Musicians Roadhouse

Most attenuators suck tone and I have owned the Rivera Rockcrusher too. The Rockcrusher beat up on the the THD Hot Plate and the Marshall Power Brake I owned, but the Rockcrusher still had an unnatural sound to it. They all did. The EPA on the YJM100 sounds very natural. The YJM100 is a decent loud bedroom amp though it starts to really shine as you turn it up. Once your get the EPA up to about the 10:30 (clock face) the amp starts to sound more like the amps on your favorite records and it does get pretty good distortion un-boosted at that point. By the time you get the EPA up to the 11:00 - 11:30 position you have reached tonal bliss though this is a volume loud enough for a good size rock club gig.

If you play small bar gigs you should be able to push the EPA to the 10:00 or 10:30 position. You can do 11:30 or 12:00 (or more) for loud rock club gigs. I can even play with the EPA at about 10:30 or 11:00 at church, but we do get pretty loud. I am miced and going through the PA as well. if someone is playing rock gigs and cannot get their YJM100 up loud enough to sound good then maybe they should think about using another amp or a smaller amp for gigs like that.

EPA on 10:30 is pretty loud. Still i don´t agree on this how much an attenuator changes the tone. If you play a 1959 Marshall dimed without any attenuation it´s so stupid loud that you really can´t hear how it sounds. It´s so LOUD! Also the speakers get pushed a lot wich changes the tone a bit. If you use the EPA you only dime the power tubes not the OT. That affects tone. Using an attenuator pushes the whole amp just like playing on full blast. The louder you can have the EPA the better it sounds. But that is because you get closer to not usimg any attenuation. If you have it on 11:00 o´clock the OT only gets about 20-25 Watts. Still the most important thing is if you think it sounds good. Then it doesn´t matter how you do it. But it´s a fact the EPA Changes the tone and takes away a lot of the distortion when used on lower volumes. For me it dorsn´t matter if a have the tone but not the distortion. I don´t like to use overdrive pedals. A well known amp modder here in Sweden has modded a few AFD amps. He takes away the EPA and makes it in to some other control. He Thinks it trashes the way the distortion sounds. EPA is a chip that regulates the voltages to the power valves. Marshalls EPA is a cheaper not as good version of the London Power Scaling. I don´t remember what is was that the LPS did that the Marshall EPA doesn´t. When i had the AFD i thought it almost sounded better with EPA low and using it like it had a regular master volume than using the EPA. The tone got a Little bit fatter maybe when using the EPA. But it did something to the distortion.

I loved the YJM since the day I first heard it played at the 2012 NAMM show

Even with EPA at 12:00 the tone is clean. Yeah it sounds great if thats what you are going for but there is barely any crunch!
Its just a completely different amp with my rock crusher, roars like a plexi should!
My tone sweet spot is at 11:00 volume, no epa and no attenuator, of course this is way too loud. With the rockcrusher it still sounds amazing at normal practice levels!!!
There is no way you can get VH tones with the epa, but with a decent attenuator it behaves like a killer plexi should!!!

Either i'm going def or my YJM is broken, but EPA on 11:00 is a nice practice volume for me. I wouldn't say its too loud.

Mats A wrote:EPA on 10:30 is pretty loud. Still i don´t agree on this how much an attenuator changes the tone. If you play a 1959 Marshall dimed without any attenuation it´s so stupid loud that you really can´t hear how it sounds. It´s so LOUD! Also the speakers get pushed a lot wich changes the tone a bit. If you use the EPA you only dime the power tubes not the OT. That affects tone. Using an attenuator pushes the whole amp just like playing on full blast. The louder you can have the EPA the better it sounds. But that is because you get closer to not usimg any attenuation. If you have it on 11:00 o´clock the OT only gets about 20-25 Watts. Still the most important thing is if you think it sounds good. Then it doesn´t matter how you do it. But it´s a fact the EPA Changes the tone and takes away a lot of the distortion when used on lower volumes. For me it dorsn´t matter if a have the tone but not the distortion. I don´t like to use overdrive pedals. A well known amp modder here in Sweden has modded a few AFD amps. He takes away the EPA and makes it in to some other control. He Thinks it trashes the way the distortion sounds. EPA is a chip that regulates the voltages to the power valves. Marshalls EPA is a cheaper not as good version of the London Power Scaling. I don´t remember what is was that the LPS did that the Marshall EPA doesn´t. When i had the AFD i thought it almost sounded better with EPA low and using it like it had a regular master volume than using the EPA. The tone got a Little bit fatter maybe when using the EPA. But it did something to the distortion.

Opinions vary Mats and I completely disagree with you usual YJM bashing stuff. Attenuators are a joke in my opinion.

Squidhunter wrote:Even with EPA at 12:00 the tone is clean. Yeah it sounds great if thats what you are going for but there is barely any crunch!
Its just a completely different amp with my rock crusher, roars like a plexi should!
My tone sweet spot is at 11:00 volume, no epa and no attenuator, of course this is way too loud. With the rockcrusher it still sounds amazing at normal practice levels!!!
There is no way you can get VH tones with the epa, but with a decent attenuator it behaves like a killer plexi should!!!

I suggest you find a good service tech in your area if you still own a YJM100. It sounds like yours may need a trip to the amp doctor.

I've had two and i can assure you i know when there is a problem with an amp. I don't own a YJM anymore. I'd rather have a 1959 and my Power Brake. The YJM sounds best dimed like any 1959 amp. If you like using distortion pedals it can work on more human volumes. But since much of the distortion and compression is lost when you turn down on the EPA it doesn't work for me anyway.

Man thats exactly what I was thinking, selling the YJM100 for a 1959HW. I initially bought the YJM100 for all the bells and whistles, turns out I dont like the epa and the boost really sux (just my opinion).
Would be nice to have a simple HW circuit!

Sounds like a good idea!

Or maybe the Vintage Series SLP. It has an effects loop and that can be very useful.

Have pulled the trigger and listed the YJM on EBAY Australia!!!
I have got gas "Big Time".......Metropoulos Amps METRO-PLEX!!!!!!!
https://www.youtube.com/watch?v=5uJ9jG9 ... e=youtu.be

It ain't a Marshall:-)