Amplifier Review Is Up: Marshall Origin 20 Combo

[Bob Womack]

Good Monday morning to you!!! I'm about to delve into my second cup of coffee here at the studio. Last month, after a bit of research and hands-on trial, I took delivery of a Marshall Origin 20 Combo amplifier. I've spent the intervening month getting over the honeymoon phase and putting the amp through its paces with different guitars, speakers, and processing gear. You can find my review of the amp HERE.

Bob

[ChrisN]

For any unfamiliar with Bob's reviews of his gear, prepare to spend some time with the beverage of your choice, and know going in that no unanswered questions will remain by the end. I'm not in the market for any amp just now, but I'll check the review just for the educational value. Thanks, Bob.

[Bob Womack]

Originally Posted by ChrisN

For any unfamiliar with Bob's reviews of his gear, prepare to spend some time with the beverage of your choice, and know going in that no unanswered questions will remain by the end. I'm not in the market for any amp just now, but I'll check the review just for the educational value. Thanks, Bob.

Thank you for your kind words! I do try to get past that "Here's my new thing!" sort of review so it is worth the read.

Bob

[seannx]

Great review!!!

[ChrisN]

Bob, fyi, 1 typo (reaar panel), and a question.

I'm frequently confused by the difference between audio and linear pots. You say Fender uses "linear" pots to pop the volume early on, but it was my perhaps mistaken understanding that when you introduce any curve into a pot, whether to taper in, or out, of a range, then that pot is an "audio" taper. I saw linear as a straight/progressive/uninterrupted line, while audio taper is supposed to be "more like we hear" where most of the frequencies come in at some specific point in time. I may be explaining this all wrong, btw.

For example, I have a Gibson 339 - the volume pots work as I expect - close to closed = very quiet/silent, and a gradual volume increase as I turn the dial to max. I consider these pots to have be "linear" volume pots. I like them.

I also have a Gibson 390 (339-sized 330 w/mini HBs). Its volume pots function completely opposite to the 339's - there is no sound at all from the amp from "1" until "7" on the dial, then it comes all-in between 8-8.5 and 10. I do not like this. I understood these pots to be "audio" taper with a particular taper that focuses their "all-in" much later on the dial, so that those who want to control amp gain/volume via the guitar can do so with a minor turn of the knob, rather than having almost a full-turn to make that change.

Any thought on this issue appreciated.

Separately, of course I'm now interested in the Origin 20 even though I have too many amps - great review and drill-down, as always.

[Glennwillow]

Hi Bob,

Well, I went through a couple of cups of coffee while reading through your excellent review on your website. Very well done review.

I also took the time to watch the video embedded in your video and also the video embedded on Sweetwater's website. The amp really sounds good, very Rolling Stonish to my ears. Both videos were excellent.

I'm glad you are happy with this amp and its sound.

I know you have a Line 6 Helix, and I'm wondering, can you get a similar sound from the Helix? Or if not, can you tell us what you feel is different?

Thanks for all your information here, Bob. I enjoyed my morning with you.

- Glenn

[Bob Womack]

Originally Posted by ChrisN

Bob, fyi, 1 typo (reaar panel), and a question.

Thanks. I added that at the last minute and obviously didn't triple-check it.

I'm frequently confused by the difference between audio and linear pots. You say Fender uses "linear" pots to pop the volume early on, but it was my perhaps mistaken understanding that when you introduce any curve into a pot, whether to taper in, or out, of a range, then that pot is an "audio" taper. I saw linear as a straight/progressive/uninterrupted line, while audio taper is supposed to be "more like we hear" where most of the frequencies come in at some specific point in time. I may be explaining this all wrong, btw.

For example, I have a Gibson 339 - the volume pots work as I expect - close to closed = very quiet/silent, and a gradual volume increase as I turn the dial to max. I consider these pots to have be "linear" volume pots. I like them.

