Mesa boogie problem!

[zombo]

I have a Digitech 2101 LE as a pre amp and as a power amp I use a mesa boogie 50/50!
I haven't used my power amp for a while and when I switch it on it all works fine however when I start to play my guitar through it the third valve starts to get red hot and then it blows my ht fuse any idea what could be wrong?
I am supposed to be playing tomorrow in my new band I am at a loss what it can be?

[Rick_Lamoreaux]

Dude, your wife isn't cheating on you is she, lol? :slider3:

[zombo]

Dude, your wife isn't cheating on you is she, lol? :slider3:

I was hiding behind the amp at the time!

[bluesgeek]

It sounds like its red plating for some reason, you need to get it checked out before you kill the o/p transformer :(

[zombo]

It sounds like its red plating for some reason, you need to get it checked out before you kill the o/p transformer :(

Excuse my ignorance but what is red plating?

[Guitarpima]

I hope you get it sorted John. I had an amp go the night before a gig once and was stuck using this Randall thing that made me sound like I was a misplace old style Beatle. For some stuff it sounded good though.

[HappySinner]

A good place to find info on all things Boogie is the Boogie Board (http://forum.grailtone.com), a Mesa/Boogie forum. There are some obsessive puppies over there, and there are tech guys that contribute as well. Worth a look. :-)

[TheGummy]

sounds to me like a dodgy valve/connection with the valve, i personally would get new valves and ge tthe bias reset just to be safe, but i'm far from any authority on this so don't take my word for it.

[Lyle]

None of us are having any luck with amps lately lol!

[TheGummy]

None of us are having any luck with amps lately lol!

true, time to get out the acoustic

[zombo]

I have found some amp guru by Truro not far from where I live so I will let him sort it out rather than twiddle!
Thanks for your help though it was much appreciated!

[bluesgeek]

good choice john, red plating happens when the bias is set too hot, it can destroy the valves pretty quickly. Sounds like a component in the bias circuit could be shot - which is why its started to red-plate. Definitely get it checked over, it may be an easy fix rather than a new set of valves!

[zombo]

Well I sorted it out I noticed that the active speaker emulator was on and this was overpowering my power amp causing the valves to get hot!

However after explaining this to Mr Danny Danzi he told me that he always had his on, but he used the XLR output.
So you need the xlr on the ends that go into the 2101 and on the other ends of those cables, they need to be TRS (tip/ring/sleeve) like a headphone jack, only they must be 1/4 inch
I had mono on mine causing the problem! Danny called it its a balancing system balanced and unbalanced cables.

So this problem is sorted thanks again especially Danny Danzi.

[bigdoug]

far to complicated for me.. glad you are sorted now mate, rock on :grin:

[Stew]

Very complex I think acoustic was best advice personally lol

[bluesgeek]

yep that would do it :lol:

[Mr Smith]

John dude, the problem is that you have a Messa and I dont :/

[Rick]

yeh same here.

[Danny Danzi]

Not a problem brother John. :) Yeah it's important with power amps when using XLR to keep it true XLR. When you have a hybrid cable with XLR on one end and a regular 1/4 jack on the other that would go into a power amp, you're defeating the purpose and literally making the amp work harder.

When you use XLR on one end and the headphone type 1/4 on the other end (used to be referred to as stereo ends, headphone type jacks or TRS...which is the current name meaning tip/ring sleeve which identifies the rings around the jack end...mono has one ring, TRS has 2) you are keeping the constant power of the XLR cable which in turn produces a cleaner and hotter singnal. This is only useful in power amp situations...so don't everyone run out and buy TRS leads! Hahahaha!

The other way you could have done this John would be to use the 1/4 outs of the 2101 using regular guitar cables right into your power amp. At least the signal would have been proper where the XLR with the regular ends was working the amp harder, making it sound strange and robbing it of power because it was a hybrid cable. Using the 2101 straight 1/4 is perfectly ok, but to me it sounds very harsh in this manner and you would most likely have to alter your global eq considerably to come out with a warm tone. Or, you'd have to introduce the speaker sim into an algorithym internally and you'd need firmware 3.0 for that. It's not as good as the push button speaker sim, but it gives you about 10 different cab options. The downside, it takes up processing power so you may not be able to complete an algorityhm the right way and something important might have to be sacrificed. Or, if you have dual s-discs, you may have to use both which would bring on a glitch in your sound when changing patches.

So just go with the cables I spoke to you about and you'll be fine. You'll notice a cleaner, warmer more consistent and more powerful sound, that's a promise. :) Good luck!

