Bare Knuckle Pickups Forum
Forum Ringside => Guitars, Amps and Effects => Topic started by: Roobubba on August 14, 2007, 05:20:03 PM
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Hi all,
So, I've managed to pick up a beautiful Peavey 5150 mark II complete with an angled Peavey 5150 cab (ie half stack).
This is my first tube amp, so I have a few questions, the answers for which seem to be mostly eluding me (via google and the search here).
I thought it'd be useful for anyone else getting a 6505+ or 5150-II amp head to read the info that's likely to come here in response to my questions - I know how helpful and knowledgeable people are on these boards!
For info, the amp was used last night at band practice. The clean channel has got plenty of headroom, as has the distortion channel, but I'm getting really severe feedback and noise on the distortion channel at volume (I know I need to get an ISP decimator!)...
So here we go.
1) I picked up the amp/cab on Sunday, played on Monday as it was set up (didn't touch anything on the back). The output seems to be set to 8ohms, but I read elsewhere that the cabinet is 16 ohms. So, do I need to count myself lucky that the amp hasn't died, turn it over to 16 ohms and try again, or should it actually be on 8 ohms?
2) Valves. What valves do other users of this amp use? I have already found several links to goo places to buy valves, but I need this from one step further back, what valves should I get?! I'm after a brutal gain sound which is as tight as humanly possible, and with a minimum of hum and preferably NO FEEDBACK! I am aware that the valves will likely need changing. Is it fairly straightforward to bias this amp, or should I take it to a guitar tech. If guitar tech - can anyone recommend one in or near Oxford?
3) Feedback and noise issue. I'm not sure if this is related to valves in 2) above, but here we go. I know I need an ISP decimator, I'm looking at finances to decide when to do this. In the mean time, I am running my guitar through my zoom effects unit through the clean channel of the amp. This sounds surprisingly good, but you'll just have to take my word for that! Would a noise gate in the effects loop work well? Better before the pre-amp?
That's all for now. I had another one, but I've forgotten it!
Thanks in advance!
Roo
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Count lucky indeed, the 5150 is 16 ohms. Flick it over soon.
In the meantime, this might help:
http://www.peavey.com/search.cfm?c=5&term=5150
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you'd need to try the decimator both in front of the amp and in the loop, to see which you prefer.
Also, don't bank on the decimator cutting all your feedback, it may not suppress all the feedback you're getting.
(EDITED "loop" in place of "preamp" because i'm a retard)
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I've got a 5150mkII and an ISP Decimator - use it into the front of the amp for best results imo.
As for valves, the amp uses ECC83s/12AX7s in the preamp and 6L6s in the output stage. I've just done some research into current production 6L6s as my own 5150 could do with revalving - I got some Groove Tube GE-6L6s (recreations of the famous GE 6L6). I got them through BNB Tubes on ebay and paid around £75 in shipping which ain't bad at all considering Hotrox wanted around £120 for 'em.
As for ECC83s, I'd go with the JJ ECC83s.
:twisted:
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okay, about a noise gate, i'm going to reccommend the boss ns-2 as long as its in the loop. If the gate is infront of the amp, it only stops noise from the guitar, not the amp; AND gates arent meant for guitar level input so when the gate closes, you're likely to hear a metallic crackly sound. So i'd say keep it in the loop that way you can quiet down the preamp too.
Ns-2 is great because its small, easy to power, and has both a threashold AND a decay rate (isp only has threashold). I hear lots of people reccommending it over the isp pedal. The only thing i've heard that beats it is the isp decimator pro rack G, which is crazy expensive.
for tubes.
Preamp: either jjecc83-s's or sovtek 12ax7lps's. The sovtek is great for brutal technical death riffing, jj's are decent all around. I also find the lps's are great for phase inverters (better than the JJ's at least)
poweramp: SED winged "C" 6l6's for your tight technical riffing. Theyre great for heavy tones.
For biasing the poweramp, take it to a tech (the 5150II's are easier to bias than the normal ones) and ask him to bias them a little on the hot side, 5150's LOVE hot powertubes. And you dont need to bias preamp tubes, theyre just easy in and out.
As for the feedback, test the amp without the zoom. Then stand far far away from the amp and lay off the gain. With 5150's you really dont need the gain much past 2-3 oclock. They have too much anyway in my opinion :lol:
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Thanks for the responses - keep them coming, guys, the more the merrier!
Just wanted to respond to that last comment, bleeding - I've tried it without the zoom box, and the gain on 2-3 simply wasn't enough, it was like a crunch. Could this be due to old pre-amp valves?
Also, could the cabinet being run at 8 ohms have an effect on this?
I remembered one more question which I forgor originally:
4) When I activate the effects loop (tried with the zoom pedal on bypass, along with other effects, didn't try just a cable between send/return), the overall output was considerably lower. Again, will need re-testing when I've sorted out the cab to 16 ohms, but I was wondering if there could be something awry in the effects loop circuitry?
That's all for now, probably more to come!
Cheers again,
Roo
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Thanks for the responses - keep them coming, guys, the more the merrier!
