Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 4, 2009 21:35:45 GMT
Steverino
I don't have your technical knowledge!1
But it seems to me that for a PA transistors rule; for clean acoustic amplification, like the Marshall acoustic amp, transistors also rule. They are the best things to use because they tend to last a very long time and are predictable.
But valves are great in a rock or blues genre because they do change the sound if you add gain or crank up the volume. They change the sound to be more of what we want. Isn't that why we bother with valves (tubes for those on the west of the Atlantic!).
Interestingly I tried a non Fender single knob 6w valve amp and didn't like it: the valve effect only came on at full volume. The advantage of the Vibro Champ was that with my non reso guitar that I used at the time I could get a bit of 'blues' sound onto the recordings, and at very low volume so as not to disturb the neighbours!
Let the debate roll on.
|
|
|
Post by jackstrat on Jan 16, 2009 23:08:14 GMT
Hmmmm...
I like my new Champ 600...great sound etc...BUT....
Took it to my mate's studio tonight to do some test recordings and I must say I came back somewhat disappointed...the electrical hum that I had taken little notice of before just proved to be too loud and was picked up goodo by the mic...not good.
Anyone else had this problem? Any clues on how to sort it? Andys, I think you mentioned a forum that offered some advice, and I looked, but I didn't see anything...
I'd really appreciate any help guys...ta
Niall
|
|
|
Post by Michael Messer on Jan 17, 2009 11:02:51 GMT
Hi Niall, Having not heard the electrical hum on your amp I can only comment on valve (tube) amps in general. They do often develop a hum which obviously gets louder as the volume is turned up. I have three valve amps of which two are silent and one has a hum. With valve guitar amps a slight hum is not really a problem in the studio unless you are looking for a very clean recorded sound. I have been recording with valve amps for years and I just don't worry about the hum. When we recorded 'Second Mind' and the 'Play The Blues' CDs it was a production decision to keep all amp hum and tape hiss on the recordings. I am surprized that a new Fender amp has a circuit hum. Valves ARE tempromental. A new valve will either start to malfunction in the first month or so of use, or just go on for years. But it is in the first month or so of use that valves are at their most fragile. Another cause for hum is a bad soldering or a weak capacitor or something....but in a brand new amp that shouldn't happen. I am VERY careful with my valve equipment - I always carry it myself, allow it to cool before moving it, in the car I sit it on a cushion to absorb vibrations, I allow it to warm up for five minutes before I use it - and I ALWAYS carry a spare set of valves. Some people remove the valves after every gig and keep them in a padded-foam camera case. I am not sure that is necesarry, but valves are fragile. NEVER turn them on and off quickly - this can and probably will destroy a valve. If you turn your amp on wait five minutes before turning it off. If you want to turn it on again....wait five minutes and turn it on. But flicking the power switch on...off....on....off....WILL destroy the valves. A possibility with your amp is that the valves have been damaged in transit before you got it. My advice is to do what I suggested at the beginning of this thread, but now for a different reason. Get a high quality set of valves and go from there. I don't know what valves Fender use, but I am fairly certain that no matter what brand name is printed on them, that they are cheap Chinese or Russian and stamped with Fender's logo. The guy at Watford Valves is very helpful and will be able to advise you about your amp hum. Watford Valves Tel: +44 (0)1923 893270 Email: sales@watfordvalves.com THIS IS INTERESTING: I just found this on the Watford Valves website> www.watfordvalves.com/product_detail.asp?id=1916Let me know how you get on Shine On Michael
|
|
|
Post by jackstrat on Jan 17, 2009 12:32:07 GMT
Hiya Michael,
Many thanks for the quick reply!
This hum (as opposed to a 'hiss') is a constant 'note' that becomes audible once the unit heats after the first say 10-20 seconds. I feel like putting a tuner on the amp and finding out exactly what note it is!!
It's audible and stays at the same level regardless of the volume setting and whether or not there's a guitar connected, and it's nothing like that earthing hum/crackle that comes and goes when you touch the strings etc. (that's happening also...but that's a given!) I've a big 4x10 60w Deville that's never given anything other than the usual valve 'hiss'. This is a different issue entirely I reckon.
