VTypeV4

[quote name='Mikey R' timestamp='1356547165' post='1911065'] Cheers V4! Youve got me hatching a plan... [/quote] A Beavis clone? I'd love to see that!

I haven't got all the numbers but from the sheet the guy did when he modified beavis.. ~575 volts on the plates ~49 ma current draw This apparently was the starting point after he'd modified the bias circuit but finally ended up setting it a bit hotter as it sounded sweeter and made a tiny touch more power.. As for what the load the transformer presents to the valves, I have no idea. The original design was for EL34 valves if that helps with a guestimate. Inconveniently the secondary only sees 4 or 16 ohms which is a bit of a pain when wanting to try other cabs but if it ever fries, I'll get it re-wound for 4-8-16 ohms..

Gotta love those glowing bottles man!

[quote name='Mr. Foxen' timestamp='1355712225' post='1901766'] What a valve does depends entirely on the circuit you put it in. 'Tone profiles' of valves can only apply to specific circuits since the same valve in a different circuit will do different things. [/quote] +1 to this.. Which is why I put the reference amplifier at the end of each review and where I've used the same in a number of amps, it's a general overview.

[b][size=4]Tube reference[/size][/b][size=2].[/size] [size=3]I thought i'd do a bit of a reference on my personal experiences of various output valves/tubes i've used over the years. [b]Tung Sol re-issue 6550[/b]. I have used this valve in a number of applications over the years and have to say, it's a really good valve. I've never had one fail and still have the original quad i bought in 2004. I purchased them for use in my Trace Elliot V4 as an alternative to the Ruby Tubes KT88s it came with. These are a warm but tight sounding valve offering plenty of clean headroom before breakup with a really wide band of 'not quite breaking up but still compressing' thing going on. They really grind when they're thrashed offering a very aggressive edge. The bottom end is very tight although not as pronounced as other types I've used. In the middle is where this valve really shines, it's smooth and punchy without being unpleasant or obtrusive, just gives everything great body and definition. High frequencies are handled without drama being smooth and natural until driven hard when they get gnarly but in a good way. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Beavis 50 and Trace Elliot V4. 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Most certainly yes. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] No, 8 valves still intact, 6 still in service, 2 spares. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] Great definition from a high power valve where detail and dynamics are paramount. The best 6550 I've used. Great valve. 　 [b]Shuguang KT88 98.[/b] I believe this is the standard issue Shuguang KT88 valve on which even the super posh expensive 50th aniversary models are based. The expensive variants have detail changes such as the glass, gold pins etc. I have used two variants of this valve, the first being a Ruby Tubes branded quad and later a standard Shuguang quad purchased on ebay. Both were sonically identical in their delivery was generally very good. I did however have a vacuum failure in one of the Ruby Tubes quad which was a shame and in the Shuguang quad, one was duff out of the box but the supplier changed the valve without issue. This valve has a very warm sound being very smooth right through the range which makes it great for all applications. This valve seems to go 'lower' than the other 6550/KT88 variants but doesn't seem to offer the same control over the the real low stuff when worked hard. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Trace Elliot V4. 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Most certainly yes. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] Yes, one vacuum failure and another duff out of the box. Still have 2 spares. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] Lovey and warm valve giving everything a nice rounded bottom end. Excellent value tube. 　 [b]Electro Harmonix KT88[/b]. Not quite sure but I think these are made in Russia and re-branded. I have a matched sextet of these residing in my Ashton amplifier and are the best KT88 variant model I've used. They are a very loud and clean valve offering masses of clean headroom with an excellent dynamic range. When pushed, the valves don't so much distort as just compress which makes them great for bass guitar. The EHX valve offers a similar amount of bottom end to the Shuguang valve but retains control over it even at high output levels. Midrange is smooth and detailed but not pronounced and top end has plenty of sparkle with no graininess or harsh characteristics. I expect a set in a hifi amplifier would yield great results in both terms of power and detail. I've had no failures yet, they seem to be a really good valve. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Ashton BV300H and Trace Elliot V4. 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Most certainly yes. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] No, all six still in service. