DRRI - reverb send/return valves need replacing?

noisepolluter

Ongoing crackle, not present when reverb switched off. The valves have been in there since I got the amp which I think must be two years ago now, and I suspect they were in there a while before that.

ICBM

Could be just interference being picked up by the tank transducer, or a bad contact in the tank.

If it's a valve it will be the return one, V4 - next to the reverb transformer on the side closest to the power valves. Swap it with V1 - if the problem doesn't go away it's not the valve.

noisepolluter

Will give it a go, ta. 

You've got me bloody well looking at MOD reverb tank upgrades now. *shakes fist*  

This looks good. 

http://www.amplifiedparts.com/products/p-rmod-4ab3c1b

Dan

Ive got a similar issue with my DRRI. Will keep an eye on this thread.

ICBM

noisepolluter said:

You've got me bloody well looking at MOD reverb tank upgrades now. *shakes fist*  

This looks good. 

http://www.amplifiedparts.com/products/p-rmod-4ab3c1b

It does at least not have the design fault of modern Accutronics tanks which causes them to fail.

It's unlikely it will be any less noise-prone if the tank does turn out to be the cause though. It's not the type of tank that's the problem, the transducer is essentially a single-coil pickup, so any noise and interference in the environment will be amplified by the reverb recovery stage. If you think it might be this, try moving the amp around and see if the noise changes or goes away.

Van_Hayden

Depending in the age of the tank leave alone. Older accutronics are more often than not better sounding than the MOD ones. Unless you like dark verb...

noisepolluter

To be honest I think the reverb sounds great already. It's just that greedy little part of me thinking "What if I could make it sound even more brillianter...?"   I do also have a Digitech hardwire reverb for when I want variety.

I'll try playing it in a different place first of all, then checking the tank's plugged in properly, then swapping the valves. Thanks all for your input. 

benecol

noisepolluter said:

Will give it a go, ta. 

You've got me bloody well looking at MOD reverb tank upgrades now. *shakes fist*  

This looks good. 

http://www.amplifiedparts.com/products/p-rmod-4ab3c1b

Funnily enough, I bought one of those last month for my Princeton, but turns out my original tank is fine (thought it was the source of some buzzing - it's not). Yours if you want it for a smidge less than what I paid for it (and no embarassing customs fees like I had to swallow - revalved as well, see).

noisepolluter

benecol said:

noisepolluter said:

Will give it a go, ta. 

You've got me bloody well looking at MOD reverb tank upgrades now. *shakes fist*  

This looks good. 

http://www.amplifiedparts.com/products/p-rmod-4ab3c1b

Funnily enough, I bought one of those last month for my Princeton, but turns out my original tank is fine (thought it was the source of some buzzing - it's not). Yours if you want it for a smidge less than what I paid for it (and no embarassing customs fees like I had to swallow - revalved as well, see).

Thanks for the offer - will try the fixes above and if get back to you if no joy.

benecol

Aye, no probs.

noisepolluter

Looks like it may actually be interference of some kind from where it's usually sat - moved it to another room and didn't notice the crackle. I did check everything was seated/connected properly too though. 

It's usually sat next to, and plugged into, a surge strip with other (much lower draw) bits and bobs also plugged into it - e.g. hi-fi separates, boss pedal PSU etc. I'll try it directly into the wall socket in the same place and see if that's any different, and if so maybe look into some kind of power strip with better screening.  

noisepolluter

That was weird - swapped V4 (stock fender - Christ knows how long that's been in there) with a spare JJ I had lying around. Definite improvement with reverb and tremolo until sudden very loud horrible buzzy noise (not my playing). Amp volume was barely on 1. 

I'm pretty certain I didn't damage the valves or sockets while doing the swap. I am puzzled. The JJ might have been a knackered one swapped out of something else ages ago that I forgot to chuck out, I suppose. 

I switched it off straight away anyway, and replaced the original V4 for now. If all the the preamp valves are stock, I really ought to order a new set anyway.  

noisepolluter

Problem solved - found a virtually unused Groove Tubes 12AX7 that I pulled out of another amp shortly after I bought it. It's removed the reverb crackle entirely, and significantly reduced the background noise. Also seems to have improved the sense of depth, but I would' t swear to it. It does get a bit ringy and microphonic past 7, but I put this down to being a cheap 'n' cheerful stock valve - at least it's functional. I hardly ever have the reverb above 4 anyway.

I'll be ordering some nicer preamp valves in the meantime - will probably go for some JJ's unless anyone has any strong recommendations under £10 or so? I don't want to get into gold pin/NOS territory.

