changing classic 18 watt to 18 watt modern classic

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crgfrench
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Re: changing classic 18 watt to 18 watt modern classic

Post by crgfrench »

Bieworm wrote:
Sat 05/23/20 2:05 am
Craigh, I have the one from Josh in both my 18 watts... they just simply work. No tonal change, no signal loss.. I can't imagine wanting another type of FX loop.
That's good to hear, thanks! What specifically are you running through this FX loop and how long are the cables? i.e., "a fulldrive 2 and a wah with 6' total of cable" vs. "my entire pedalboard with overdrive, EQ, compressor, echoplex, tube screamer, fuzzface, TS808, univibe, digital delay, talkbox and a Strymon Iridium, with 36 feet of cable." My impression is that an active loop is better for the latter type setup.
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Re: changing classic 18 watt to 18 watt modern classic

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crgfrench wrote:
Sun 05/24/20 12:29 am
Bieworm wrote:
Sat 05/23/20 2:05 am
Craigh, I have the one from Josh in both my 18 watts... they just simply work. No tonal change, no signal loss.. I can't imagine wanting another type of FX loop.
That's good to hear, thanks! What specifically are you running through this FX loop and how long are the cables? i.e., "a fulldrive 2 and a wah with 6' total of cable" vs. "my entire pedalboard with overdrive, EQ, compressor, echoplex, tube screamer, fuzzface, TS808, univibe, digital delay, talkbox and a Strymon Iridium, with 36 feet of cable." My impression is that an active loop is better for the latter type setup.
I run a mad professor silver spring reverb and a boss re20 delay/ or a wampler faux tape echo. The boost pedals don't do their job right due to the location of the effects loop in the signal chain. And in front of the amp all my boosters inject too much noise... so mostly using the tmb tremolo nowadays... don't need boost pedals with that MTF*R
The delays and reverb work very nice in the loop. Well, the re20 not so.. it colors the sound too much due to the notorious built-in preamp. It roundens the sound and makes it too polite.. But the wampler's great for that matter.
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Re: changing classic 18 watt to 18 watt modern classic

Post by JMPGuitars »

#2 and #3 appear to be very similar concepts.

I'm not a big fan of the kits. Having to run heaters to a floating PCB, and/or the other connections seems like a great way to add noise to a build. Maybe they're great, I dunno. Sounds noisy in my head. ;)

The other thing I like about #1 is that it's true bypass when not in use.
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Re: changing classic 18 watt to 18 watt modern classic

Post by zaphod_phil »

Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
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Re: changing classic 18 watt to 18 watt modern classic

Post by JMPGuitars »

zaphod_phil wrote:
Sun 05/24/20 9:36 am
Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
Sure, but do you bother with modulation effects or reverb pedals? That type of stuff adds more noise if it goes through the front end. Especially a lot of the digital effects. They cause much less noise through an FX loop.
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Re: changing classic 18 watt to 18 watt modern classic

Post by Bieworm »

zaphod_phil wrote:
Sun 05/24/20 9:36 am
Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
That's not always true ZP. I found out that the noise level of digital effect pedals is being amplified too much in front of an 18 watt. In the loop it's way better ... waaaaayyyy better. That's why I have the loops in both my 18'ers. Sorry for the comparison, but none of my fender amps suffer from that noise ... both of the18 watters do
I don't mind cranking a reverb effect.. I even like that.. But there are really only A handful of verb pedals that are crankable.. I know that the EHX holy grail and the mad professor silver spring reverb sound great cranked and have very little digital traces in the cranked sound.
The real deal pedals OTOH are really disgusting when cranked. The boss 63 reverb, the flint, topanga... absolutely fabulous pedals played clean are a real digital nightmare when pushed in OD
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Re: changing classic 18 watt to 18 watt modern classic

Post by crgfrench »

zaphod_phil wrote:
Sun 05/24/20 9:36 am
Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
Phil, what FX do you typically use straight in to the front end?
Jimi used to run a Vox Wah, RM Octavia, Arbiter Fuzzface (later RM Axis Fuzz), and a Univibe straight into the front end of his plexis.
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Re: changing classic 18 watt to 18 watt modern classic

Post by zaphod_phil »

zaphod_phil wrote:
Sun 05/24/20 9:36 am
Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
Bieworm wrote:
Sun 05/24/20 11:53 am
That's not always true ZP. I found out that the noise level of digital effect pedals is being amplified too much in front of an 18 watt. In the loop it's way better ... waaaaayyyy better. That's why I have the loops in both my 18'ers. Sorry for the comparison, but none of my fender amps suffer from that noise ... both of the18 watters do
I know the theory but I tend to think that it gets somewhat over-exaggerated, as the classic 18W doesn't have much real signal gain.
And what's the use of feeding weak-sounding preamp distortion into your FX boxes? :roll: And keep in mind that if you add an FX loop, you no longer have a true Marshall 18W, but some kind of a hybrid Frankenamp.
If you want it to sound good, then probably the best approach would be to tap some signal off of the speaker/OT connection and feed that into your FX chain.
crgfrench wrote:
Sun 05/24/20 12:10 pm
Phil, what FX do you typically use straight in to the front end?
Jimi used to run a Vox Wah, RM Octavia, Arbiter Fuzzface (later RM Axis Fuzz), and a Univibe straight into the front end of his plexis.
Good question ! :) Wish I was like Jimi :( :lol:
I try to keep it fairly simple, because I want to mainly have the sound of the guitar and amp coming through, with just a little FX flavour added. :)