Initially I didn't pay too much notice as I was inclined to blame the dimmer switches in our new house, but when I realised that it was happening regardless of same and when I heard how intrusive it was when picked up on mic in the studio I started to become quite concerned.
I've emailed the customer services at the company who supplied the unit and I've also contacted the guy at Watford Valves on your recommendation.
I'll keep you posted and again thanks for the info etc.
Regards, Niall
|
|
|
Post by Michael Messer on Jan 17, 2009 13:06:19 GMT
Hi Niall,
It sounds to me like a valve is on its way out. If it was a vintage amp, a problem like that can be a capacitor and can cause serious damage. But Fender produces thousands of these amps, so it is my guess that their circuitry and assembly is spot on.
As I said previously - valves are fragile.
You can often tell if a valve is on the way out by switching the amp on and tapping the valves gently with your fingernail. If they are pinging or have become microphonic, they need replacing. You will probably have to take the back off to do this test. Sometimes they are not microphonic, but are still on the way out. It can be hard to tell without replacing them.
If you want to talk to an amp expert I can PM you the phone number of the guy that looks after my amps. I am sure a five minute phone call to John would be helpful for you.
Let me know how you get on.
Shine On Michael.
|
|
|
Post by jackstrat on Jan 17, 2009 13:37:23 GMT
Hello again Michael,
Interesting, very interesting...
I'll resist troubling your mate for the moment (although thanks for the most kind offer...super!), but I suppose it'd be no harm to wait till the start of the week for a reply from the company that supplied it...see what they come up with. If they're willing to accept that it's a fault (not just some minor adjustment) and they offer to sort it for me then I'll go with that solution. The problem is they're in Germany and I'm in Ireland so I could do without all that transport hassle...aaagghh!!
I will however try what you have suggested re the valves if I can get at them without opening it (I'd better remember my guarantee!!) and if I come up with anything I'll let you know.
Many thanks and regards, Niall
|
|
|
Post by andys on Jan 17, 2009 15:41:12 GMT
Hmmmm... I like my new Champ 600...great sound etc...BUT.... Took it to my mate's studio tonight to do some test recordings and I must say I came back somewhat disappointed...the electrical hum that I had taken little notice of before just proved to be too loud and was picked up goodo by the mic...not good. Anyone else had this problem? Any clues on how to sort it? Andys, I think you mentioned a forum that offered some advice, and I looked, but I didn't see anything... I'd really appreciate any help guys...ta Niall The forum is on www.tdpri.com. Go to the guitar forum, and then to Amp Central Station. Theres stuff on there about the Champion 600. I have to say that I originally looked into getting a 600, but at the time a lot of the talk was about problems with hum. There are mods you can do to curb this. The early Valve Jnrs had hum issues, but I learned that the later ones had it sorted. So thats why I plumped for the Epiphone, as not only was it quieter, but it had a bigger speaker, and there was loads on the Epiphone forum about modding them. I have heard that the new Valve Jnr is wonderful, as Epiphone have basically put all the mods that folk have been doing, into the latest version of the amp, and by all accounts the new Valve Jnrs are great amps for the money. My Epi amp, is great, but very loud. I have started running the 4ohm output into a bigger 16 ohm cabinet, and getting a good sound out of it, at lower volumes.
|
|
|
Post by Michael Messer on Jan 18, 2009 12:08:38 GMT
Hi Niall,
Andy is correct. There are problems with these amps.
I have heard through the grapevine that as many as one in every four new Fender amps are having to go back to Fender to be repaired. Fender amps are no longer manufactured using solder. They are 'dry jointed'.
I can tell you that once repaired or replaced by Fender, that it is well worth doing the mods I mentioned earlier in this thread - a Jensen speaker and proper high quality valves/tubes will really make your amp sound great. Good 'old stock' valves, either US or British made, are very different to what Fender use. So is a Jensen speaker.
Can anyone tell me what DRY JOINTING actually is? Apparently solder is now considered dangerous for the people using it and that is why they now Dry Joint their amps.
