Marshall JCM800 vs JCM2000 Series

[Gearjoneser]

Re: Marshall JCM800 vs JCM2000 Series

Difference in sound between the 100W and 50W plexi reissues is that the 100W has to be played on '2', or you'll blow the ceiling off your room! They also sound a bit deeper on the bottom. The 50W are just about as loud, only they're more appropriate for almost anyone. They're definitely not home practice rigs. They're really only good for stages and rehearsal rooms. The DSL50 is a far better choice for a home practice/gigging amp.

And, if you're a player that likes highgain, the plexis aren't really the amp for you. DSL's, TSL's, Jubilees, and the Mode 4 might be more to your liking.

[APB_4]

Re: Marshall JCM800 vs JCM2000 Series

Just checked out the THD website, have you looked at the amps? AUTOMATIC REBIASING!! How cool is that?!

[MikeS]

Re: Marshall JCM800 vs JCM2000 Series

Sorry for not getting back to you on Friday- I didn't get a chance to post until today and forgot about this thread!

No biggie, I was out of town myself.

I know you said to cover the holes- and I did misuse the term "infinite baffle." However, I'm pretty sure any size hole in a cabinet can be considered "porting." Whether it's the little 2" breather holes in the baffle, to a slot running the length or width of the cab drawn from the rear of the cab. (I had played around with the idea of replacing the baffle in my 2x12 and port it, I got a bunch of great reccomendations from a dude who works at some fancy pants cabinet manufacturer in Mass.)(No, I didn't do it- the baffle is actually built into the walls of the cab.)

Given the diameter of the openings and the depth of the ports, these are not tunable openings. The openings will likely cause some cancellation if left open since they are in the front of the cab. If you like I could calculate the frequency of the ports... but it ain't going to be pretty.

I can't think of a good, practical reason to go through the effort of yanking two speakers out of a 4x12 and plugging the holes. You're still left with a big, heavy box, with (roughly) half of your potential volume gone.

Easy... it's gar easier to replace to speakers in an existing 4x12 cab that I never move than it is to build myself a custom 2x12 cab for some drivers I have laying around. Additionally, double the speakers DOES NOT = double the volume. The volume increase between a 4x12 and a 2x12 receiving the same wattage is barely noticable.

Additionally, I did in fact try this over the weekend by removing two original speakers (leaving two in and disconnecting them), and replacing them with a pair of greenbacks. As soon as I digest the tone a little more, I'll let you know what I think.

[The Golden Boy]

Re: Marshall JCM800 vs JCM2000 Series

Given the diameter of the openings and the depth of the ports, these are not tunable openings. The openings will likely cause some cancellation if left open since they are in the front of the cab. If you like I could calculate the frequency of the ports... but it ain't going to be pretty.

Easy... it's gar easier to replace to speakers in an existing 4x12 cab that I never move than it is to build myself a custom 2x12 cab for some drivers I have laying around. Additionally, double the speakers DOES NOT = double the volume. The volume increase between a 4x12 and a 2x12 receiving the same wattage is barely noticable.

Additionally, I did in fact try this over the weekend by removing two original speakers (leaving two in and disconnecting them), and replacing them with a pair of greenbacks. As soon as I digest the tone a little more, I'll let you know what I think.

No need to go calculating the frequency of ports vs. the volume of air vs. the amount of speaker space vs. the resonant frequency of 6 layer Baltic Birch Plywood vs. insulation space vs... Regardless of a pleasant, desired effect, as with matching drivers with cabs, the openings would serve the same purpose as a port- again, not saying that that purpose would be pleasing or desirable.

With the dearth of companies that are selling affordable, quality constructed cabinets- Avatar comes immediately to mind- it's more time/cost effective to get a new cab than it is to make one. For any kind of practical application, hauling a 2x12 that takes up the space of and weighs nearly as much as a 4x12 doesn't make a lot of sense. As Fender (for one) has released full sized 2x12 cabs- they didn't prove to be terribly poplular, and still aren't terribly poplular with collectors (or tone freaks for that matter).

