Marshall JCM800 Studio Classic SC20H Review
Marshall JCM800 Studio Classic SC20H Guitar Amplifier Review
I had a chance to test out and review the 2019 Marshall JCM800 amplifier head. Firstly, I need to state I am a huge Marshall DSL40CR amplifier fan. When I had a chance to borrow the JCM800 amplifier for a review I was ecstatic.
Where is the Marshall JCM800 SC20H Made?
Amazingly, the 2019 Marshall JCM800 amplifiers are made in the UK. The majority of the Marshall amplifiers are made in Vietnam so this is a welcomed addition to the lineup.

Build Quality
Externally, the Marshall JCM800 Studio Classic SC20H is built extremely well. Marshall has used a more premium strength Tolex on the amplifier head which feels a lot tougher than what they use on the DSL amps. The grill cloth used also feels much better than the DSL amplifiers which becomes pretty saggy quickly. The grill cloth on the JCM800 Studio classic feels a lot better to the touch than whatever Marshall is using on the Vietnamese-made amplifiers.
Internally, these have mixed reviews. I never opened up the head as mine was only on loan to shoot the video review. Some people have said the internals of the Studio Classic JCM800 is “average at best”. I think a lot of people were expecting point-to-point wiring as it was made in England. The thing is, this is not cost-effective and it would have increased the price of the amplifier exponentially. Handmade English Marshalls are so expensive they are out of reach for most musicians.
First Impressions
Plugging into the Marshall JCM800 for the first time is an experience and a half. At the time of testing, this amplifier I had it running through my Marshall MX212 closed-back cabinet loaded with Celestion Seventy 80 speakers. My first thought was, “Wow this is awesome but very bright!”.
The brightness is inherent in these guitar amplifiers and it’s what makes them sound so unique and impressive. A bright sound isn’t for everyone but there’s almost nothing that will give you that “Rock n Roll” sound like a JCM800.
Is the Marshall JCM800 Studio Classic loud enough to gig with?
YES! Through my 2×12 Marshall box, it was brutally loud (in all the right ways). This is one of the loudest 20-watt heads I have ever heard. Putting it up against my Joyo 20 watt amplifiers it’s not even close volume-wise (as it shouldn’t be). If the louder volume is what you’re after, then the Marshall MX212 speaker cabinet I use is a great match for this head. Even with the Celestion Seventy 80 speakers, this is one loud combination.
Is the Marshall JCM800 amplifier worth it?
If you’re looking for the Rock and Roll sound then Yes. If you are looking for an amplifier that has more bells and whistles then no. There are no dedicated clean channels on this amplifier. You get two inputs and the lower one is cleaner than the top one but it’s not like having a dedicated clean channel.
The other thing that might be a deal-breaker is there is no built-in reverb either. I found that using a reverb pedal in the FX loop gave me a much more pleasing sound to my Ear than without it.

How does it compare with the Marshall DSL40CR?
The Marshall JCM800 and Marshall DSL amplifiers sound totally different from each other on the most part. There are “some” similarities but overall they are two different amps. The advantage of the JCM800 is those buying it will only want the rock and roll sound it delivers and nothing else. This advantage is also it’s one glaring disadvantage.
The Marshall DSL40CR I own is now loaded with an Eminence Texas Heat speaker which rounds out some of that top end and turns it into a blues-rock machine. Another advantage to the DSL40CR is you get two crunch channels, an ultra-gain channel, and a dedicated clean channel. There’s a lot more tonal variety in the DSL40CR than the JCM800 Studio Classic but the one thing the DSL can’t quite nail is that JCM800 sound.

What is the best overdrive pedal for the Marshall JCM800 Studio Classic?
In terms of effects to run into the front end of the amplifier, my favorite one was simply a volume boost pedal. I tried running a Tubescreamer into the JCM800 but it honestly sounded way better just turning the gain on the amp up over using any dirt pedals. For best results, I can highly recommend using a volume pedal to push it that little bit more. Overdrives and distortions are not required for this amplifier at all.
You “could” dial in the amp cleaner and run your favorite pedals but if you are planning on that then go for an amp that has reverb or a dedicated clean channel. You are buying the JCM800 for the rock and roll sound it produces. Using anything other than a volume boost pedal seems to subtract from what it does best.
Marshall JCM800 Amplifier Specifications
All of the 2019 Studio Classic Marshall amplifiers are loaded with two EL34 power tubes and two ECC83 preamp tubes. In terms of the main control panel, we also get a very musical 3 band EQ with an added presence control. This amplifier as mentioned is very bright my bet is you won’t be using a lot of additional presence.
The back panel of the amplifier features a plethora of speaker outputs perfect for any cabinet you have laying around. We have a choice of multiple 8 and 16ohm speaker outputs so you can run two cabinets if need be.

FX Loop Issues
One of the things I’ve seen in the comments section of my video review is the FX loop issue. While I didn’t experience this first hand I will explain the issue. If you have a pedal going through the FX loop and you turn the effect on you can hear a “pop” through the amplifier. I didn’t notice this using the Anasounds Spring Reverb pedal through the FX loop. The reverb effect I used has an on/off switch and it was fine so I think the FX loop issue might only relate to certain effects or maybe even certain amplifiers, but not all of them.
What is the matching Marshall 2×12 Speaker Cabinet Like?
Marshall also released a vertical 2×12 speaker cabinet for the JCM800 called the SC212. This speaker box is loaded with 2 x Celestion V-Type speakers. The V-Type speakers are very solid and the vertically orientated speaker cabinet looks great.
I had a chance to try their SC212 vertical cabinet and I felt like it made the amplifier even brighter to your ear because of the orientation of the cabinet. Having tested the JCM800 SC20H with the verticle cabinet and my Marshall MX212 I actually prefer the MX212. It felt much fuller and louder than the vertical cabinet while also perhaps not sounding quite as bright in the room.
Buy the Marshall JCM800 on Sweetwater
Marshall SC20H Studio Classic 20/5-watt Tube Head
Final thoughts about the Marshall JCM800 SC20H
If you’re a fan of classic rock this is the go-to amp for that one sort of sound. This also means the amplifier is a little bit one dimensional. The reason it is a little one dimensional is that what it does, it does really well and doesn’t do much else. If you’re looking for one of the ‘holy grails’ of rock and roll amplifiers then give the Marshall JCM800 SC20H a shot.
If you are looking for a higher gain amplifier check out my review of the Marshall DSL40CR guitar amplifier. The DSL40CR has it also has a channel called Ultragain that will appeal to those looking to cut loose with something a little more ‘in your face’. I spent a lot of time using the DSL40 as well as writing the review so it will help you make your mind up on which amplifier is right for you.