So I use my own tweaked version of a Range Master, a Boss CE-2 chorus (original "analog" version), a Boss DM-2 analog delay and a JMP wah (made by our very own Josh).
They sound good when playing live, and i don't find any significant noise problems. I also have a Joyo TS808 clone, but like many others around here, I don't find Tube Screamers particularly useful with 18W type amps.
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Re: changing classic 18 watt to 18 watt modern classic

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zaphod_phil wrote:
Sun 05/24/20 6:25 pm
zaphod_phil wrote:
Sun 05/24/20 9:36 am
Since an 18W amp's real distortion is created in the power stage, I really don't see the point of an FX loop. I just plug any FX straight into the input jack and it sounds great!
Bieworm wrote:
Sun 05/24/20 11:53 am
That's not always true ZP. I found out that the noise level of digital effect pedals is being amplified too much in front of an 18 watt. In the loop it's way better ... waaaaayyyy better. That's why I have the loops in both my 18'ers. Sorry for the comparison, but none of my fender amps suffer from that noise ... both of the18 watters do
I know the theory but I tend to think that it gets somewhat over-exaggerated, as the classic 18W doesn't have much real signal gain.
And what's the use of feeding weak-sounding preamp distortion into your FX boxes? :roll: And keep in mind that if you add an FX loop, you no longer have a true Marshall 18W, but some kind of a hybrid Frankenamp.
If you want it to sound good, then probably the best approach would be to tap some signal off of the speaker/OT connection and feed that into your FX chain.
crgfrench wrote:
Sun 05/24/20 12:10 pm
Phil, what FX do you typically use straight in to the front end?
Jimi used to run a Vox Wah, RM Octavia, Arbiter Fuzzface (later RM Axis Fuzz), and a Univibe straight into the front end of his plexis.
Good question ! :) Wish I was like Jimi :( :lol:
I try to keep it fairly simple, because I want to mainly have the sound of the guitar and amp coming through, with just a little FX flavour added. :)

So I use my own tweaked version of a Range Master, a Boss CE-2 chorus (original "analog" version), a Boss DM-2 analog delay and a JMP wah (made by our very own Josh).
They sound good when playing live, and i don't find any significant noise problems. I also have a Joyo TS808 clone, but like many others, Idon't find Tube Screamers particularly useful with 18W type amps.
Well the whining noise I get from putting the verb and delay on front of the preamp is nearly gone through the loop, so it Works best for me. Both my 18 watts go from quiet without to noisy with any pedal up front.
How does that work exactly... FX loop at the speaker output ?
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Re: changing classic 18 watt to 18 watt modern classic

Post by zaphod_phil »

Bieworm wrote:
Sun 05/24/20 10:38 pm
Well the whining noise I get from putting the verb and delay on front of the preamp is nearly gone through the loop
Wow, a whining noise! 8O I've never come across that myself :? I thought maybe you were just talking about some hiss. I wonder if there's a fault in either or both of the pedals. Does this whining noise just happen when you daisy-chain both pedals into the amp, or can it happen with just one of them?
Bieworm wrote:
Sun 05/24/20 10:38 pm
How does that work exactly... FX loop at the speaker output ?
Here's just my rough, quick and dirty idea. Put a 5k pot across the OT secondary connections to your speaker, with a 0.1uF cap on the wiper. That's your FX Send, with a nice full distortion sound :). Then you can carry on with the FX Return you've already been looking at, or alternatively use the other preamp channel input for your Return. Start with the FX volumes and 5k pot set to minimum and bring up the Send level, and FX volumes very, very slowly, to avoid any unwanted feedback effects. If there's any sign of feedback howl, you can swap the OT secondary connections on the 5k pot, to reverse the phase.
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Re: changing classic 18 watt to 18 watt modern classic

Post by Bieworm »

zaphod_phil wrote:
Mon 05/25/20 3:05 pm
Bieworm wrote:
Sun 05/24/20 10:38 pm
Well the whining noise I get from putting the verb and delay on front of the preamp is nearly gone through the loop
Wow, a whining noise! 8O I've never come across that myself :? I thought maybe you were just talking about some hiss. I wonder if there's a fault in either or both of the pedals. Does this whining noise just happen when you daisy-chain both pedals into the amp, or can it happen with just one of them?

--> every delay or reverb pedal I have does it. And they're ok + separately powered
Bieworm wrote:
Sun 05/24/20 10:38 pm
How does that work exactly... FX loop at the speaker output ?
Here's just my rough, quick and dirty idea. Put a 5k pot across the OT secondary connections to your speaker, with a 0.1uF cap on the wiper. That's your FX Send, with a nice full distortion sound :). Then you can carry on with the FX Return you've already been looking at, or alternatively use the other preamp channel input for your Return. Start with the FX volumes and 5k pot set to minimum and bring up the Send level, and FX volumes very, very slowly, to avoid any unwanted feedback effects. If there's any sign of feedback howl, you can swap the OT secondary connections on the 5k pot, to reverse the phase.
--> thx ZP!!! In case I ever feel the need for it I will dig deeper into that idea

ZP, is this what you mean?
FX loop ZP.pdf
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Re: changing classic 18 watt to 18 watt modern classic

Post by crgfrench »

That looks like you drew the pot across the OT primary. ZP mentioned the OT secondary.
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Re: changing classic 18 watt to 18 watt modern classic

Post by Bieworm »

crgfrench wrote:
Mon 06/01/20 9:38 am
That looks like you drew the pot across the OT primary. ZP mentioned the OT secondary.
Good catch!!! That is what I had in mind, but drew it wrong
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Re: changing classic 18 watt to 18 watt modern classic

Post by zaphod_phil »

You should probably also have a DC-blocking cap at the PI input you're using for the FX return, perhaps the usual 0.022uF.
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