I also have a Gibson 390 (339-sized 330 w/mini HBs). Its volume pots function completely opposite to the 339's - there is no sound at all from the amp from "1" until "7" on the dial, then it comes all-in between 8-8.5 and 10. I do not like this. I understood these pots to be "audio" taper with a particular taper that focuses their "all-in" much later on the dial, so that those who want to control amp gain/volume via the guitar can do so with a minor turn of the knob, rather than having almost a full-turn to make that change.

Any thought on this issue appreciated.

Separately, of course I'm now interested in the Origin 20 even though I have too many amps - great review and drill-down, as always.

Audio volume is logarithmic. For something to sound twice as loud it must actually be ten times as loud. As a result, in audio circuits, audio volume is controlled by log tapered pots popularly called "Audio Taper Pots." The result is a smooth fading up of the sound through the travel of the pot. Linear tapered pots are just that - the voltage rises linearly as you rotate the pot. The result in an audio circuit is low level, low level, low level, and then a sudden jump in level to near full.

Now, it is possible to affect the apparent taper of the pot via changes in components before or after the pot. It is also possible to use different resistance pots on a guitar. My modern ES-335 has 500 ohm pots and fades off smoothly without loosing much high end. My old Les Paul has 300 ohm pots and turns dark around 8 out of 10 on the scale.

But the main point is that for an audio pot to sound linear it must be electrically non-linear, it needs an electrically logarithmic taper.

Bob

[ChrisN]

Originally Posted by Bob Womack

Thanks. I added that at the last minute and obviously didn't triple-check it.Audio volume is logarithmic. For something to sound twice as loud it must actually be ten times as loud. As a result, in audio circuits, audio volume is controlled by log tapered pots popularly called "Audio Taper Pots." The result is a smooth fading up of the sound through the travel of the pot. Linear tapered pots are just that - the voltage rises linearly as you rotate the pot. The result in an audio circuit is low level, low level, low level, and then a sudden jump in level to near full.

Now, it is possible to affect the apparent taper of the pot via changes in components before or after the pot. It is also possible to use different resistance pots on a guitar. My modern ES-335 has 500 ohm pots and fades off smoothly without loosing much high end. My old Les Paul has 300 ohm pots and turns dark around 8 out of 10 on the scale.

But the main point is that for an audio pot to sound linear it must be electrically non-linear, it needs an electrically logarithmic taper.

Bob

So, I have "audio" and "linear" backwards, it seems. The 339 must have "audio" taper volume pots, while the 390 has "linear."

Separate/related issue - my 390 brings in the volume toward the end of sweep, while you mentioned that Fender's linear amp pots bring the volume in hard near the front of the sweep to make the amp seem like it's got more on tap later. Are those two examples of two linear pots with different "tapers"?

I'm keen on this issue because I'm thinking of replacing the 390s volume pots and only want to do that job once! Thanks Bob

[Bob Womack]

Originally Posted by Glennwillow

Hi Bob,

Well, I went through a couple of cups of coffee while reading through your excellent review on your website. Very well done review.

I also took the time to watch the video embedded in your video and also the video embedded on Sweetwater's website. The amp really sounds good, very Rolling Stonish to my ears. Both videos were excellent.

I'm glad you are happy with this amp and its sound.

I know you have a Line 6 Helix, and I'm wondering, can you get a similar sound from the Helix? Or if not, can you tell us what you feel is different?

Thanks for all your information here, Bob. I enjoyed my morning with you.

- Glenn

Thanks for your kind words! The Helix has several different Marshall models including the JTM45. I treat it like a synthesizer, basically: I look for a basic model that is close to a sound I need for my work and begin building a preset around it. When I was building my presets and tested the JTM45 Norm and Brit models they didn't give what I needed. For cleans, it didn't have either the chime or jangle this amp has. And it had less gain than the ones I've used in presets as well. I am fond of the Marshall 1987 50-watt amp when it is gained up and I have found that model to be more accurate. It is in one of my lead presets.