As far as wattage+speaker space= volume... I've found this on the web and posted it in an earlier thread:

40 watts is 94% as loud as 50 watts.
30 watts is 86% as loud as 50 watts.
25 watts is 81% as loud as 50 watts.
22 watts is 78% as loud as 50 watts.
20 watts is 76% as loud as 50 watts.
18 watts is 74% as loud as 50 watts.
15 watts is 70% as loud as 50 watts.
12 watts is 65% as loud as 50 watts.
10 watts is 62% as loud as 50 watts.
9 watts is 60% as loud as 50 watts.
8 watts is 56% as loud as 50 watts.
7 watts is 55% as loud as 50 watts.
6 watts is 53% as loud as 50 watts.
5 watts is 50% as loud as 50 watts.
4 watts is 47% as loud as 50 watts.
3 watts is 43% as loud as 50 watts.
2 watts is 38% as loud as 50 watts.
1 watt is 31% as loud as 50 watts.
3/4 watt is 28% as loud as 50 watts.
1/2 watt is 25% as loud as 50 watts.
1/4 watt is 20% as loud as 50 watts.
1/10 watt is 15% as loud as 50 watts.
50mW is 13% as loud as 50 watts
20mW is 10% as loud as 50 watts.
10mW is 8% as loud as 50 watts.
5mW is 6% as loud as 50 watts.
1mW is 4% as loud as 50 watts.
0.5mW is 3% as loud as 50 watts.
0.1mW is 2% as loud as 50 watts.
50uW is 1.6% as loud as 50 watts.
10uW is 1% as loud as 50 watts.

I'm not vouching for the scientific validity of that- however to my untrained ear it comes out about right. For years I lugged around a 100w head because I was convinced I'd need that extra volume. After realizing I got a better tone out of similar 50w heads, I A/B'd stuff and the 50 to 100w volume difference in any practical application is negligible. The figure I hear most often is a 12% difference in volume. The reason I don't like gigging with my 19w combo has more to do with issues with the tone of an open back cabinet than it does with any volume issues. I currently have 3 bass heads, 2 old 600w Seymour Duncan heads, and a 900w SWR head. The practical volume of each head is comparable, where the difference comes in is in the headroom and the usable bottom end.

Out of curiosity, what kind of cab, what kind of speakers are being replaced, and are these original Greenbacks?

[MikeS]

Re: Marshall JCM800 vs JCM2000 Series

I completely agree that it is far easier to buy a cab than to make one. I also will not argue the fact that a 2x12 is easier to move than a 4x12. I never intended to sound confrontational, but simply tried to offer some other, perhaps unorthodoxed, opinions on cabinet construction.

That wattage chart is definatly interesting... I've seen you post that before and wondered how they calculated that. Percieved volume is not the same as measured volume. But, based on what I've heard, those numbers are probably fairly accurate, all other things being equal, of course.

The cab I'm trying this on is a Fender RocPro cab (3/4" plywood construction, closed back). I'll have to look and see what model of Fender speakers I yanked out, but I did replace them with Celestion Greenbacks. Two Fender speakers remain as dummy speakers.

[Kommerzbassist]

Re: Marshall JCM800 vs JCM2000 Series

Difference in sound between the 100W and 50W plexi reissues is that the 100W has to be played on '2', or you'll blow the ceiling off your room! They also sound a bit deeper on the bottom. The 50W are just about as loud, only they're more appropriate for almost anyone. They're definitely not home practice rigs. They're really only good for stages and rehearsal rooms. The DSL50 is a far better choice for a home practice/gigging amp.

And, if you're a player that likes highgain, the plexis aren't really the amp for you. DSL's, TSL's, Jubilees, and the Mode 4 might be more to your liking.

Now.. what I don't get is why is the Plexi so loud but not a high gain amp? What defines high gain amps? And What's the difference in volume between a DSL 50 and a 1987X Plexi? Which one must be cranked up more to sound good (I mean Voulme not actually 1-10)?
Btw... how hard is the overdrive of a fully cranked 1987? Hendrix Voodoo Child style, more or less?

thanks

[tone?]

Re: Marshall JCM800 vs JCM2000 Series

my 2 cents is DO NOT BUY A MARSHALL PERIOD.

sorry im so biased but i have a JTM60 that i am trying so hard to get rid of.

wasted so much money on this sucker. one, because it cost around 1200euros and then i spent well over another grand fixing the damn thing.

i also have borrowed for a long time a JCM800. it has much better tone and is built more like a tank.

BUT, there are so many companies out there that make much better MArshalls than Marshall does.

It is my opinion that the Marshall sound we look for is either a heavily modded old marshall ( to sound more hard rock/metal) or a vintage Marshall cranked to get cool ZZtop and vintage sounds.

Now how easy is it to do both?

it seems silly to me to mod a Marshall. and they are not practical cause they just have to be cranked.


So many choices out there that do Marshall way better than themselves.

my 2 cents.

if you spend money on a dsl50 or something like that, you are gonna get not even 50% of the tone you want, they will be unreliable and you will lose alot of money later on cause for sure you will upgrade.

i figure if you are gonna buy a tube amp, why not invest in a great one that can in worse case scenario be sold later without losing too much dough.
get it right the first time around, i think.