Just wanted to respond to that last comment, bleeding - I've tried it without the zoom box, and the gain on 2-3 simply wasn't enough, it was like a crunch. Could this be due to old pre-amp valves?
Also, could the cabinet being run at 8 ohms have an effect on this?
I remembered one more question which I forgor originally:
4) When I activate the effects loop (tried with the zoom pedal on bypass, along with other effects, didn't try just a cable between send/return), the overall output was considerably lower. Again, will need re-testing when I've sorted out the cab to 16 ohms, but I was wondering if there could be something awry in the effects loop circuitry?
That's all for now, probably more to come!
Cheers again,
Roo
not 2-3. 2-3 OCLOCK. that would be around 75% :roll:
If you are running it like i say, and its not enough, its definately time for new preamp valves. And running the cab at 8 ohms can potentially have an effect yes. Keep your ohm ratings at 16 --> it drives your poweramp harder which gets you quicker breakup, heavier distortion, and fatter tone.
Are there any level/line controls for the loop? like a send and recieve leve? If not, then yes, something is probably wrong. If you take it to a tech and he says that they're all like this, then just set your effects so volume stays the same when you activate the loop.
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Hey
Ive had similar problems with the 5150 myself, love the sound - but its totally uncontrollable if you get the pre gain past about 5 and the post gain up to about 4.
I have a Decimator, which I use in the loop, if you use it infront of the amp then it wont have mcuh affect as your signal hits the amp after the decimater - which is where the feedback is.
I never use the high input, theres absouletly no need with the amount of gain on tap - I also had the inside of the amp screened -although i'm not sure how much that helped.
I would concentrate on getting some good quality 12ax7's Try somewhere like watford valves - i think thats where tim gets his from.
Rolling off the guitar volly helps a bit as well. The main problem with the 5150 is that it was made on the cheap; the valves fit directly onto the PCB and there is no internal screening - its just not put together very well.
It also doesnt like being near electrical equipment, - I have picked up german radio stations on mine - ive even picked up someone elses amp who was in the next room. I took it to an amp guy who told me it had 70 times more gain than a standard Marshall!
My 5150 had so much gain that it would make the pickups in my guitar vibrate in their pockets, which added to the problem.
The decimator will help - and although its prob the best foot pedal noise gate it will still suck a shitee load of tone and sustain if you set it past 12.
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I took it to an amp guy who told me it had 70 times more gain than a standard Marshall!
And that's why we love it =D
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My advice to you is to spend a bit more cash and get an ISP Pro Rack G
http://www.highlystrung.co.uk/acatalog/Online_Catalogue_Other_pedals___processors_171.html
(it's slightly cheaper on http://www.thomann.de/gb/isp_technologies_decimator_pro_rack_g.htm?partner_id=59917 btw)
It has 2 channels, one for the input and one for the loop... it's very clean and clear.
The pedal CAN be a tone sucker i've found and can make everything quite tinny depending on which amp im using.
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That ProrackG does look absolutely ideal... one point though - do you need a rack to mount it in, or can it just sit on top of the amp?. I don't want anything too big - it's already a bit of a pain lugging all this gear to and from rehearsals! I can't find anything that is suitable to house just 1U (I have no plans to buy more rackmount gear). Plus it's all quite expensive - this amp has taken a good deal of my disposable income for many months to come, add a further 250 quid on to that for the rackmount, and another 100 or so for tubes... eeek! Plus 50 quid for some poncey aluminium housing which I really would rather without, and you can see my dilemma!
Roo
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That ProrackG does look absolutely ideal... one point though - do you need a rack to mount it in, or can it just sit on top of the amp?. I don't want anything too big - it's already a bit of a pain lugging all this gear to and from rehearsals! I can't find anything that is suitable to house just 1U (I have no plans to buy more rackmount gear). Plus it's all quite expensive - this amp has taken a good deal of my disposable income for many months to come, add a further 250 quid on to that for the rackmount, and another 100 or so for tubes... eeek! Plus 50 quid for some poncey aluminium housing which I really would rather without, and you can see my dilemma!
Roo
The rack is just housing... Do you need an amp stand to use an amp?
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nah, you can even sit it under the amp, on top the cab! It's up to you where you stick it!
it's a great bit of gear if you, like me; play very fast and need a great deal of punch and articulation... but no hiss or hum
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OK, I've just been playing, and noticed quite a bit of noise. As I mentioned above, I'll try to sort out a tube change asap (eek cash!), both pre-amp and power tubes.
But, for my own information, three of the power tubes glow blueish when the amp is on and signal is through it, and the remaining power tube doesnt' go blue, just stays with the orange glow. Is it the one tube is likely to be dead, or the three blue ones? I've been letting it warm up for at least 5 mins before playing.
Also tied in with this, can anyone in or near Oxford recommend someone to take the amp to? I'll try to find amp techs asap, but again it's a cash issue!
Still, we've now got a gig in October (Oct 21th at the Port Mahon in Oxford) to look forward to and work for, so will get the amp fully sorted with noise reduction in place before then! If anyone fancies coming along to hear something truly brutal, watch this space for more details nearer the time :)
Roo
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that's backlighting I should think.