ICBM

I would avoid JJ preamp valves. They sound dreadful in my opinion - an odd combination of harsh and muddy at the same time. I've also found them less than reliable, as you seem to have done too. (Their power valves are OK though.)

Don't cheap out on valves. You've bought a good amp, in my opinion it's stupid to buy the cheapest valves you can get for it. Good valves not only sound better but last longer, so cheap ones are usually a false economy too.

Richardj

I had a very interesting moment earlier with my newly acquired DRRI. I have my pedal board set up with an A/B so I can have a pure signal into the rev/vib channel and effects into the normal channel. I set my Hardwire Supernatural to the spring setting and I cannot actually tell the difference between it and the inbuilt classic Fender spring reverb.  This is how good is the Hardwire/Lexicon reverbs are!

jpfamps

Richardj said:

I had a very interesting moment earlier with my newly acquired DRRI. I have my pedal board set up with an A/B so I can have a pure signal into the rev/vib channel and effects into the normal channel. I set my Hardwire Supernatural to the spring setting and I cannot actually tell the difference between it and the inbuilt classic Fender spring reverb.  This is how good is the Hardwire/Lexicon reverbs are!

We found this comparing a DRRI with the Wampler Spring Reverb pedal, which incidentally uses the Belton brick digital reverb unit.

I bought one of the bricks a year or so ago to have a go with, but haven't got around to it yet.............

ICBM

Apart from the fantastic noise you get when you bump a spring reverb unit when it's on - and possibly the fact that they do feed back a bit, which might enhance the effect - I really think the days of spring reverb are numbered, and probably rightly. They're mechanically fragile - newer Accutronics ones in particular are poorly designed and inherently prone to failing - pick up interference, and take up a fair amount of space.

I'd certainly far rather have a digital than any spring reverb short of a full valve-driven type using a top-quality (ie not Accutronics, unless modified) spring, now.

noisepolluter

Richardj said:

I had a very interesting moment earlier with my newly acquired DRRI. I have my pedal board set up with an A/B so I can have a pure signal into the rev/vib channel and effects into the normal channel. I set my Hardwire Supernatural to the spring setting and I cannot actually tell the difference between it and the inbuilt classic Fender spring reverb.  This is how good is the Hardwire/Lexicon reverbs are!

I have a hardwire reverb (bog standard, not supernatural) - I agree the spring sound is astonishingly close. I think the actual spring reverb has a sort of grittiness to it whereas the pedal spring sound is cleaner, but there's very little in it.

martinw

ICBM said:

I would avoid JJ preamp valves. They sound dreadful in my opinion - an odd combination of harsh and muddy at the same time. I've also found them less than reliable, as you seem to have done too.

I don't agree. Never had any problems with reliability on the many hundreds I've used, and I like the way they sound. There's an amp I built in the classifieds at the moment where the customer replaced the JJs because he thought they were "too bright"!

ICBM

martinw said:

ICBM said:

I would avoid JJ preamp valves. They sound dreadful in my opinion - an odd combination of harsh and muddy at the same time. I've also found them less than reliable, as you seem to have done too.

I don't agree. Never had any problems with reliability on the many hundreds I've used, and I like the way they sound. There's an amp I built in the classifieds at the moment where the customer replaced the JJs because he thought they were "too bright"!

It is odd. I've come across quite a few failures of them, particularly in cathode follower positions, and some that just went noisy or intermittent in gain or tone.

I think I understand the 'too bright' comment - it's the same as some people saying that V30s are a 'bright' speaker - to me they aren't, they're a dark speaker with very little true top-end, the "brightness" is that upper-mid spike they have which can sound very good with some amps but harsh with others. I find JJ 12AX7s are sort of the 'V30 of valves' .

This demo is a very good illustration - it's really for the Retrovalves but one of the comparison valves is a JJ.

I was sure the first one was a JJ straight away, even before I heard the others - there's a distinctive mud to the sound. The Tung-Sol and the EH are much brighter and clearer, and also more natural and open-sounding to me.

martinw

I can hear that, but don't dislike it, although I have to say that wouldn't be the distortion sound I'd shoot for. Possibly with differing set-ups, other factors come into play. I like the warmth they bring, and think of some other valves as being thin rather than clear.

I have been using them virtually exclusively for the last7-8 years in my own amps and all the repairs I do, and haven't found an amp that I don't like them in. I think all the clips on my YouTube channel were recorded with them.

[Shrugs] Ah well, it's all subjective at the end of the day.