Newcomb E-17 17w amp advise

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Spring cleaning has suddenly brought some tube amps into my life. None of which are specifically guitar amps.

Having never had a vintage tube amp at all I began reading up on theory before I started plugged them in.

I personally primarily value function but honor peoples views on original vintage stuff and understand that there's less vintage original stuff everyday.

One of the amps is a Newcomb E-17 in great shape that came to me in original condition.

Pondering the Newcomb, the fact that it's not stereo weights heavy and I'm fine with moding it but am in no hurry.

I've seen references online to folks modding the same model into guitar amps but no real details on what they did.

So I got a variac.

Then I switched out the power cord for a 3 prong and left everything else original including the old 4 prong rectangular mic jack.

Next I soldered a line in from the enclosure side of the mic jack to a 1/4 inch jack and am currently alligator clipped out for to an 8 ohm 12 inch 100 watt speaker.

I'm new to tube amps so I can't compare it to anything other than my RCA model 400 projector. That's another subject but I'll mention that the projector came to me modded with some diodes and has nice compression that seems almost like a tube version of an Orange Squeezer but I haven't traced it yet

Anyway, the Newcomb goes from a very crisp and clean tone to a almost fuzzy distortion with the combo of the tone stack and the guitars tone pot.

Channel 1's pot with no input acts as some sort of presence.

It's the loudest amp I've ever played but that doesn't mean much.

The Newcomb doesn't go to far into tube compression territory and overall tends to have a crisp attack and be bright even when I push it. Mostly too bright for my taste.

Having just got it going yesterday I've only used it clean and with an Orange Squeezer > Angler(Sea Blue with bias pots) EQ so far.

I'm curious about using both channels simultaneously with a different pedal chain on each one.

After I post this I'll put a line in on the phono jack/channel 1 and make a ABY box. I've got a stereo to dual mono cord so I'll be able to go it both channels simultaneously.

I previously thought about putting an extra chassis under it for tremolo and reverb and also thought about replacing the tone stack with a transformer free "Poorman's EQP1-A". Like I said I'm in no hurry thought. Better to think things through and not just hack at it like it's the enclosure from my 1st pedal.

To put things in perspective, besides the Newcomb and the projector I also have a Akai model 345 reel to reel that has a 30w mono or 15w stereo amp.

I'm current thinking about converting the projector to a full on compressor, the Newcomb to an EQ and the Akai to a power amp with tape delay. Putting reverb, tremolo, and vibrato in either the Newcomb or the Akai.

What I'm curious about is what folks with amp building/moding experience would do with the Newcomb. Might as well explore options and learn more theory before doing any drastic changes.

Any and all suggestions are welcome with the caveat that I'm not going to keep it original unless somebody makes me a stupid offer. Don't be that fool, it isn't stereo.

Much thanks for any words of wisdom both past and future.

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So put patched in a 1/4 inch jack to the exisiting RCA phono input on the Newcomb and made a ABY box.

Channel 1 is pretty quiet, as it was designed to be fed a tube record player and has no preamp.

Increasing the level of Channel 1 lowers the output from Channel 2. With the guitar straight in both channels and Channel 1 maxed it has a nice fuller sound.

Next I put a Fuzz Face into Channel 1 and left Channel 2 Clean. Even with Channel 1 turned all the way down the Fuzz Face was in the circuit of course. Lots of intresting textures were to be had between the level settings while feeding the 2 channels simultaneously.

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Ok so I've been using it with the Orange Squeezer and Angler (Sea Blue) EQ going into Channel 2 as my "clean channel " even though it's the one with the preamp. This gets it sounding more guitar amp that hifi.

I have dirt going to a volume pedal that feeds Channel 1, which is the channel that feeds in to the tone stack after the preamp.

Depending on the dirt and how the levels are set I can use the volume pedal to overcome the clean without having a "painted on" sound. It's similar to the cleanup of a fuzz with your volume knob.

It's swell heaven.

This might be old news to most of you but I've never split my signal like this before.

Using the dirt chain with one foot on a wah and the other on the volume pedal makes my lap steel sing like nothing I've ever played.

One issue came up.

I have a silicon Fuzz Face I made and if I put at the start of Channel 1 then Channel 2 sounds like a misbiased fuzz even if the level of Channel 1 and the volume pedal are turned all the way down. This happens no matter what I put inbetween the Fuzz Face and the volume pedal.

It sounds good to my ears but it's not the "clean" channel anymore and it makes me wonder about the impedance of that input and it's effect on the self biasing of the 12AX7 as I'm using it.

It's strange to me that the other fuzzes nor my wah have a similar effect.

I'm working on putting together a multi function impedance utility box that combines a few designs from Anderton, Orman and Phatt so I can do some tests and figure out what's going on.

Something else that I haven't figured out is on the output impedance selector there's the 500 socket with the negative feedback line from the 6sj7's cathode. The closest thing to that which I've seen is the Princeton 6G2 and references to some folks removing it or putting it on a switch.

I have not delved much the into reasoning nor the OT and speaker transformer of the 6G2.

I'm curious about the general application of the 500 socket and it's possible use as a sidechain tap while also using the another tap for output.

One of the paths in the impedance utility box that I'm working on is Phatt's speaker to line converting circuit from this post.

viewtopic.php?p=259117#p259117

In the grand scheme of things I want to integrate my various amps together into a studio rack esque setup like I've previously mentioned.

I've been thinking about how to link them and started with the speaker to line approach but am wondering if I can do better than that by feeding Channel 1 with my RCA amp as a compressor in a sidechain implementation, possibly with a switch that enables feed forward to the 12AX7 as well as into the tone stack like Channel 1.

I'm so glad that I didn't just buy a standard guitar amp for my 1st tube amp. This Newcomb is a really great little unit with lots of options. The layout is spacious and elegant. It's seems a really a wonderful topology for introduction to tube amp theory with the way is varies from most push pull guitar amps yet retains the the basics.