Modern amp manufacturers do it to make you feel that you are getting something of immense power.
Engl amps do it but in red.
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No, I mean the actual tubes - I can see them at the back of the amp. There's not much light coming from them, just a faint purple glow - from three but not from the forth. Anyway, I switched them round and gave them a clean while I was at it, see if that helps for tomorrow's practice. Man I need cash! :)
Roo
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5150's DO NOT HAVE BACKLIGHTS
the blue glow you see is the tubes functioning. If they arent glowing faintly blue, theres a problem. Might haeve to take it into a tech.
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I never came across a blue valve before :? .
usually they glow faintly orange...
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I might see if I can take a picture of it later. I swapped over the power tubes, and the same pattern was there - so it's not actually the one tube which doesn't glow purple, it's the tube position. Might need to play them for a while, get the hot and see if it's still there. There's the orange glow - as soon as you turn the power on, they start warming. Then, when you switch from standby mode to "on", and signal passes through (playing or not playing), three of them have a faint purple glow.
Would amp techs be listed under "repairs" in Yellow Pages? The amp sounds fine, apart from the usual amounts of noise, but that's a separate issue!!
Of course, if biasing is something I can do myself...
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The purple glow is perfectly normal, some valves have it more than others - I don't see it much in EL34s, but it's very common with 6L6s.
Read this for further clarification... http://members.aol.com/larrysb/blue_glow.html
:twisted:
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The purple glow is perfectly normal, some valves have it more than others - I don't see it much in EL34s, but it's very common with 6L6s.
Read this for further clarification... http://members.aol.com/larrysb/blue_glow.html
:twisted:
good site, i'm guna fire my marshall up and take a picture of it for you guys. It only glows blue when power is on and standby is off (sound can come through). Power turns on the heaters, standby allows current flow for sound, which in turn gets electrons bouncing around in the tube, which gives you the sexy blue glow. :D
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OK all,
had a bit of time with the amp. Still want to get some new tubes, but I've had a play around swapping the order of them to see if there's any difference.
This amp just doesn't seem to be very high gain. I got a lot more gain from my Randall RG200G3 combo, which I only got rid of because of the reliability issues.
As far as I can tell, the gain channel should be called a feedback channel.
What tips to people have for a) stopping completely uncontrollable feedback (other than ProRackG - I'll be getting one after pay day) and simultaneously b) getting a good gain sound?
I don't want crunch, I want full on metal!!!
Seems to me that tube amps simply weren't designed for heavy sounds...
So far I've been using the distortion sounds on my Zoom g2.1u effects unit in front of the amp and putting everything through the clean channel. This is stopping feedback (ie not the feedback... sorry gain channel), and giving me a decent level of distortion. It's not ideal, though - I'd rather have what I paid for - a high gain amp...
I should say that at extremely low volume (ie post down to completely minimum), the sound from turning the pre-amp up to about 7+ is really nice, decent level of gain and of course no feedback at that volume. When the post is turned up, the level of gain just seems - weak... Surely the power amp should just essentially turn up the volume (up until it's near breaking up) of the pre-amp gain sound? I don't understand why at any reasonable volume, the gain is much less than at 0 volume on the post.
If anyone can shed light, or provide ideas for how to resolve this, I'd be most grateful.
I should point out that I will - in the next few weeks, as and when I can afford it - get a whole set of new tubes (hell, I'll need them some time) and an ISP decimator ProRackG. But I'm guessing that noise suprssion isn't going to resolve the gain issue. Do people use overdrive pedals in front of their peavey 5150-IIs? Sounds to me like it just needs a whole lot more gain, and a whole lot less feedback!
Roo
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You're kidding right?
Not enough gain on a 5150?
There must be something wrong with your amp.
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Isn't the 5150 the gainiest stock amp ever??
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yeah... it's 'normally' ridiculous.
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Mine doesn't feedback badly at all and has more gain than you could ever need.
There must be something wrong with the preamp valves in your amp (or something up with the amp itself) if you're having problems getting enough gain.
* What about the cables you're using?
* Pickups?
* How close do you stand to your amp?
:twisted:
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I'm using shielded Planet Waves cables (have tried with other cables too, makes no difference), miracle man pickups in a Ibanez RG470F guitar, and I can stand up to 20 feet away (with the one 20' cable I have) and still get lots of feedback at high post volumes. There seems to be no attentuation of feedback with distance up to 20' (furthest I could try in the practice room!). It's not constant - but it happens after every note is stopped, and sometimes I have to turn down the volume knob on the guitar to get it to stop altogether, otherwise it carries on, even with the strings damped. Makes for impossible playing when you play a lot of stopped-note fast riffs - at least at volumes required for band practices.
Cheers,
Roo
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Are your pickups potted?
That seems to be microphony.
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have you taken it into a tech yet? if and when you do, ask him to check if the feedback loop has been cut. (i'm not even sure that 5150's ahve feedback loops, but its worth a try)
Another good thing to do is fire up your amp and grab a pencil. Tap each preamp tube very lightly with the eraser of it. if it makes a sound, the tube needs replacing.