Strange but true...

[rblyn]

Ok, so I've had quite a bit of run time with my two RM100's but havent used one of them in a while...(one is the metal grille, other is the solid face, looks like the Hammet version) I've noticed that my RM100M sounds WAY BETTER?? Meatier and definitely cleare than the other using the exact same EXACT premp/power tubes and modules..Same density/presence...same EQ...everthing matched exact....It hit me pretty hard this week when I switched them out due to sheer boredom (i had been using the hammet style for months while the other collected dust) I couldnt believe the difference!! Its almost like getting a new amp??? I was determined to narrow it down to tubes/cables/guitars but it IS the amp!! FWIW- The series loops are different as well- I have to change my send and return levels on my GT10 (using 4CM) because one of the heads has a much hotter loop- WTH?? Are the builds that inconsistent with these Randalls????

 

[Mike361]

So the next question would be what is different? Are the components the same, what are the manufactures dates. You are saying the black metal grill is the better sounding of the 2, so there has to be some updates or something. We all want to know. Or could there be something wrong with the other one. Keep us informed this is interesting.

 

[rblyn]

So the next question would be what is different? Are the components the same, what are the manufactures dates. You are saying the black metal grill is the better sounding of the 2, so there has to be some updates or something. We all want to know. Or could there be something wrong with the other one. Keep us informed this is interesting.

I can tell you that both have a clean bill of health and have been checked out by an authorized Randall repair center....the one I had been using was checked out very recently so I know its in good working order....Either there were some updates or there is some kind of inconsistency in the production of these....I cant tell any difference on the boards or amps but then again, I dont have a trained eye for that. The metal grill RM100 serial number is missing- It was written with a sharpie apparently? its rubbed away now... The other starts with 09 and is a sticker. The solid front head says "RM100-B 11.24.04" on the board behind the middle module...The metal grille just says "RM100-B" and nothing else.

 

[Kapo_Polenton]

Probably a difference with the presence board values for one.. start there! Does the bad sounding RM100 sound dull, no clarity?

 

[Mattfig]

I can only say that I can relate to your issues and what stands out to me is that you had to change values on the GT-10 between heads...I would focus my energies there but that's just me.

I'll also ask the standard questions...Same cab, config, cables using same inputs, same exact tubes and not just tube manufacturer??? Etc...I'm guessing you have already checked that out but just in case you didn't...Doesn't hurt to look one last time... :wink:

 

[BigBrewtus]

The KH was supposed to have something extra with its build
according to a Randall Rep that had posted on here. He wouldnt
disclose what the differences were. May have just been a sales
pitch. hahaha

 

[rblyn]

I can only say that I can relate to your issues and what stands out to me is that you had to change values on the GT-10 between heads...I would focus my energies there but that's just me.

I'll also ask the standard questions...Same cab, config, cables using same inputs, same exact tubes and not just tube manufacturer??? Etc...I'm guessing you have already checked that out but just in case you didn't...Doesn't hurt to look one last time... :wink:

We think alike Matt :wink: but I am talking pure cable to guitar differences in tone...I referenced the loop/Gt10 differences as an additional issue but i am testing straight to the guitar here when talking of the tone differences. Once I change the send/return values as needed, the metal grill amp still kicks *** on the other one??.....and yes, everything is the same, I have gone nuts over this checking to see what I forgot- but its just different.

Kapo- The "duller" sounding head still sounds great! I was plenty happy with it and have been gigging with it and getting rave reviews. Its just that the metal grill amp just sounds better. Its totally obvious, even to my other band members...Strange...

Brewt- I did hear about the KH's having differences in there but this is actually an RM100 that has the same look as the KH- I actually like the way it looks better, thats why Ive been using it as my main rig.

 

[Whoopysnorp]

I recommend you pull out the little PCB that has the presence and density pots (which is easy and takes all of a couple minutes) and compare the pot values. If they're different, there's your answer. Later-production RM100s got these parts updated for a clearer, less woofy sound. I changed out the pots on my RM100 for the updated values.

