp that's nearly identical to mine.

Oh, and by the way, my other amp is an HT-5 head.

I would have gotten the HT-5 stack if I'd had the money, I think. How do you like it? You have the 5R?

The way I see it the only thing the 22H is missing is a reverb but there's no space for an analog verb in there and while the HT-40's reverb is pretty darned good, I really wouldn't want another digital. They can't put a tank into a head like this for $400 and not without making it quite a bit larger. Rock, meet hard place.

Does anyone have opinions on the JCA22H's effects loop? I looked at the 100's schematics and liked the tube based loop setup, which this one will have. Better than a PCB based loop? -Rod-

 

[misterwhizzy]

Re: GO-NAD!

No, both these amps are from several years ago, and the HT-5 is a non-reverb model. It's kind of hard to compare the two amps, honestly, although the amount of gain on top from the HT-5 is pretty incredible when you plug back into it from the JCA20. The two biggest differences are the thump from the 20 watter and the openness as well. The volume isn't drastically different, and the HT-5 is much, much more versatile.

The JCA20H is a one-trick pony, but I like its one trick better than anything I get out of the HT-5 with my Les Paul. The HT-5 plays a lot better with my PRS, but when I want a big, thick, crunchy sound, I plug the Les Paul into the JCA.

 

[USAPatriot]

Re: GO-NAD!

No, both these amps are from several years ago, and the HT-5 is a non-reverb model. It's kind of hard to compare the two amps, honestly, although the amount of gain on top from the HT-5 is pretty incredible when you plug back into it from the JCA20. The two biggest differences are the thump from the 20 watter and the openness as well. The volume isn't drastically different, and the HT-5 is much, much more versatile.

The JCA20H is a one-trick pony, but I like its one trick better than anything I get out of the HT-5 with my Les Paul. The HT-5 plays a lot better with my PRS, but when I want a big, thick, crunchy sound, I plug the Les Paul into the JCA.

The HT-40 can be that way too, limited somewhat even with two channels, but that's where the GT-10 comes in. I often run 3 delays...1 subdelay each in FX1 and FX2 plus the main delay. Each one is set differently though not drastically so and none are used as "time" effects so much as body enhancers. It's subtle but it makes a real difference. The main complaint people have about the GT-10 is the cocked wah, but I actually like it, have tried to enhance it to get that "Spirit in the sky" honk but haven't gotten there yet. Close sometimes, but no cigar. I really want to see how the GT-10 matches up with a Soldano-built amp. I've gotten pretty much what I want from the HT-40/GT-10 combo (had actually ordered the GT-100 but it looks like that's being delayed so went with the amp instead) so am hoping this will open up some more avenues for me. I like the Eminence speakers, what little I got to use them with the JCA20, and will probably test drive them on the HT-40 tomorrow. That could be fun! Sorry you didn't get the reverb on your head. Life just isn't the same without it. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

That's where the Hall of Fame comes into play. You're right, though, that life isn't the same without it. I'm actually a very recent convert to that effect, because I have owned two amps with reverb, one spring, and one digital, and they were both completely unusable. The Hall of Fame pedal actually does everything I'd ever heard in my head as far as reverb.

 

[USAPatriot]

Re: GO-NAD!

That's where the Hall of Fame comes into play. You're right, though, that life isn't the same without it. I'm actually a very recent convert to that effect, because I have owned two amps with reverb, one spring, and one digital, and they were both completely unusable. The Hall of Fame pedal actually does everything I'd ever heard in my head as far as reverb.

I've never used the Hall of Fame. What do you find special about it versus others? When you've got nothing better on your plate or bored with the day's practice, turn your reverb all the way up and have some fun with it. All the lows and mids get wiped out, most of the highs and a lot of the gain too. Hit some chords, play some riffs...what I find is that I start going places I normally wouldn't because I was locked in by the tone of the patch or preamp. You can do anything with just reverb. A lot of my rhythms were born that way, stuff I wouldn't have tried because the patch or the gain on the amp would have disallowed it. You could do that with just cleans but reverb is just a lot more interesting. When you hit on something new and cool, start tweaking it, reducing the reverb a little bit at a time and adding other stuff. Make small changes, not big ones, so your brain adjusts to and accepts the new tone.

Update and this is too cool: AMS ok'd the swap of the JCA20H for the JCA22H (the 20 is already on it's way back to AMS) and I'll pay about what I figured for the difference between the two. But what's cool is that the JCA22H is arriving tomorrow! Not only did they ship Fedex overnight but Saturday delivery too! Free. When I first ordered the 20, they quoted me $180 for that same service, which I refused. Saturday delivery alone pays for the price difference between the 20H and 22H, or it pays for a retube...My jaw woulda hit the floor when he said it was coming tomorrow...if I had one :bling:

Today I'm going to try the 2 Eminence cabs with the HT-40. If it works out well, I could definitely see taking the chassis from the HT-40 and making a head cab for it. -Rod-

 

[USAPatriot]

Re: GO-NAD!

The JCA22H showed up today! And of course, Ginger got to enjoy it before I did, howling her approval:

 

[eschoendorff]

Re: GO-NAD!

Here's the second best thing you can do for that amp.



The best thing is, as Kam said, go for a full tube swap, and use a 12AU7 as a PI. Trust me.

I really dig the Greg Howe track in the background.

 

[USAPatriot]

Re: GO-NAD!

