Soldano Hot Mod

Soldano Hot Mod Story!

I (Hicks Electronics Corp) was the original manufacturer of the HM. I was making a plug-in device for Fender amps (The Mender), when Mike Soldano and his partner Bill Sundt devised the mod. They didn't want to spend time outside of their amp building and so contacted me about producing them. Their design used a small length of brass tubing for the case (and ground connection to the amplifier), a circuit board and several caps/resistors. (By the way, the schematic at Schematic Heaven is incorrect about some of the parts values)
I tested the mod in my Marshall amp, and it performed beautifully. We came to an agreement and I started production. So were were set to go.
I had the machined brass cases made, bought circuit boards, etc, then manufactured and sold a few to music stores, before trouble raised it's head. We had a large order (100 pieces) that shipped to Japan. The distributor alerted us that the mods wouldn't fit all the amps they were tried in. The brass tubing had no "give", and the tube bases on the Marshall amps varied in size enough that the Mod wouldn't fit some/most Marshalls.
So, I COMPLETELY redesigned the HM. I used some pieces that were originally intended for the Mender, produced a new circuit board, and replaced the type/size of the required tube sockets/pins, ground lug etc.
Unfortunately, the original product's bad rap had spread, and the reissueed piece never sold much, although it worked flawlessly.
A few years thereafter, I elected to close my shop/production, stored all my gear, and ventured into a new line of work.
Several years later I got a call about selling a piece, declined to build just one, but eventually sold all the parts to a guy in Arkansas. He wasn't able to do much either, until he saw the HMs raising some interest on Ebay about a year ago. He engaged me to build some for him using a combination of the old stock he had, and new parts I out-sourced, and has had some success almost twenty years later.
What goes around, comes around.

David Hicks

I plugged it into the middle preamp tube socket of my Marshall JCM 800 2204. Basically, this thing just reconfigures that socket to run off of a 6K11 preamp tube instead of a 12ax7 or Ecc83 type. A 6K11 is a Triple Triode, whereas a 12ax7/Ecc83 type is a Dual Triode. The result..An extra gain stage dedicated for extra preamp saturation/distortion.

I'll give it a 10 in this area because it isn't rocket science.

It does mess the EQ of the amp a little bit, but it isn't drastic. I'm running real GE 6ca7's in the power section of my JCM 800, so I can turn the gain up fairly high and still get a nice clear, distorted tone. It sounds pretty good with EL34's too. I liked it with a pair of JJ EL34's that I have. SED EL34's didn't sound all that great with it and the Ruby EL34B-STR wasn't really what I was looking for either. The GE's destroy all of those tubes for what I want to do.

It adds a LOT more gain to the JCM 800. I don't really think it's too noisey or anything. It's just typical noise associted with an extra gain stage. Mike Soldano did a nice job designing this thing. I'll give it a 9 in this area. It's not perfect, but it gets the job done.

Well, all of the circuitry is sitting inside some epoxy-like substance, so it would be kind of hard to screw any of that up in there. The 6K11's are what you have to worry about. Since they were made by either GE or Sylvania, you probably don't have to worry about them flaking out anytime soon.

If the 6K11 has a side getter, it was made by GE. Some of these are labeled RCA, Tung Sol, etc.. If it has a top getter, it's a Sylvania.

Never have had to use them, but I'm sure there isn't much they can offer in the way of support since they don't make these things any longer.

It does what it's supposed to do and that is add more gain. It will get you up there in the Hard Rock/Metal area. It's real nice.

I bought this used off of eBay and no instructions other than from what the seller told me, replace the center 12AX7 pre-amp tube in my JCM 800 2203.

I put this in the amp and fired it up. I went straight guitar>>>cable>>>Amp, took it out of standby and hot damn...this really added gain. The JCM 800 2203 is a killer amp to begin with but does not really have a lot gain. I usually use a SD-1 in the front of it. Any way with this Hot Mod, I couldn't believe how much gain I had and I didn't even dime the pre-amp. I kept looking at my pedal board to see if I had on my SD-1 but I didn't even have it powered on. The tone was not affected too much, made some minor EQ adjustments using the amps controls. I keep the pre-amp at between 6 and 8, cranked it has way too much gain and sounds a bit mushy compression wise with it dimed. It is a warm overdrive and responsive to pick attach and really sounds nice with the guitar volume backed down. You can go from so-so clean to mean with the guitars volume knob.