There is a certain amount of philosophy and personal expectation that a modeling engineer brings to the table when he creates his models. There are excellent models (the Fender Deluxe Reverb and the Marshall 1987 "Brit Trem", for instance) and less than perfect ones (to my tastes). The JTM45 isn't a model I particularly prefer.

Does that help?

Bob

[Bob Womack]

Originally Posted by ChrisN

So, I have "audio" and "linear" backwards, it seems. The 339 must have "audio" taper volume pots, while the 390 has "linear."

Separate/related issue - my 390 brings in the volume toward the end of sweep, while you mentioned that Fender's linear amp pots bring the volume in hard near the front of the sweep to make the amp seem like it's got more on tap later. Are those two examples of two linear pots with different "tapers"?

I'm keen on this issue because I'm thinking of replacing the 390s volume pots and only want to do that job once! Thanks Bob

It could also be the difference between the pickups at one end and the tone pots at the other.

Bob

[Glennwillow]

Originally Posted by Bob Womack

Thanks for your kind words! The Helix has several different Marshall models including the JTM45. I treat it like a synthesizer, basically: I look for a basic model that is close to a sound I need for my work and begin building a preset around it. When I was building my presets and tested the JTM45 Norm and Brit models they didn't give what I needed. For cleans, it didn't have either the chime or jangle this amp has. And it had less gain than the ones I've used in presets as well. I am fond of the Marshall 1987 50-watt amp when it is gained up and I have found that model to be more accurate. It is in one of my lead presets.

There is a certain amount of philosophy and personal expectation that a modeling engineer brings to the table when he creates his models. There are excellent models (the Fender Deluxe Reverb and the Marshall 1987 "Brit Trem", for instance) and less than perfect ones (to my tastes). The JTM45 isn't a model I particularly prefer.

Does that help?

Bob

Yes, that is helpful, Bob.

I think as time goes by and the folks working in the modeling business get better and better, combined with more capable and faster processors, we will see physical models getting closer and closer to sounding like the real thing. It's already starting to happen on some models, as you have noted, but things take time.

In the meantime, there is nothing quite like a real amp, though they are expensive when purchased one at a time.

Thanks for your response, Bob.

- Glenn

[clintj]

To clarify one thing, Fender does not typically use linear taper pots for volume. This is a common urban legend on the Internet. Virtually all their amps from the fifties through at least the seventies use audio taper, as well as the clean channel of the Blues Deluxe and Hot Rod series amps. The Hot Rods actually use audio taper, 15% taper (one of the slowest tapers commonly available, and designated with the code A15 on schematics) for the clean channel volume and Drive channel gain. The master volume on these is linear, however. The silverface and earlier amps have less gain overall in both channels so the sound comes up more controllably.

What makes the Hot Rod amps seem so touchy is the preamp as a whole has a large amount of gain available, so small adjustments early on yield drastic changes in room volume. It's also not uncommon for some pots to have a near dead spot in the first few degrees of rotation, which accentuates this jump.

[RussL30]

Thanks for the great review, Bob.

After you mentioned it in the previous thread, this is on my shopping list. As someone with no experience, I really want to experience the tube saturated overdrive at a reasonable volume, but I wonder if it's still too much amp for home use.

I've also considered the 5, but many online complain about the small speaker. I've really liked the demos I've listened to of the origin 20 and there are some really good prices right now online.

[Bob Womack]

Originally Posted by RussL30

Thanks for the great review, Bob.

After you mentioned it in the previous thread, this is on my shopping list. As someone with no experience, I really want to experience the tube saturated overdrive at a reasonable volume, but I wonder if it's still too much amp for home use.

You could add an inexpensive Bugera PS1 attenuator ($119), pull off a few more db, and have a bedroom-level amp. But this little guy sounds right.

Bob

[Charlie Bernstein]

Good to know. Thanks!