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] The best sounding KT88 I've used. Highly recommended. 　 [b]Shuguang/Ruby EL34B[/b]. I understand these were the first of the larger bottle 'heavy duty' EL34 valve. They came up cheap in a local music shop so I had to have them even though I didn't need them at the time. The pair are the Ruby Tubes branded variant. Having used them in two applications, they have performed very well in both. I tried them in Beavis for a while in place of the JJ EL34s that were in at the time but when it was re-configured to use 6550s, they went into my Linear L30 to replace the tired Mullard EL34s. In Beavis they weren't quite as smooth as the JJs, giving a noticeable crest at around 3kHz but did offer more clean headroom, 6 of one, half a dozen of the other I guess. They're better in the Linear helping its definition without coming across too harsh or unpleasant. Bottom end is natural and smooth with a pleasant roll off making for a 'normal' bass response but its in the upper mid-range where this valve will be liked or lumped. From 2k5 through to about 4khz, the valve has a pomenant character which can make it sound a touch brittle. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Beavis 50 and Linear L30 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Probably although I'd like to compare the to JJ KT77 which may have the best of both worlds. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] No, both still in service. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] High power EL34 great for giving definition but can be a touch harsh if pushed. 　 [b]Sovtek EL34G.[/b] Not a bad valve but I think the Sovtek company have stepped their game up since these were in production. I used them for a number of years in Beavis as these were the brand new valves it was built with back in 1996. I think the later version of the 'G' was the WXT which I also used in the same amp for a short time. The bottom end on this valve is quite normal, not bad but nothing particularly exceptional to speak of. Midrange body and definition is more than adequate, the valve offers the typical 'bite' expected from an EL34 which can get quite crunchy when pushed hard. This does however mask the top end just a little above about 6 khz when pushed hard. It also clipped earlier than other variants I've used which whilst not ideal for hifi, is great for guitar work. I later gave these valves to a friend for use in his Marshall amplifier. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Beavis 50 and Marshall JCM800 combo 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Unlikely as I believe better valves are now in production for both power and sound considerations. [i]Has one failed[/i][font=Times New Roman]?[/font] No, both still in service. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] An outdated valve no longer in production but was rugged, reliable and good in guitar amps. 　 [b]JJ EL34. [/b] A personal favourite in terms of sound within the EL34 family. In every application I used these in, they worked brilliantly and without drama. The valve looks to be well built big plates, getters in the top and a solidly mounted base. This is a very smooth sounding tube offering great dynamics and not that brittle edge that EL34s can be guilty of when worked hard. They don't quite have the same headroom offered by the EL34B but the overall character is somewhat smoother than any other EL34 I've used. It has no particular frequency band where its promenant or shy which make it great for hifi work although in instrument amplifiers, it offers plenty of warmth and body. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Beavis 50, Sound City 120 and Musicman HD65 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] Probably although I'd like to compare the to JJ KT77 which may offer more power with the same tonal character. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] No, both still in service. 　 [i]Overall impression[/i][font=Times New Roman]?[/font] Lovely EL34, my favourite. Great in all applications. 　 [b]Svetlana EL34.[/b] I have no idea what these sound like as I never managed to get two working at the same time. I tried two pairs of these, both had a duff valve in each pair, both exhibiting spitting and buzzing through the speaker whilst lightning sparked inside the glass. I had my money back and put the Sovteks back in. 　 [i]Reference Amplifiers[/i][font=Times New Roman]?[/font] Beavis 50 　 [i]Would I use this Valve again[/i][font=Times New Roman]?[/font] No, they never worked. 　 [i]Has one failed[/i][font=Times New Roman]?[/font] Yes two in two pairs 　 [i]Overall impression[/i][font=Times New Roman]?[/font] Bad valves. I know it was probably bad luck but two consecutive bad valves put me off. 　 I've used other valves but not extensivley enough to pass comment on and frankly, I've probably bored everyone to death already. Cheers, Matt. Hope this helps.　 　 　 　[/size]

12 x 6L6 are mighty damn pricy! It's one of the reasons I've never had a 400+ although I'd certainly have it's smaller cousin, a buster head. I'd explore all other avenues before making the plunge. All the advice on here has been great so far.