[zombo]

Cheers again Danny!

[TheGummy]

XLR to 1/4" Jack hybrid cables are terrible abominations of cables in my opinion, and should never be used!

[zombo]

XLR to 1/4" Jack hybrid cables are terrible abominations of cables in my opinion, and should never be used!

Utter rubbish I am glad I didn't take your advice!
So should I melt my amp then?
You obviously haven't heard my amp now I bought those terrible cables !!

[Danny Danzi]

Hmm I actually found Gummy's comment to be a bit alarming myself, John. Why do you feel that way Gummy and would you happen to have any information that would justify your feelings? I'd be interested to learn the scoop on this one.

When using a balanced output section using XLR, you need to keep the balanced signal flowing. If the other end of the input device sports 1/4 inputs, a TRS keeps the signal balanced and is every bit as potent as a true balanced on both ends, mic cable.

The cable must either have a transformer built into the cable (which I recommend when doing this procedure) or a transformer jack that plugs into the mono 1/4 end. These cables are absolutely incredible and offer a much better signal quality than standard 1/4 if you have a balanced option. If he wanted to run his 2101 into a mixing board, he has XLR outs in it. He can take 2 standard mic cables and run the unit directly into a board without a direct box. He also has 2-1/4 standard guitar outs. If he took these directly into the board there would be sound but it would be weaker, noisier and less consistent.

This same method is being applied to a power amp situation. If you have the ability to use XLR outs at any time, you MUST use them at all costs for better, hotter signal. Not to mention less noise and a considerable amount of volume and clarity. Power amps usually rely on XLR for the best sound quality. But eventhough a guitar power amp may have 1/4 inputs, balancing out the signal using TRS on one end and XLR on the other, makes the amp work less and sound better giving you more power, longer durability and more volume at lower volume believe it or not.

John's problem in this scenario was, he was unaware that TRS existed for this procedure and he didn't understand why it would make a difference. He was using XLR on one end, mono 1/4 on the other. This sent a hot signal to the power amp which the power amp accepted but could not return in the same fashion due to the mono ends being unbalanced. You can't ever mix and match balanced and unbalanced. You CAN do it to get you through the night, but it will make the amp work harder, get hotter and you will have less volume. Buying the new cables instantly fixed his problem.

For more information on this stuff, you can read about it from the Rane people. http://www.rane.com/note110.html

So it is perfectly normal to use this procedure and I personally don't see any abominations of any kind really. If you are a regualr amplifier man, it's easy to see where something like this may not seem important to you. But when you are a pre-amp into a poweramp man like myself and a few others, this is valuable information that literally improves more than just your tone. ;)

[TheGummy]

yes ive made a fool of myself there, i should have included the word 'mono' before '1/4" jack'!

i was agreeing with what you're saying, i've become quite familiar with TRS, XLR, balanced/unbalanced or mono/stereo and realised that the cheap XLR to 1/4 MONO jack cables dont do things properly for the reasons you stated above, and i understand that TRS cables are essentially the same as XLR, just with a different type of connection on each end.

sorry, im developing a habit of not explaining myself as fully as i should, which is a bad habit to have :|

[TheGummy]

as a sidenote, the reason i am so against XLR - 1/4" mono cables is because of my live sound experience.

at my old school its all we had for mic cables, and the signal was always terrible when we used long cables across the stage, with plenty of interference (because the interior cable is unbalanced, interference isnt cancelled out).

but learning from a live sound/acoustic genius we have at college, i now make sure i dont use any mono/stereo (or balanced/unbalanced) hybrid cable.

hope that explains things better, i feel a bit of an idiot now.

[Danny Danzi]

Yeah I can understand where you'd hate them in that manner. Once you are converted to 1/4 mono, the XLR part is really doing nothing. Every 20ft of chord you use, the more noise and less volume you pick up. However, a fully balanced XLR or full mic cable can be run for miles and plugged into itself to make it longer and there is little or no signal degradation....depending on the quality of the cables used.

Same for you guys with guitar rigs, amps, pedals etc. Keep your cables as short as possible at all times. Try to buy cables by measurement if you can. Especially those times when you want to patch something together. Every 20ft of cable leads to noise and about -3dB of sound for each 20ft. If you have a bunch of rack gear that's all racked up, buy those little 4 inch cables and get good ones so you reduce the chance of signal loss. The only long cables you can allow in your chain would be the cable coming from an amp into a pedal board, and the cable into your guitar so you can run around the stage. But try your best to keep them all as short as possible and buy the best quality you can afford. They really do make a difference. ;)

[bluesgeek]

Its worth noting the same for amp to speaker cables - get the best and thickest you can get, and keep them as short as possible :) It really does make a difference, if I can hear it, its got to be a big one!

