YJM100 vs. JMP

[Oldie66]

Hi,
After reading all your post, I will write only 2 my cents.
Today I compared YJM100 with vintage JMP 1971 PTP small box.
Well ... As we all know, plexi must be cranked. 100% true.
EPA or not , attenuator or not. The best sound you get without it.
Plexi is not bedroom amp!. Both amps with the same settings with
Mesa Horizontal 2x12 cab (Vintage 30 and G12C). EQ presence 0, bass 7, middle 7, treble 7, volume 7,5 not jumpered only top left used.
YJM on 50 W mod, EPA off. Only tube distortion.
Aracom attenuator 4 step down. Both amps.
No attenuated YJM was louder than no attenuated JMP.
What about sound?.
IMHO - old JMP was warmer, fuller, woody in tone.
YJM100 was more harsh, brighter, more modern sounding.
but I was surprised as good YJM100 sounds goes full 100 W option.
Very good, better as 50 mode. Fuller, warmer close to JMP.
(but I notice both holes jumped)
I can say with 50 W was a hungry dog but 100 was a screaming lion!.
Maybe this is it. Difference in 50 and 100 W Marshall amp. No experience with
old vintage Super Lead. I agree with another fans, YJM should be live gigs animal.
About EPA. Very helpfull but sound with Aracom is more my cup of tea.
By the way all the best to members.
PS. Used only CS LP 59 Reissue , Monster cable. Recorded at home by irig recorder.

All comments are welcome.
Please about sound not playing.
PS. Since 1985 no player. No time.....
But started again!!!

[Mat_P]

Jumper the channels to get more warmth out of the YJM.
We play a YJM and a JMP2203 side by side in our Lizzy cover band.
There's no way that the JMP is warmer or better in any way, there are pretty much on same eye height each doing what they are known for with the YJM having the dynamic edge.
The EPA is gold. Better than any power soak I've heard.

[Oldie66]

Finally hope...

[soundcloud]http://soundcloud.com/oldie66/jmp-1971-50w[/soundcloud]


[soundcloud]http://soundcloud.com/oldie66/yjm100-50w[/soundcloud]

[soundcloud]http://soundcloud.com/oldie66/yjm100-jumped-100w[/soundcloud]

!	Message from: surfnorthwest
	I fixed it for you, next time click on the Soundcloud icon on the toolbar then paste your link between the brackets. Here is an example [Soundcloud]paste your link in here[/Soundcloud] Surf

[surfnorthwest]

Not the best recordings but I'll play. Out of those clips it is hard to pick a winner due to the recording but if I had to pick one I liked the 71 JMP best. Yes is was warmer, but this can have a lot to do with the tubes and the settings. A 71 JMP 50 is the holy grail of the Marshall vintage sound to some, I have a friend who clones amps after this model.

You are right that both amps are not for the bedroom and should be opened up.

[Oldie66]

Thanks Surf.

JMP - old original TESLA El34 tubes.
YJM100 - stock tubes

[John 14:6]

Thanks Surf.

JMP - old original TESLA El34 tubes.
YJM100 - stock tubes

Rmove the stock Chinese Shuguang 12AX7 tube from the YJM100's V2 second gain stage spot, and replace it with a JJ 12AX7. That should get rid of any harshness in the YJM100.

[John 14:6]

Jumper the channels to get more warmth out of the YJM.
We play a YJM and a JMP2203 side by side in our Lizzy cover band.
There's no way that the JMP is warmer or better in any way, there are pretty much on same eye height each doing what they are known for with the YJM having the dynamic edge.
The EPA is gold. Better than any power soak I've heard.

A preamp tube swap will warm up a stock YJM100 for sure. The EPA beats the tar out of any attenuator I have ever tried or owned.

[Mats A]

The YJM in 50W mode can never sound exactly like a 50W amp since it has a 100W transformer, 100W output circuitry and you just shut off two valves.

[John 14:6]

The YJM in 50W mode can never sound exactly like a 50W amp since it has a 100W transformer, 100W output circuitry and you just shut off two valves.

I don't think anyone can actually here the difference live or in the studio. Every 50 watt Marshall might not not sound exactly the same in the first place. Same thing with 100 watt heads. My YJM100 sounds different for sure in the two power settings. I don't think a cranked 50 watt 1987x would sound too much different than a cranked YJM100 in the 50 watt mode. They both would sound like cranked Marshall Plexi's. The player would need to decide which one they preferred. That choice would most likely vary from player to player.