Shine On Michael.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jan 18, 2009 12:55:30 GMT
Solder needs flux to clean the metal that is being joined together. The flux for soft solder is noxious, when I was working as a locomotive builder soldering the bodywork together I ended up with a chronic sinus infection that took months to go and if I ever solder now I use a proper air filter.
I assume dry jointing is using very very exact fits of male/female components to connect the parts. A taper fit would do this but the smaller the taper the more likely it is to work loose. Loose connection = no working amp.
When I can I will re-speaker and re-valve my Vibro Champ.
Hope the above makes sence.
|
|
|
Post by andys on Jan 18, 2009 13:28:54 GMT
Theres some great little valve amps coming onto the market at the moment. I have heard good things about the Blackheart amps, which have switchable outputs, and they also do something called the Killer Ant wich is a 1/2 watt thing that can be put through a big cab, to give valve overdrive at bedroom volumes. The Mods I have done to my Valve Junior were all obtained off the Epiphone Forum. I opened up the input stage, opened up the stage between the pre-amp and power valve, put in a new Hammond Transformer, and put JJ valves in. Another place to get amp valves/spares is www.bluebellaudio.com. I loved modding this amp, I am getting the itch to do some more amp work again. My next amp though is going to be one of the kits at www.ampmaker.com. The little SE-5a amp looks fantastic to me. Ampmaker have just started trading again, so I'm saving my pennies for one of their kits.
|
|
|
Post by jackstrat on Jan 20, 2009 21:53:46 GMT
Howdy Lads,
Well here's the update... I got an email reply from the company that supplied the amp, and true to form they are providing marvellous service. They're taking it back (it's being collected by a courier tomorrow - all organised and paid for by the company) and all going according to plan, they're going to replace it with an Epiphone Valve Junior (at my request). I've opted for the Valve Junior afterall because when I compile all the advice and info (thanks guys - really appreciate the time and help), it just seems the EVJ is a more reliable option. To be honest, I don't really see the point in buying a NEW amp and then immediately changing all the significant bits (speaker, valves etc.). I'd rather have one that does 'exactly what it says on the tin'!! I would love to have the Champ 600, but if I feel that I can't trust it, or that it's gonna be expensive in the long term, then I'm not interested. So, here's hoping that all works out sooner than later... I'll keep you posted, and thanks again for the discussion - brilliant!
Niall
|
|
|
Post by andys on Jan 21, 2009 20:01:29 GMT
I love these little amps, but folk have to remember that they are cheap valve amps, and as such they do have their limitations. The new Valve Juniors come with decent valves, I think they put Electro Harmonix ones in now. Also although the Valve Junior has a nice 8" Weber speaker in them (or a very good equivalent), they do sound much better through bigger speakers. The combo is loud enough for small gigs, though dont expect clean tone at that volume, but putting these amps through a bigger guitar cabinet, really opens them up. A Valve Jnr through a 4 x 12" is a wonderful thing, and brings a smile to your face. The new combo as well as the head, now come with 4,8 and 16ohm outputs, so you can put them into most cabs. Mine only has a 4ohm one, but it is an older version. Having said that, they are not boutique amps, and cannot be compared to them. They are though, cheap amps, which are easy to tweak, mod and customise. Above all they are a lot of fun for not much money.
|
|
|
Post by Michael Messer on Jan 22, 2009 0:05:23 GMT
Hi Niall - It sounds like you have it sorted!
Shine On Michael.
|
|
|
Post by jackstrat on Jan 22, 2009 9:19:05 GMT
Hopefully...hopefully!!
I know it's a lot of bother over such small cheap amps, but I am convinced of the potential of these little units nevertheless – be it the Champ (a good one that is!!) or the EpiVJ – the combination of reasonable tone, good price and portability makes them very attractive...certainly as a second/alternative amp.
So, I'll soldier on and hope that all works out ok! (The courier collected yesterday)
I'll keep you posted...and thanks again!
Niall
|
|
|
Post by andys on Jan 22, 2009 12:41:52 GMT
Another amp to check out that has just appeared is the new Vox AC4. All valve, with a 10" speaker, and a power attenuator as well. They look cute as well. Bit more expensive, but they will come down in price.
|
|