I play primarily hard rock and metal, some blues, jazz and fusion. This sukka really is well worth what I paid for it

Soldano Hot Mod

This device is a 12AX7 tube replacement that hot mods your favorite single channel amp. Features, there isn't any, its a tube. It about doubles the amount of gain and distortion of the amp.

I put this review in the amp section, although it isnt an amp it really isn't an effect, its a amp Mod.

N/A

I emailed Soldano asking about any specifics of this device as I had no instructions and didn't want to damage a vintage Marshall head. I got no reply from them, not surprised either. Why reply to a question on a $150 discontinued item.

I love this thing, its so cool going into an amp that I had since 84 or 85 and not having to use a OD or DS pedal in front of it. This mo is like having a tube screamer built in the amp. The great thing about is I these types of mods are reversible, all I have to do is re-install a 12AX7 in its place and you back to stock in a few seconds. This Marshall head is a beast but I don't want to permanently mod with VooDoo or Splawn Mods. I have THD Yellow Jackets (see my review of those) in it so with this Hot Mod along with THD and 20 of EL-84's it is a whole new animal and actually usable at lower bedroom volumes. Almost like I have a bew amp but yet still retain the classic JCM 800 tone.

I used several different guitars with DiMarzios and Duncans, JB Super Distortion, Screamin Demon etc and the Hot Mod sounds good with them all.

This device is no longer made by Soldano because it doesn't work in every amp, it isn't meant to be used in dual channel amps and has to be in a certain pre-amp stage. I guess htere was a lot of people too lazy to read the instructions. I heard that these were costly to make too. Soldano said that the GTO pedal is a replacement which is an OD pedal that has 2 12AX7 tubes and runs on the plate voltage of amps. I can't comment on that as I never played one :)

If you can find one of these NOC some where and know what to do with it I would not hesitate to get one. It really made an already killer amp even better in my case.

Since there are many folks in forums interest in the Soldano Hotmod, I thought I should write a review about it. I don't know how to classify it, so I'll just leave it on the effect section since it works more like a distortion effect.
Soldano Hotmod is basically a 6C10 compactron tube with an adaptor. 6C10 tubes were used as TV or radio amplifying tubes. It's a triple triode (like 12ax7 with 3 plates instead of 2) tube that has 10 times more ? or "gain" than regular 12ax7 and different pin arrangement. Replace your regular 12ax7 in V2 (2nd preamp tube) with Hotmod then you get lots of extra gain.
It really can't get any easier to use. Just pull the V2 tube out and plug Hotmod in and you are ready to go. However you might need to change the your amp setting to accommodate the Hotmod (see Sound Quality).
The time people have problems with Hotmod are when it's used in muti-channel amps. HOTMOD ONLY WORKS IN SINGLE CHANNEL ALL TUBE AMPS! Since most muti-channel amps utilize different side of twin triodes in different channel, triple triode Hotmod can't be shared and used by different channels. However, according to Mike Soldano it won't cause any damage on muti-channel amps; it just won't work. Some people might have problems with Hotmod in non-master volume amps (ex. some old Marshalls) being too loud.
If you know how to replace tubes and you have a single channel amp with master volume knob, you should have no problems using the Hotmod.