Of course then I plug all my gear into a shonky old VHF wireless system that kills the tone anyway :lol: comes in handy when I need a beer though ;)

[TheGummy]

Yeah I can understand where you'd hate them in that manner. Once you are converted to 1/4 mono, the XLR part is really doing nothing. Every 20ft of chord you use, the more noise and less volume you pick up. However, a fully balanced XLR or full mic cable can be run for miles and plugged into itself to make it longer and there is little or no signal degradation....depending on the quality of the cables used.

Same for you guys with guitar rigs, amps, pedals etc. Keep your cables as short as possible at all times. Try to buy cables by measurement if you can. Especially those times when you want to patch something together. Every 20ft of cable leads to noise and about -3dB of sound for each 20ft. If you have a bunch of rack gear that's all racked up, buy those little 4 inch cables and get good ones so you reduce the chance of signal loss. The only long cables you can allow in your chain would be the cable coming from an amp into a pedal board, and the cable into your guitar so you can run around the stage. But try your best to keep them all as short as possible and buy the best quality you can afford. They really do make a difference. ;)

yep, thats another thing i've learned recently by doing more live sound on bigger stages, prompting me to buy more patch leads and a boost/signal buffer pedal, as well as looking out for pedals that buff the signal up as well as their primary function.

[Danny Danzi]

Its worth noting the same for amp to speaker cables - get the best and thickest you can get, and keep them as short as possible :) It really does make a difference, if I can hear it, its got to be a big one!

Of course then I plug all my gear into a shonky old VHF wireless system that kills the tone anyway :lol: comes in handy when I need a beer though ;)

So true Blues bro!!! I get the fattest speaker cables I can find. They really make a huge difference for sure.

You know why that wireless alters your tone so much man? I'll share a little with you. The reason for it is the radio frequency. Each radio band has to be compressed immensely to operate. You know how a radio station compresses their station to stay in the bandwidth, right? Same with the wireless only worse because they are not allowed to transmit the same way. It's like the wireless borrows part of the bandwidth to where it has to remain restricted. Therefore, your tone suffers with that compression. The first thing you notice with a wireless is usually a lack of high end due to the compression killing the highs, or at times too much high end because the compression kills the lows. They also alter your pure gain output....meaning, if you kill the wireless and play with a cable, you will notice more gain at the same gain setting on your amp.

The UHF wireless units are a bit different as they don't need as much compression to keep them within their bandwidth. There is a unit that does not color your sound to where you can't tell a difference between it and a cable. The downside of it is.....it's $5000 non-negotiable and you can't even try it. LOL!! Most stores won't even stock it because it's such a high ticket item, so when they have to order it, (it's a high end Sony by the way) you HAVE to buy it because Sony will not take it back.

The Samson Concert series stuff is really good too. The good thing about them is you can open up the transmitter and tweak the gain inside it. For the money, (about $400) it's the best wireless I've ever used besides that killer Sony system. I use the Samson in my little rig and the Sony in my big one. ;) Cmon Blues, you're a seasonsed pro mate....surely someone brings the beer to you when you're playing right? They better! ;) If I ever come and see you play, I'll be your lil beer boy. I line em up on the stage for ya faster than you can drink them. Hahaha! Man, I have so many beers lined up when I play, I wind up giving them out to people when I'm done because if I drink enough of them, I get sleepy. LOL!!

[bluesgeek]

I actually don't mind what it does to my tone too much, the amp I use is a bit too trebly anyway, its good to kill it ;) I got the wireless unit for free so I can't really complain too much :lol:

I usually get beer but last night we had 4 guitarists on stage at one point, so I went to the bar while they finished noodling.... fun times :lol:

[zombo]

as a sidenote, the reason i am so against XLR - 1/4" mono cables is because of my live sound experience.

at my old school its all we had for mic cables, and the signal was always terrible when we used long cables across the stage, with plenty of interference (because the interior cable is unbalanced, interference isnt cancelled out).

but learning from a live sound/acoustic genius we have at college, i now make sure i dont use any mono/stereo (or balanced/unbalanced) hybrid cable.

hope that explains things better, i feel a bit of an idiot now.

No problem I just found it strange you put that down!
I've put my foot in it loads of times so has everybody else it's ok or I didn't explain things properly your forgiven bro :-)