Truth is, I'm not sure.. I assume it was an adjustable bias model as it was a re-issue model bought from Doncaster. I think it had svetlana KT88s. I've never used these in anything so I'm not sure of their character traits. Maybe it would have been better with EHX or Shuguangs..? My 100w model was adjustable but it wasn't so much a tonal issue with this one, it was simply a lack of stones.. I'd love to find one that I liked as I think they're the nuts to look at.

I did read something about the pots and jacks being quite poor and prone to failure.. I haven't seen one in the flesh for years! Was the RedBear brand a similar thing?

Anyone remember these? I was trawling through some valve stuff on eBay and noticed a couple of the Sovtek 'Big Muff' pedals which got me to thinking about the Sovtek amps that were about in mid-late '90s. I think there was the MIG 50 which was a Bassman circuit and the MIG 60 which was Marshall 800 series circuit. I seem to remember there being a 'B' variant which was for bass and the Bassov series which may have been 100w models? I can't quite remember!? Just wondered if anyone had any experience of them or indeed still uses one today?

I have a difficult relationship with Hiwatt stuff.. I love the way it looks with it's timeless charm and excellent build quality both inside and out. Perfect neat lines from A - B, top quality componentry etc. I've heard great sounds come out of both EL34 powered 100 watters and the bigger '88 loaded 200w models but... I just can't get along with any of them. I had an '80s 100w which was OK, it sounded nice enough but it never seemed right, my Linear L30 would maul it in terms of power let alone Beavis (50w at the time also EL34 loaded) so didn't keep it all that long. I tried a new set of Harma EL34s but it was still flat. Later I borrowed a friends' 200w and that was just not to my taste. It had this hard metalic character (1 - 4 kHz) that I simply couldn't get away from irrespective of what I did with it. There was plenty of power on tap but they're just not to my taste..

Not the prettiest but perfectly functional and not even too noisy.. [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/DSC00188.jpg[/IMG] The Chassis.. [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/BeavisChassis.jpg[/IMG] Cased up and good to go.. [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/BeavisClean.jpg[/IMG] I know some of you have seen this on the other thread but I considered it would keep Mr F happy!

That thing looks stunning! It even makes my Leak ST20 look a bit budget!

Sorry for the delay, my laptop has gone mad so I'm on my big computer for a bit.. Beavis isn't one of John Chambers creations, if he was I'm sure the build would have been much tidier! Johns amps are built much to the same standards of the '70s Hiwatt amps, top drawer indeed. The original amp was a Linear L50 (pictured) but it was rebuilt by my stepdad as a beefed up Marshall circuit back in about '96 whilst he was on an electronics course. Linear L50 (without cage): [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/LinearBeavis.jpg[/IMG] Beavis guts: [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/DSC00188.jpg[/IMG] Here is a gut shot underneath not very tidy but still easy enough to fix and not excessively noisy surprisingly enough. Inspite of the slightly messy interior, everything works just fine with the amp making 62 watts just before clip. And they're good 'full fat' watts at that! I do however think the o0utput transformer must be marginal!! A lovely sounding amp! It's been really reliable too, used as a back up when the various Trace amps I've had over the years decided not to play ball. I've used it since about '97 and can report only two breakdowns to date and not to jinx it but none since 6550 conversion back in '08.

I think you've already talked yourself into 1 x 12".. I haven't tried the cabs you mentioned but I tried an EBS rig about 10 years ago that had the older style 2 x 10" and it was storming. A really great bit of kit. I've also owned Trace Elliot 2103H and Ashdown MAG 210T cabs although I expect you're looking to more modern and lightweight items?

