How to combine the Matchess and Vox amps in a small package? Chandler Amplification.

Click Here for Chandler Amplification’s info on the CD18.

“I have been wanting to try an amp with a EF86 preamp. I studied the Vox and Matchless circuits out there and came up with an 18 watt two channel amp. The first channel has volume, bass and treble controls with a beautiful glassy clean tone with single coils. The second channel (EF86) have volume and a six position tone switch that excels with humbuckers for semi dirty and full out overdrive tones.

The power amp has a cut control and a master volume on a pull switch, so with it pushed in the MV is out of the circuit. This amp is all about driving those cathode biased EL84 into smooth overdrive, and singing feedback is possible at reasonable levels. A little bonus, when this amp was done and sitting in the living room I got to teach my twelve year old son what feedback and sustain was. “Dad how do you get the guitar to go wooow and get louder at the end?” I was so proud.

This is the first of a bunch of prototype amps I plan on building on Hammond aluminum chassis to keep in the shop to help customers hear different circuits before they make a decision on an amp. The amp was built with Weber transformers, and basic non cork sniffing parts. It took a little while to tweak to taste, but sounds great now.”
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That’s the blog of the proto, mine tosses the defeatable master volume and adds a Hi/Lo voltage switch, otherwise known as the Matchless/Vox switch. OK enough of the chitter chatter, here’s mine!

The Front:

I like keeping the cut all the way clockwise, kinda like the brightest presence. It works with both channels but yeah, I just keep it wide open. My rotary has 12 positions, I really like three of them that don’t bring huge amounts of bass. As this is the EF86 side, you gotta keep the rage in the machine under control – no easy feat! The dual 12AX7 channel has that very interactive tone stack thing going on, and you can indeed add or remove gobs of mids depending on where the bass and treble knobs are in relation to each other, pretty cool.

The Back:

You see taps for 4, 8, and 16 ohms. Both of my combo amps are 8 ohms into either the 1X10 Harvard or the 2X10 Pro Reverb, so the 8′s the way to go. Socket for the power plug, so I can swap in whatever cord I like – using a hospital grade Quail power cord for this baby. There are power and standby switches back here too.

I figured that I want to really go for more of that chimey clean and smooth roar, closer to an AC15 than an AC30, so I opted to hook the CD18 into the Harvard.

There’s a G10 Celestion Gold in there, and that Alnico is going to tell you pretty quickly how to dial in your tone. Immediately I thought “hey, this amp is maybe too Modern sounding – like a dry sheen versus a organic chime.” Yeah, none of that makes sense, right? Well it does to me, so there. Basically the response to that was Time To Tube Roll!

So I get in there and see the things I want to swap out right away – in the EF86 slot is a JJ, that’s gonegone. Instead is an Amperex Bugle Boy I had hanging around. Next is the phase inverter, a chinese 12AX7. Zai Jian to that, Hiya to the 5 star GE 5751. The power tubes are some sweet rebranded Sylvanias from a Silvertone amp, I left those alone.

Also left alone is a rebranded GE and Mullard in V1 and V2 of the 12AX7 channel. The only thing i want to swap but haven’t is the 5AR4 rectifier. I popped in a Bendix 6106 briefly since it’s the hardiest of the 5Y3 and can handle the heat, but I felt like it was cooking the EL84s too much so i stuck with the Sovtek 5AR4 for now. I’ll be on the hunt to grab something better there later.

The voltage on high, while very faithful to the Matchless approach, resulted in tone that was too clean, a bit sterile, but carried more punch. The lower voltage gets saggier and with a bit of dialing in I was able to cop those JMI-era small combo Vox tones perfectly. I found myself plugging and unplugging so much between both channels, the 12AX7 channel for the swirling 3D cleans, the EF86 channel for that uniquely Vox-like rage but with refinement and roundness in the mids.

So how come I wanted to grab something like this? Just think of it as an ode to amps long gone:

Yep, I had a monster Matchless Chieftain once, a beautiful 1X12 combo that sounded great at stage levels but kinda too much for recording. Also had a Vox AC10 Twin that honestly I had zero issues with, I just had to cash out at that point in the game. So how to get the Matchless magic and the EF86 vintage Vox thing going on? Um, in my price range? This was the answer. With the AC10 Twin, the EF86 channel was the stuff – the other was kinda too dark and had no shimmer – probably why Brian May used a treble booster on that channel, to liven it up. But with the Chandler, the 12AX7 channel has no problem bringing the sparkle, even at low levels. But the EF86 is really the winner for overdrive – it NAILS that vox grind that I remember! Again, that Matchless rotary tone idea is very well implemented here, with some nice sweet spots in it, and different sweet spots I’m sure for other guitars (and other ears).

I really feel like I have all my amp bases covered now!

Update: Now We’re Cookin’.
OK now we’re cooking. My Daystrom 5AR4 came (Mullard GZ34 rebrand), as did a copper stopper for the EF86. Unfortunately the Telefunken EF86 is just too microphonic to use, so I put the JJ EF806S back in and you know what? It’s DEAD QUIET and sounds very nice – a bit more tight than the Telefunken, but again, it gets rid of some unwanted slop too. Actually there was a tad bit of ring, but the copper stopper stopped that dead, even though the stopper didn’t fit all the way down the tube like it did for the telefunken – the JJ is just a bit wider who knew.

GE 5 Star 5751 in the phase inverter slot, the RCA 7025 in V1, the rebrand Mullard 12AX7 in V2. Fired it up and it was SOLID and brought that Vox rage in the EF86 channel, which was awesome with the high output ceramic buckers in the Explorer. the 12AX7 channel was always dead quiet and had sweet chime, and still had it after the tube roll – good stuff. can’t wait to try my ABY box with it, so i can do some channel switching on the fly, and maybe look into attenuation with the weber mass, since i hooked the chandler C18 into the pro reverb’s 4 ohm cab and it was LOUD!

Had a chance to do a quick demo after getting a Mullard EF86 in there, here you go:

Here’s a pic with the new glass – Daystrom Mullard 60s rebrand in the 5AR4 rectifier spot, matched Silvertone RCA rebranded EL84s in the power slots, the GE 5 Star 5751 in the phase inverter with a ring damper, rebrand 60s Mullard in the EF86 spot with a Copper Stopper over it and coupled to the chassis, V2 is a Mullard 12AX7, V1 is an RCA 7025.