Let’s talk about mid-‘70’s 50 watt Marshalls: 4 inputs (non master volume) with Printed Circuit Boards

[topekatj]

Been a Fender guy since I began playing but have gotten a weird ITCH recently to buy a 50 W Marshall! Don’t have crazy money for a ‘73 or earlier PTP amp. How do the PCB 4 holer’s stack up? Also, short of some hack job master volume mod, what’s the best current technology to dettenuate the volume for household use? I’m aware of the Weber MASS units — is there something superior?

Thanks

[Hbom]

Bad Cat Unleash works pretty well. But it will never do what a large room and 12" speakers pumping air do.

 

[bubs_42]

I would also recommend the Unleash V2. You can take down the volume very well, it also has and effects loop that comes after the amp and before the speakers. Easy to transport compared to other models that cost close to twice the money. 

[Jakeboy]

+1 on the Unleash….I have V2 right now and have owned V1. GREAT products.

I am trying to raise money now for something plexi-ish myself….

 

[bubs_42]

1 hour ago, Jakeboy said:

+1 on the Unleash….I have V2 right now and have owned V1. GREAT products.

I am trying to raise money now for something plexi-ish myself….

 

Have you thought about prostitution? 

[Travis]

2 hours ago, bubs_42 said:

Have you thought about prostitution? 

I’ll send @Jakeboy $1 to keep his clothes ON…

[HamerCustomEr]

8 hours ago, Hbom said:

Bad Cat Unleash works pretty well. But it will never do what a large room and 12" speakers pumping air do.

 

Including giving you tinnitus!

[BoogieMKIIA]

I’ve got one. It’s so damn loud I haven’t played it for some time. I have not played an older PTP version to compare, but it sounds great. Cleans are very nice and you can get slight to screaming distortion. Of course, the overall volume is not controlled unless you have a power soak device,

Three key points -

1. It lets your guitar sound like your guitar. A lead Boogie channel can sound similar with different guitars. Not with my 50W Marshall.
2. The dynamic response to your guitar with amp volume between 8 o’clock up to about 1 o’clock is really nice. Pull back on your guitar known and it drops to rhythm volume nicely. Great for when amps are not mice’s like back in the day.
3. Jumping the channels is lots of fun. If you only use the bass channel, crank it up past 2 o’clock and more high frequencies come through. Live at Fillmore East vibe. 

[Jakeboy]

1 hour ago, Travis said:

I’ll send @Jakeboy $1 to keep his clothes ON…

Damnit! And here I was all ready to order some thigh-high go-go boots and edible undies….

[gtrdaddy]

1 hour ago, Jakeboy said:

Damnit! And here I was all ready to order some thigh-high go-go boots and edible undies….

Don't thank me, thank @Travis

[Jakeboy]

Didn’t Nugent wear one of those in the 70s?

[topekatj]

9 minutes ago, gtrdaddy said:

Don't thank me, thank @Travis

Fall 2021 HFC Supporter 

[Dutchman]

I would look at a clone PTP amp in the flavor of Marshall you seek. The pcb models are considerably harder to work on and have many internal push on connections. They can be repaired.   But from my experience they're a pain in the butt. But so are Boogies... and just about all new tube amps these day's. A well built clone is about the same price.

[Travis]

6 hours ago, gtrdaddy said:

Don't thank me, thank @Travis

You forgot the front…

 

[bubs_42]

Have you ever started something and wished you hadn't? 🤣

[topekatj]

11 hours ago, Dutchman said:

I would look at a clone PTP amp in the flavor of Marshall you seek. The pcb models are considerably harder to work on and have many internal push on connections. They can be repaired.   But from my experience they're a pain in the butt. But so are Boogies... and just about all new tube amps these day's. A well built clone is about the same price.

Thanks for the recco, @Dutchman -- Do any PTP clones come to mind? 

I realize that 50 watts of anything would need an attenuator for household use. But nonetheless, a 50 W PTP amp would be badass, and sometimes we want what we want. 

I've checked out some videos of the Marshall 'studio series' amp over the weekend. They sound pretty good and notion of a 2x EL34 amp producing 5-20 watts is appealing, but talk about a nest of PCB. Aren't PCB mounted pots a bad idea? 