[MikeS]

Re: Marshall JCM800 vs JCM2000 Series

i figure if you are gonna buy a tube amp, why not invest in a great one that can in worse case scenario be sold later without losing too much dough.
get it right the first time around, i think.

That sounds an awful like a "go big or go home" mentality... which is very tough to have when you are a younger player without a lot of cash flow Besides, half the fun of owning all this gear is modding it, right? I mean, that's why we're all interested in Seymour Duncan pickups, right? Or maybe we should have all bought guitars with Duncan pickups preloaded and "got it right the first time."

[The Golden Boy]

Re: Marshall JCM800 vs JCM2000 Series

I completely agree that it is far easier to buy a cab than to make one. I also will not argue the fact that a 2x12 is easier to move than a 4x12. I never intended to sound confrontational, but simply tried to offer some other, perhaps unorthodoxed, opinions on cabinet construction.

That wattage chart is definatly interesting... I've seen you post that before and wondered how they calculated that. Percieved volume is not the same as measured volume. But, based on what I've heard, those numbers are probably fairly accurate, all other things being equal, of course.

The cab I'm trying this on is a Fender RocPro cab (3/4" plywood construction, closed back). I'll have to look and see what model of Fender speakers I yanked out, but I did replace them with Celestion Greenbacks. Two Fender speakers remain as dummy speakers.

There's loads of information here, and especially with trying things that aren't commonly done- there are plenty of opinions that can go either way. I hope I'm not coming across as pushy or confrontational (I always wonder how things come across in this medium).

The thing is, most things that I've heard Greenbacks (and similar speakers) in, they sound good in most applications. Where everybody knows Greenbacks from is from sealed 4x12 cabs- but they use(d) the same speakers in the combos as well. From what I'm able to tell- for the most part is that the speakers match the head more than the speakers match the cab. Sort of like using a Jensen in a Fender and then trying it in a Marshall... From what I've heard (and I've done very little tinkering here) is that for bass enclosures, it's more important to get the driver to match the cab- as cab tuning is more of an issue with bass. Whether that's because of frequency or the sheer high power involved, or if it's one of those myths that get passed around...

Another wacky factor as far as cabs go is insulation. Something that was told to me that doesn't make sense, but I respect the professional credentials of the source, is that too much insulation can "fool" a speaker into behaving as if there's less pressure behind the speaker, rather than just taking up space or increasing the pressure behind the speaker...

[The Golden Boy]

Re: Marshall JCM800 vs JCM2000 Series

Now.. what I don't get is why is the Plexi so loud but not a high gain amp? What defines high gain amps? And What's the difference in volume between a DSL 50 and a 1987X Plexi? Which one must be cranked up more to sound good (I mean Voulme not actually 1-10)?
Btw... how hard is the overdrive of a fully cranked 1987? Hendrix Voodoo Child style, more or less?

thanks

Think of "high gain" as being the signal your preamp sends to the power section. You can have a 200w Marshall Major, anyone that's played an unmodded Pig can tell you, it's not high gain, to get it to sound "good" it's got to be ear bleedingly, cabinet blowingly loud. However, an amp that really cooks the preamp (or induces distortion in the preamp stage) would be considered high gain. Think something like a Mesa Triple Rectifier.

[MikeS]

Re: Marshall JCM800 vs JCM2000 Series

From what I'm able to tell- for the most part is that the speakers match the head more than the speakers match the cab. Sort of like using a Jensen in a Fender and then trying it in a Marshall...

Very true, IMO, matching speakers to the head is far more important than mathcing speakers to teh cab (for guitar loud speakers that is).

From what I've heard (and I've done very little tinkering here) is that for bass enclosures, it's more important to get the driver to match the cab- as cab tuning is more of an issue with bass. Whether that's because of frequency or the sheer high power involved, or if it's one of those myths that get passed around...

This has to do with frequency. I've built and tuned a few ported enclosures, and the lower the desired frequency range, the tougher the enclosure is to tune. Enclosure design is far more critical with sub-woofer type applications (as well as the frequencies bass cabinets work with). For guitar loud speaker enclosures, all the same formulas apply, however, given the frquencies these drivers are designed to operate in, changes made in cabinet design have a less noticable impact on the sound. Ever notice how the changes you make to a guitar cab (or when a/b against a different cab) that the percieved changes generally apply to the bottom end?

Another wacky factor as far as cabs go is insulation. Something that was told to me that doesn't make sense, but I respect the professional credentials of the source, is that too much insulation can "fool" a speaker into behaving as if there's less pressure behind the speaker, rather than just taking up space or increasing the pressure behind the speaker...