Someone goofed up and left a sharp burr on the solder inside the footswitch's plug, which eroded through the plastic sleeve and was shorting the switch out. I couldn't switch channels and at first thought it was another amp problem. I found the burr, filed it off and reassembled and everything's working great! The crunch channel doesn't have a lot and turning it up past about 5 really isn't worth the trouble with the master turned up. It's a balancing act between crunch and master...if the former goes up the latter seems to have to come down to keep the gainy-hum in check. It sounded very good, with nice clarity so long as I balance the extraneous noise out. So far I've left the EQ at 12 o'clock due to the technical problem that I had to fix, but am well satisfied. Before I fixed the plug I did get the OD to kick in and gave it a few minutes work out. Some people have complained that the JCA22H didn't have enough oomph, and maybe that's true if playing metal but for my purposes the OD has more than enough. I haven't pushed the volume yet, will do so after I get the footswitch back upstairs. I picked up a new pair of cables so I won't have to swap them out of the two different amps but next session I also need to try out the FX loop. It should be interesting to see how the 22H's 3 extra tubes handle my GT-10. For the most part my HT-40 doesn't handle the GT-10's preamps very well though it manages the FX without problems. I looked at the JCA100H's 3 tube effects loop, assume it is the same in the 22H, and it's a very simple and sensible design. It'd be cool if it made the GT-10's preamps usable. As far as I can tell, the only thing this amp is missing is a reverb. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

I think you've misinterpreted something or miscommunicated something. Here it says the JCA22H has five preamp tubes. (One of these obviously is the phase inverter, which is arguably part of the power section.) The JCA20H has three preamp tubes, only two of which are used for gain and drive.

In the JCA22H (if I understand it right), you get the bonus of an effects loop, and that takes one of the tubes. One side to drive the loop, and one side to recover from it. The other preamp tube does in fact kick in with the overdrive channel. There's talk online of a cold clipping stage in the SLO preamp, but to be perfectly honest, I don't know what that means. But you're only really adding one tube to the gain structure. It's plenty of gain, but it's only one tube.

 

[USAPatriot]

Re: GO-NAD!

I think you've misinterpreted something or miscommunicated something. Here it says the JCA22H has five preamp tubes. (One of these obviously is the phase inverter, which is arguably part of the power section.) The JCA20H has three preamp tubes, only two of which are used for gain and drive.

In the JCA22H (if I understand it right), you get the bonus of an effects loop, and that takes one of the tubes. One side to drive the loop, and one side to recover from it. The other preamp tube does in fact kick in with the overdrive channel. There's talk online of a cold clipping stage in the SLO preamp, but to be perfectly honest, I don't know what that means. But you're only really adding one tube to the gain structure. It's plenty of gain, but it's only one tube.

I'll have to see if I can find a schematic for the 22H, one each for circuits and components. On the 100H 3 tubes are used exclusively for the loop. I assumed (wrongly possibly) that it was the same case here as the specs for the amp says it's got a tube buffered loop. Since wattage isn't an issue in the loop that I know of, I'm not sure why one would need 3 while the other not, but I'm not an amp designer Will check it out and see what I can find out. Regardless of the number, I hope it's usable for more than just modulations and other FX. If you go headphones out, some of the GT-10's preamps are very good. It's just that they don't generally play well with amplifiers. -Rod-

 

[misterwhizzy]

Re: GO-NAD!

I found a schematic of the JCA50H. The only difference between that and the 100H is the two extra power tubes (and associated supporting cast). The preamp is the same, and, as you can see there, V4 is providing the tube buffering of the effects loop. It certainly does not take three preamp tubes.

 

[USAPatriot]

Re: GO-NAD!

I think you've misinterpreted something or miscommunicated something. Here it says the JCA22H has five preamp tubes. (One of these obviously is the phase inverter, which is arguably part of the power section.) The JCA20H has three preamp tubes, only two of which are used for gain and drive.

In the JCA22H (if I understand it right), you get the bonus of an effects loop, and that takes one of the tubes. One side to drive the loop, and one side to recover from it. The other preamp tube does in fact kick in with the overdrive channel. There's talk online of a cold clipping stage in the SLO preamp, but to be perfectly honest, I don't know what that means. But you're only really adding one tube to the gain structure. It's plenty of gain, but it's only one tube.

I'll have to see if I can find a schematic for the 22H, onle each for circuits and components. On the 100H 3 tubes are used exclusively for the loop. I assumed (wrongly possibly) that it was the same case here as the specs for the amp says it's got a tube buffered loop. Since wattage isn't an issue in the loop that I know of, I'm not sure why one would need 3 while the other not, but I'm not an amp designer Will check it out and see what I can find out. Regardless of the number, I hope it's usable for more than just modulations and other FX. If you go headphones out, some of the GT-10's preamps are very good. It's just that they don't generally play well with amplifiers. -Rod-

 

[USAPatriot]

Re: GO-NAD!

I found a schematic of the JCA50H. The only difference between that and the 100H is the two extra power tubes (and associated supporting cast). The preamp is the same, and, as you can see there, V4 is providing the tube buffering of the effects loop. It certainly does not take three preamp tubes.

Was the other half of the schematics there? This one shows the components rather than a layout of the circuits. The set I saw had both with the loop isolated in reference to the Send and Return. It was very good work. It seems to me that I was actually looking for a photo of Mr. Science when I found the set, so I should be able to find it again -Rod-