[Dutchman]

PCB mounted Pot's and tubes is just looking for trouble. There's some good ones out there. Ceriatone makes some fantastic Marshall clones, I have a 18 watt EF 86 TMB model I bought from somebody here. I tore into it to check it out! The build quality was as good as any I have seen. I think there's a few Marshall models on reverb now. I've been kickin' around building a JTM 45 this winter. There's some good kit's out there. Mojotone comes to mind and I might get their kit and tweak it to original JTM spec's if there is such a thing. I've got gut shot's I've been saving for years of old JTM 45's and they're all a little different. I think they used what was available and cheap, just like Leo!!

[Jakeboy]

9 hours ago, bubs_42 said:

Have you ever started something and wished you hadn't? 🤣

What comes around goes around. Serves you right!  😁

[stedge]

I am not actively looking for this kind of amp, but just interested, generally.  Based on what I read, lots of options but I kinda like the suhr sl67. Good company, it will be reliable and fixable, etc.  

 

another great 50w amp of an earlier era is hiwatt (504) and they really are built like tanks. Great pedal platform or w an attenuator can be bliss.  If you have never seen the inside of one of those, google it. As amps should be.

[mrjamiam]

On 9/13/2021 at 12:33 PM, topekatj said:

Thanks for the recco, @Dutchman -- Do any PTP clones come to mind? 

I realize that 50 watts of anything would need an attenuator for household use. But nonetheless, a 50 W PTP amp would be badass, and sometimes we want what we want.

The old Traynor YBA-1 is very nearly a Marshall, circuit-wise.- you can look it up.  Of course going that way would give you all the old amp experiences, like probably needing to re-cap, adding a 3-prong power cable and grounding the chassis to avoid the possibility of sudden death, and smoky aromas.  I've heard of other clones that were produced over the years, but I don't think there were lots and lots of them, and if they have fans then they probably have some collector value that prevents them from being super-cheap.  But very likely cheaper than anything with Marshall on it.

ETA - And of course they are all copies of the Fender Bassman at heart, most definitely including the Marshall.

[0054]

The earlier the Traynors, the more Marshall clone they are. LOUD lives there in these amps!!

[Disturber]

Best advice, try to find a reissue 1987x or one of the quite rare JCM800 1987's. They sound pretty damn good too both of them. Or if you can live with a bit less gain, buy a reissue JTM45. Or a reissue Bluesbreaker combo, they are killer.

 

Here is the gut of a 1972 50watter JMP.

Here is the gut of my 1973 50w JMP

They look pretty similar. I'm no tech. But I don't think you'd here much difference in a band situation. I think the later ones had a higher value on the bright cap which makes them more aggresive. That is a easy fix to put a lower value there. My bright cap says LEMCO 5K. Someone had snippet one leg when I got the amp and it sounded a bit dull. With the bright cap back in action the amp spanks ass.

[Biz Prof]

1 hour ago, Disturber said:

or one of the quite rare JCM800 1987's.

This, I can personally corroborate.  Never knew how rare these beasts were until recently.  Bought mine for the HFC-approved price back in early '93.  They have a ton of headroom at lower volumes (especially with the inputs jumpered), but plugged into the top "Vol 1" input with that volume on ~6 or so.....it's pure Marshall roar. 

[topekatj]

5 hours ago, Disturber said:

Best advice, try to find a reissue 1987x or one of the quite rare JCM800 1987's. They sound pretty damn good too both of them. Or if you can live with a bit less gain, buy a reissue JTM45. Or a reissue Bluesbreaker combo, they are killer.

 

Here is the gut of a 1972 50watter JMP.

Here is the gut of my 1973 50w JMP

They look pretty similar. I'm no tech. But I don't think you'd here much difference in a band situation. I think the later ones had a higher value on the bright cap which makes them more aggresive. That is a easy fix to put a lower value there. My bright cap says LEMCO 5K. Someone had snippet one leg when I got the amp and it sounded a bit dull. With the bright cap back in action the amp spanks ass.

Wow, a ‘73 with a PCB. 

[Disturber]

34 minutes ago, topekatj said:

Wow, a ‘73 with a PCB. 

After August or there around the 73's came with PCB boards. Just as great. Components were the same more or less.

[topekatj]

As I was originally creating this thread I was watching a '77 1987 model online -- it had the transitional cosmetics b4 the JCM 800 1987's: Bigger logo, and a big bead of white piping across the front. I remember seeing Robin Trower playing though a pair of fawn colored heads like that. At any rate, I watched the '77 disappear while I was pondering the buy. Ya snooze, ya snooze.

I also learned recently that Marshall built the some of the 1st gen MV heads in the old/original looking (plexi style) head cabinets. Obviously they're not four input units.