 

[eyeball987]

I had two RM50 combo's and both had the darker tone. It worked great for some tones and not so great for others.

I traded one of the combo's for a RM100 head that ended up not having this issue and simply liked the clearer and brighter tone better.

I moved the other combo and picked up a 1 of 3 RM100 KH's. After some talk with the Randall rep at the time, the only difference with the KH was a small tweak to the low end and different transformer that Kirk preferred. He mentioned something about possibly using some better components but wasn't sure. I don't know.

I A/B'd the KH to the other RM100 head I had and they sounded identical to me. FWIW.

 

[Jaded Faith]

I recommend you pull out the little PCB that has the presence and density pots (which is easy and takes all of a couple minutes) and compare the pot values. If they're different, there's your answer. Later-production RM100s got these parts updated for a clearer, less woofy sound. I changed out the pots on my RM100 for the updated values.

This is my reply 100% spot on. I can upgrade this PCB for you for $30 in parts/labor/shipping and it's a 1-day turnaround.

Ironically, I just had a customer that greatly prefers the older/woofy values. Different strokes for different folks, but that was certainly a minority opinion in my experience. I have done many of these and get nothing but praise about how much better the amp is afterwards. Sounds exactly like what you are explaining when comparing the two heads side by side.

 

[JeffHenneman]

I have a Rm100 and a Rm100KH. I am not sure how old the rm100 is, I bought it brand new a few years ago, but I prefer it over the KH.
I know the about the talk on here of the KH being a little different, the main thing I remember is it having more low end or something like that. The rm100 seems to be a little beefier and more of a full sound. Although my SG diablo sounds the best in the KH.
I guess my point is that the strangness with the MTS amps is everywhere. Plus it may just be different preferences as JF said.

 

[Slashpepper]

I'm pretty sure mine is the old version too, have to turn the presence right up and it still sounds more like Rock & Roll rather than metal. Still good, just different. Sounds like we're in the same position.

How hard's the density/presence board to take out? I really want to mod it but I'm scared of getting electrocuted... Wondering if I should just take it to the local amp repair.

 

[Whoopysnorp]

It is very easy to remove the board. All you need to do is remove the chassis from the head box, remove the density and presence knobs and undo the nuts holding the pot shafts to the chassis, and then the board slips right out. It will still be attached to the rest of the amp with a pair of molex connectors; I recommend snapping a photo of these before you unplug them so you know which plug goes in which socket when it's time to put it back together. The plugs might be a little reluctant to come loose from the sockets; don't pull them by the wires if this is the case. Use a pair of channel locks or pliers to grasp the plastic plug part of the connector instead.

This board isn't anywhere near any dangerous capacitors, but nevertheless, exercise basic caution when doing this. Make sure the amp is unplugged, and don't go poking around anywhere you don't belong.

 

[Rod]

Wow... This explains why I always disliked my older Lynchbox 100 head compared to my newer 50 watters.
now I know why

 

[Daryl]

I recommend you pull out the little PCB that has the presence and density pots (which is easy and takes all of a couple minutes) and compare the pot values. If they're different, there's your answer. Later-production RM100s got these parts updated for a clearer, less woofy sound. I changed out the pots on my RM100 for the updated values.

This is my reply 100% spot on. I can upgrade this PCB for you for $30 in parts/labor/shipping and it's a 1-day turnaround.

Ironically, I just had a customer that greatly prefers the older/woofy values. Different strokes for different folks, but that was certainly a minority opinion in my experience. I have done many of these and get nothing but praise about how much better the amp is afterwards. Sounds exactly like what you are explaining when comparing the two heads side by side.

That sounds cool. I have an older RM100 that has been wicked reliable so far, but I am curious as to whether or not that PCB would be a good mod for my RM. Shipping it to NJ would be insanely expensive from the West Coast. How much for the PCB all by itself?

 

[Jaded Faith]

How much for the PCB all by itself?

About $2-3. It's about 3" square and about 2oz of weight.