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Zeuhl

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  1. Yeah it's heavy, it's great: it doubles as gym equipment too!
  2. Sorry guys, had forgotten about that one. No I never sold it, I didn't try very hard to be honest. So still up for grabs if someone is interested as I'm not using it anymore. Thx
  3. Sorry guys, had forgotten about that one. No I never sold it, I didn't try very hard to be honest. So still up for grabs if someone is interested as I'm not using it anymore. Thx
  4. No one, really? Too mighty for people to handle maybe lol
  5. Get yourself the ultimate bass head, the rolls royce of amps. Very rare and sought after Head, 400w of raw power all tubes (8x 6550 and 3x 12Ax), 4 and 8 Ohm selectable, 2 channels (clean and crunch) which can be blended together. This thing is a beast and you are unlikely to find any better in terms of sound and power. A true marvel when played on a large cab. Very loud and very heavy (100lbs!). Never abused, in great condition. Comes with its own custom made touring case on wheels. Based in Scotland (cab on pics not included).
  6. I recently bought Laurence's beloved Classic 400. I must say I'm delighted with the purchase. Laurence is a really nice guy who knows a great deal about amps, basses, effects, mixing etc. Communication was perfect. He's also kindly found me a cheaper alternative for shipment which was great given the weight of this head! The Classic seems to hold a lot of sentimental value, so it was also good to feel trusted and considered as a reliable new owner. Laurence surely knows that I won't easily get rid of this one and that his amp will be well looked after! Cheers mate and thanks for the great deal!
  7. I just bought a bass from Ben. Good communication and a nice guy. Everything went very well (payment, shipment). Very happy with the deal, would definitely recommand him.
  8. [quote name='Musky' post='1346303' date='Aug 20 2011, 01:25 PM']Shame. Have you started working on that dummy load then? [/quote] Lol. No, I have ditched this idea (I have many crazy ones! ) and I am looking for another head now. I would quite like a Mesa 400+ actually (it has a 8 Ohm output) but they seem a bit hard to find... I'll keep on looking.
  9. [quote name='Musky' post='1338442' date='Aug 13 2011, 09:15 AM']It only applies to valve output stages. Amps with only a valve preamp are not affected. It might be worth having a word with Marshall - it's possible the output transformer might have an 8 ohm tap which isn't used. Unlikely, but you never know. [/quote] Hey Musky, Just for your information, I have asked Marshall and there is no 8 Ohm tap on the output transformer of the VBA400; which makes sense, otherwise they would probably have put a 8 Ohm output to the cabs too.
  10. [quote name='Musky' post='1338512' date='Aug 13 2011, 10:28 AM']It would work, but you'd be dissipating plenty wattage in the form of heat. A lot of it - the spec sheet gives the max temperature as 358 C. Some sort of fan might be in order. Or just get a second 8 ohm cab.[/quote] That's right: big heat sink, thermal compound, casing, fan, psu for the fan... it might end up being cheaper buying another cab... Would be a funny project though: an amp ideal for cold long winters. Thanks for all the help anyway, Musky.
  11. [quote name='Musky' post='1338442' date='Aug 13 2011, 09:15 AM']It only applies to valve output stages. Amps with only a valve preamp are not affected. It might be worth having a word with Marshall - it's possible the output transformer might have an 8 ohm tap which isn't used. Unlikely, but you never know. [/quote] Thanks, I will try to contact them. Shame that electric diagrams of amps are not easily accessible... Now, it might sound stupid but what if I connect a dump load in parallel with the cab, I mean a big chunky resistor such as this one: 500W, 10 Ohm: [url="http://uk.rs-online.com/web/p/high-power/7013943/"]http://uk.rs-online.com/web/p/high-power/7013943/[/url] It would bring down the impedance to 4.5 Ohms. Now, it's a purely resistive load so I'm not sure what the overall effect of the RL circuit would be ... Don't hesitate to tell me if I'm being an eejit or if doesn't sound too bad an idea.
  12. [quote name='Musky' post='1338423' date='Aug 13 2011, 08:45 AM']You should definitely NOT run an amp with a valve output stage at a higher impedance than intended. With transistor amps you're fine to run a cab with with a higher impedance than the amp's minimum load (typically 4 ohms). All that happens is that the amp will output a lower wattage into the cab. Valves are very different - they have a very high output impedance (thousands of ohms), and need an output transformer to match them to the comparatively low impedance of a speaker. They also run very hot and at high voltages. Running them into a higher impedance than intended will mean the valves will produce a higher voltage to drive the load and get even hotter. Not good for valves at all. If the voltage gets too high you can expect arcing to occur anywhere along the high voltage path. Result? Destroyed valves/valve bases/output transformer. The worst case scenario would be running the amp with no load connected (or a broken speaker lead) which presents the amp with an infinite load. The magic smoke will very quickly appear. Depending on the tolerances of the valves and design of the amp you might get away with running the amp on the 4 ohm tap into an 8 ohm load for a while, but the valves will run hotter and have a shorter lifespan. And as I'm sure you know, revalving a big amp can be an expensive business.[/quote] Thanks for the detailed explanations, Musky. Is it the same for hybrid valve/transistor heads or are their valves totaly isolated from the output ? I suppose I might have to get another 8 Ohm cab and wire the two in parallel if I want to stick to the VBA400... or get another head (or a low impedance cab...)
  13. Hi guys, I own an Ampeg SVT-15E cab which is rated at 8 ohms. Originally, I was going to get an SVT head but actually, I quite fancy the Marshall VBA400 which is all tube and has selectable output of 1, 2 or 4 Ohms. I know it's probably a question which has been asked a thousand times and I do know that, in theory, I should be ok running the 8 Ohms cab with this head; however people seem more cautious about impedance mismatch when it comes to all-tube heads. Do you think I would be ok running my SVT15 with the all-tube VBA400 ? If not, has someone got an idea why ? Is it because of resonance issues due to the inductive load, or something else... ? Thanks
  14. Just bought a SVT 15E from elephantstone and I'm very happy with the purchase. He has been really good at answering to all my questions about the past history of the cab and he's also a very nice chap who warmely welcomed me into his home. As mentioned in his advert, the cab was in immaculate condition (it really looked like a bran-new one !). Thanks for the deal, mate.
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