I use the Hotmod in my Soldano Atomic 16 112 combo with Parker Fly DLX.
Atomic 16 is based on SLO's crunch channel with EL84s in power amp. It has way enough gain for blues & rock without Hotmod and very versatile that way. However, even with the gain knob max out it still sounds more like smooth overdrive without enough rough grinds to get into the metal zone.
My very first impression with Hotmod is that it adds a lot more compression to my amp rather than distortion and therefore the amp's sustain become way much longer! Now I can really make every single pinch harmonic sounds like screaming, I love it! It does add lots gain to my amp. I can turn the gain knob little over "4" to get the max out gain ("11") before mod. It doesn't add much noise to my amp (the Soldano Atomic is really quiet compare to my previous Mesa) and I'm really appreciate that. It also adds lots of grinds, balls and punches to the sound. I was surprised by how much more bottom end I can get from Hotmod. With the extra sustain and bottom end bass I can get a high-gain Mesa Boogie kind sound out of my little 16w Soldano.
The best thing about Hotmod is that unlike distortion pedals, it's a tube and therefore it sounds all tube! It doesn't change the characters of your favorite amp as much as a pedal, so you can concentrate on amp setting instead of messing with both amp and pedal to get a right tone. However due to the increasing gain, sustain and bass, you do have to tweak your amp setting more wisely. A little increase in gain knob before could mean a lot difference with Hotmod in the amp.
The worst thing about Hotmod? It kills amps' clean head room! It cuts down my amp?s head room almost by half and that means a lot for a little 16w amp with one channel like mine. In my amp the clean sound starts to breakup after gain knob passed 2.5/11. But ha, if you are looking for a sparking clean sound, you should go get a 12at7 or some other lower gain tubes instead of Hotmod anyway, right?
I can still clean off the sound by rolling my guitar's volume knob half way down, but I think it has more to do with the guitar than amp (Parker Fly DLX has rather low-gain pickups compare to most SD or EMG).
By the way, out of curiosity I tried to run the Hotmod in V1 position instead of V2. I though it might add way too much gain and create some insane noise, but turned out not. The volume of the amp became really low and the string sensitivity and the dynamic became terrible! I guess there is a reason 6C10 tube is not popular in the audio field. However when it's in V2 I don't feel much lose of dynamic... well usually there is not much dynamic to speak of when play heavy and dirty anyway.
The sound definitely will vary in different amps. I'll give it an 8 because It does what it was made to do- add more gain to the amp without killing the original sound, but it does kill a little bit too much clean head room in my already humbled 16w amp. I will only use it as a secret weapon and won't consider keeping it in my amp all the time.

The adaptor is solid and I can't see what can go wrong. Most of these were made almost ten years ago and many still flooding around on eBay, so I guess it?s proved to be quite reliable.
It has a tube, and tubes do burn out over time. Therefore, I'll definitely carry an extra tube for backup.
Haven't burned out any tubes or have any problems yet. My suggestion is get a good NOS tube and it should last a real long time.

Soldano no longer makes this thing anymore.
However, I?ve tried to contact them about my Atomic 16 three times and they are very helpful. One time I even got to talk to Mike Soldano himself! I didn't notice it was him till the end of conversation and he was super friendly! I called Mesa Boogie many times too but still never get to talk to Randall Smith...

The 6C10 tubes could be hard to find. NOS 6C10 tubes don't cost as much as NOS 12ax7s(goes around $15 for one NOS GE or RCA), but I found the demands of NOS 6C10 tubes on eBay are rather high probably because it's also being used on Fender/Rivera Super champs and some old Ampeg amps.
In the future I'd like to try 6AC10 on mine since it has about 40% less gain than 6C10 and might add some more headroom. And I'm also looking for 6K11 or 6Q11 to try out since I heard they are similar to 6C10 and could be easier to find.
I think it would be fun to have Hotmod in the rig as a secret weapon and see people wondering how you get that much gain out of an old Marshall Plexi. But since it only works in single channel amp there is definitely a need for two amps in gig to get more versatile sound. For me, it would be perfect to have the Hotmod in my Soldano Atomic and A/B it with a Vox AC15 for clean.
Hotmod can defiantly turn any single channel amp into a high-gain monster, but you won't be able to turn it off on cue like a pedal. You can get a pretty decent distortion pedal for $150, but they can never retain the amp's characters and signature sound like a Hotmod.
To my knowledge, there is no other product in the market similar to Hotmod, and for what it's designed to do, I'll give it a 10.