Making the Climax sound much better

[Ron]

Today I decided to make my Kendrick Trainwreck Climax sound much better. I've owned it for several years and it hasn't resided in my main stable of playing amps because I've always thought the lead channel sounded way too shrill.

I had Ken Fischer's personal Komet 60 on loan for a week, and even owned one myself for a short time, but I had a similar issue with the tone of both amps. I tried to tame both the Komet and Climax with better tube selection, but I just didn't get these amps to where I could tolerate their brightness, which made them sound overly loud. Great for cutting through in a band, but not in my music room.

After reviewing the Francesca schematic, I decided to go ahead with some changes to my Climax to make it less shrill. At the same time, I altered the phase-inverter-to-output-tube-grid circuit, making it like the Express and some Marshall lead amps. After taste testing at various stages of the modifications, I really like both the clean and lead channels much more. I tried more mods than I kept in the end.

In case you're wondering, my Climax is the 2-10 version with 100-watt Fane AlNiCo speakers in the canarywood cabinet. I've not heard the 1-12 version.

All caps used were orange drops, except the silver micas across the volume controls and an electrolytic cathode bypass cap. Use a metal-film cathode resistor for quietness.

Here is a summary of what I did. [There is a schematic of the New Joy Zee amp available in the Trainwreck documentation section. It's in Gerald Weber's handwriting, so it should be accurate. Oddly, I have an earlier schematic dated 1997 that is identical (except for one error I found), FAXed between Gerald, Ken, and "Allen" during the final development for Climax production.]

Clean Channel Preamp

* Change the bright cap across the volume control to 100 pf.

Lead Channel Preamp

* Change the bright cap across the volume control to 100 pf. It's incorrectly noted in the New Joy Zee schematic as 5000 pf.

* In the first triode of the lead channel, change the cathode circuit bias resistor and bypass cap to 1.5k ohms and 22uf/25v respectively.

* In the output circuit of the second triode in the lead channel, connect the 0.002uf from the plate of the second triode to the input grid of the third triode. Use the two 330k resistors in parallel and connect them between the input grid and ground. You will wind up with one unused eyelet. Check the Francesca layout to better understand this simple modification.

Phase Inverter

* Change the 0.02 uf coupling cap to the phase inverter input to 0.1uf. Note that this is the cap after the 220k combining resistors from the rhythm and lead channels. Same as Francesa.

* Change the coupling caps between the phase inverter plates and the output tube grids from 0.1uf to 0.022uf. Same as Francesca and some Marshall lead amps.

Tube Selection

Selecting good tubes seems to be a way of life for Fischer-designed amps. I think that's a good thing because we are getting more of the sound of the tube and less from tone shaping networks.

I use 12AX7s throughout, except for V2, the reverb driver. You can use a 12AT7 in the phase inverter to reduce overall gain, and a 12AY7 in V1 to make the rhythm channel more vintage sounding. This amp does not like even slightly microphonic tubes, so work at finding some rugged valves. I use EL34s in the output stage and the mods were tested with them. 6L6 tubes will have more bass.

Results

I was concerned mainly about how the rhythm channel would sound with the smaller coupling caps after the phase inverter, and any imbalance in the gain between the two channels. Surprisingly, the clean channel sounded even better, IMO, than before the changes. I used a Rossington LP, Anderson Classic T (Tele), Santana I, and a Tyler HD Elite (Strat) for these tests.

The lead channel is really nice now. The shrillness seems gone (or maybe I've just lost my hearing) and the gain is not "semi out-of-control", requiring the volume control to be within easy reach. There is still lots of gain, but I don't have to crank the volume to get a "growl" now (I'm sure this was detrimental to my hearing).

If you don't like the sound, you can very easily return the circuit to its original configuration. If you have been bothered by the excessive brightness of the lead channel of the Climax, I know you will be pleased with the results, which you can do within an hour.

Next day: I just spent a couple hours playing my Climax and am I a happy boy with its new sounds. I am very surprised at how much better the clean channel sounds as a bonus. The lead channel can bark and growl at a low volume level and loves humbuckers and single-coil PUs.

I would be happy to answer questions if anyone else would like to modify their Climax in the same way.

PS (10/5/2006) I changed all twelve original 715-type Orange Drop caps on the parts board to PS-type (polyester-foil) Orange Drops. There is substantially less harshness in the sound, and the amp gain seems more controlled. It sounds very much like my Express clone, which should not be surprising since it's almost exactly the same circuit (I think there may be some different filtering in the PS, as well as the addition of a master presence cut, but I haven't compared the schematics.)

Overall, this is a very worthwhile effort to undertake with your Climax to make it into a "real" Express with a Fender clean reverb channel. IMO this is how the amp should have been built.

[nek]

Can you say how KF's personal K60 was different from stock?

[Ron]

I never looked inside (out of politeness, since the amp was on loan). I am certain that it was a stock production unit since it was in CA for the Guitar Player Magazine review. It looked like a new Komet.

[Allynmey]

I have heard that Ken does very little (if anything) to the amps once he gets them from Komet. Maybe tubes. I heard this from two people who know both the Komet guys and Ken personally. Don't shoot the messanger! i was just told this by two different people.

Allyn

[nek]

No disrespect intended. This forum is all about honoring the guy and his amplifiers. I heard one cap was added. I am just trying (as are all us hobbiests/students, here) to bridge the gap between rumor and real.

[JimiB]

probably a little more filtering on that first stage of the PS

[Ron]

I don't think Ken Fischer does anything to production units. His Komet came to me with pretty standard tubes, nothing exotic (the unit should have reflected current production, not a tweaked amp for the GP review).

It would be a huge logistical expense, a physical drain on Mr. Fischer, and buyers would want to know what tubes they were getting or might request specific tubes that they thought sounded great in their friend's Komet.

AFAIK, Komets come with new and presumably tested standard tubes. One reason for changing the design of the Constellation was to be able to use readily available, non-microphonic tubes.

If you are talking about the differences between a Climax and an Express, there are a few and you can check out both schematics on this wonderful BB.

[Ron]

I changed all 12 OD caps on the Climax's board to polyester types. This is worthwhile change as it makes the Lead channel sound very close to my Express clone. See my original post for a few more details.