Very true, although, insulation is most popular in small sealed sub-woofer enclosures. The idea behind the insulation is literally to control the air pressue in the enclosure as the woofer is moving air. By adding insulation, you can make an enclosure perform as though it was ~ 10% larger, resulting in a bigger, although not as punchy, bottom end. Insulation, like ported and volume, has less of an audible impact on higher frequencies. Additionally, you would not want to ever add insulation to a ported enclosure.

[Quencho092]

Re: Marshall JCM800 vs JCM2000 Series

Hmm does the plexi have a master volume? cause I won't really be able to turn it up full all the time... that's just too loud... this is mainly the reason why I'm looking into the JCM800 & JCM2000s.. the vintage series need to be cranked too much to sound good

If you're like me, then you have a cheap practice amp like a crate just to play on to go over stuff in your room and learn things/write stuff. I save my big amps (fender twin coming up!)for jams only, to me it's not practical to get an amp designed to sound good at bedroom volumes when you need it to sound good at jams and gig volumes.

Plexi is pretty much a clean amp at bedroom volumes. But if you need the marshall to get the marshall job done (stage concert or outdoor show, LOUD), expect it to rip serious classic rock tone!

[Quencho092]

Re: Marshall JCM800 vs JCM2000 Series

That sounds an awful like a "go big or go home" mentality... which is very tough to have when you are a younger player without a lot of cash flow Besides, half the fun of owning all this gear is modding it, right? I mean, that's why we're all interested in Seymour Duncan pickups, right? Or maybe we should have all bought guitars with Duncan pickups preloaded and "got it right the first time."

After my experiences modding and having amps repaired- NEVER BUY AND AMP THAT YOU NEED TO MOD, OR INTEND ON MODDING! Just get one that you like and has a warranty and enjoy it, once you start modding amps and stuff and things start to go wrong at jams and gigs, all the enjoyment of jamming disappears and you become fearful about your amp breaking every time. PLUS, it can be pricy to get amps modded and repaired anyway.

Guitars are a different story, they dont deal with harmful voltages, and almost anybody with a soldering iron and basic skills can put new pickups in. Not everybody is well versed in repairing dangerous amps, and not everybody has a couple of hundred bucks laying around to waste on having an amp modded by a tech and ruining its warranty. ENJOY PLAYING FIRST, guitar is about making musical connections between yourself and bandmates based on what you play, not on how much you have modded your gear or about how badass it sounds compared to stock or the other guitarrist's rig. Get something you enjoy playing through and is reliable, w/ warranty and play with no worries!

Sorry about the rant-just take the cost/hassle/benefit relationship of modding amps with a grain of salt. I would have been much happier buying a fender with reverb from the start instead of buying a head and cabinet without reverb and trying to have it modded.

[The Golden Boy]

Re: Marshall JCM800 vs JCM2000 Series

Sorry for the Thread Hijack!

Additionally, you would not want to ever add insulation to a ported enclosure.

That's interesting! My two older (pre-96) SWR cabs are both rear ported and have a white nylon type insulation covering most (if not all) interior surface area. I haven't had my 2x15 apart, and don't know if there's insulation in there, but it's also front slot ported.

Earlier in the thread I mentioned my 2x12. I've never had that cab sounding "good." It may be because I'm expecting to sound like a 4x12... It's a well constructed 3/4" plywood cab, the baffle is actually built into the cab (the only way to get the baffle out would be to disjoint the cab), and it's deeper than my Marshall 4x12. Another neat thing is 1/3 of the back removes . It came with chinsy speakers (mounted from the front) and the interior was lined with fibreglass insulation. It sounded like crap. I removed the insulation, it sounded poopy, I rear mounted the speakers, it sounded poopy, I replaced insulation, it sounded poopy. It sounds somewhat better with the back off, but it's missing some certain tone and an... immediacy to the sound (does that make sense?) Right now it's loaded with some old Sound City speakers (probably old Fanes- think 68-74), and those speakers rock, but not in that cab.

[MikeS]

Re: Marshall JCM800 vs JCM2000 Series

Lining three sides of a vented box can help in strengthening the upper frequency response of a speaker. However, care should be taken to keep the isulation away from the ports and voice coils.

In high wattage audio apps the lining is often avoided (primarily because the woofers used in vented enclosures are not designed for upper frequency response). Lining can, however, insulate the sound created by the "woosh" of air comming from the voice coil on a speaker with a long throw. I've found that insulation in ported enclosures is 99% of the time a band-aid for a minor design flaw or for an unforseeable nuance in construction. Like I said previously, insulation is far more prevalant in small-box sealed applications.