Does anyone have any experience or own one of John Chambers (or anyone elses for that matter) 200w (4x) EL34 amplifiers? I always think of EL34s as a valve that begins distort early which (in most cases) isn't great for bass. My own experience and what I percieve my bass 'should' sound like shows I prefer a cleaner valve such as 6550 / KT88. I'm not saying they don't get loud, a 50w Marshall on the boil seems somewhat massive not to mention the Sound City Energizer 120 (6 x EL34) I had. That thing was capable of hurting speakers but again with plenty of distortion. EL34 amps always seem to begin to break up then go loud whereas 6550 / KT88 go loud then break up. And I know this isn't strictly true because it doesn't work like that but it's always how I've percieved it.. Beavis used to run EL34s and was marginal at best but with the appropriate mods (bias etc) now runs a pair of R/I Tung Sol 6550s and is capable of keeping up with most situations. I don't play in any rock groups. [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/BeavisChassis.jpg[/IMG] [IMG]http://i778.photobucket.com/albums/yy70/VTypeV4/BeavisClean.jpg[/IMG] And the Ashton doesn't really need a mention because it's beyond any doubt the cleanest valve amp I've ever played. I'm rambling a bit here but what I'm really trying to get at is [b][i]'how much of a character change do the EL34s go through when worked much harder in this way' [/i][/b]? Are they still clearly crunchy and biting like in more conventional circuits or do they take on something altogether different?

I'm surprised the old 200w Buster head didn't do better -inspite of it's price- as it was a great bit of kit. Simple enough to keep the 'plug n play' types happy an enough fiddle to keep the 'tweak freaks' in shape. I remember having a go of one in Liverpool (or was it Manchester?) back in about 99/00 and thinking it was a really great amp. I have a feeling it was the same day I tried a 400+ too although i was much less sold on that than the buster. I'm not really a massive fan on the look of those new heads but if they sound as well as the Buster, then they should be a great product..

[url="http://soundcloud.com/vtypev4"]http://soundcloud.com/vtypev4[/url] My new (Coastal) track and some other older stuff by me..

Thought i'd stick it on anyways.. Cheers for the info, I assume its the old style G12H judging by it's date which makes it a 30 watter?

[quote name='Bill Fitzmaurice' timestamp='1352947835' post='1869755'] Too much work. Just go to the Peavey site, get the T/S specs, find a similar driver. Similar, but not the same, as the 2.8mm xmax of the 1502 is marginal at best. The CA 154 is not compatable, and xmax is no better. As for replacing the basket, the 1505 is a much better choice, specs are compatable, but[i][b] I don't know if the 1505 basket will work with the 1502 magnet[/b][/i]. It's worth checking it out. [/quote] Every BW I've come accross has had the same magnet so it'll probably be fine..

In all fairness BWs are a really good drive unit in terms of bang-per-buck. They are very hardy both mechanically and electrically as long as they're not [i]seriously[/i] abused for long periods. I have used them mainly in PA applications over the years including a period where I needed an 18" for a sub that had died just as a stop-gap. It had a big Crown 3600VZ up it for a while and even when it was replaced, it was still going strong inspite of the 1500w or so that it would occasionally see right down to 32Hz!. It even outlasted the 800w Eminence Omega in the partner sub! I smashed those up with alarming regularity so bit the bullet and got Precision Devices 1000w units instead. 5 years on and they're still doing the business. The only problem is that the replacement baskets are quite expensive for BWs, much more than they used to be just a few years back but are still cheaper than trying to replace with an equivilant unit. To the OP, I would personally stick with the BW even if the existing one is fried. Replacing like-for-like will guarantee a continued performance level without cabinet mods and as you've already seen with other posts, other drivers are unlikely satisfy. Do all the checks as others have posted then at least you'll know where you stand.

Before you discard or replace the BW, double check the tinsel leads that run from the connector panel on the speaker itself. They run into the yellow suspension support from the black panel and should be clearly visible. I say to check they're in good order as I've fixed many a dead or bad sounding BW simply by re-soldering broken or nearly snapped ones bringing many more years of faithful service from the drive unit. I'm not saying this a guaranteed fix but double check yours, it might be a simple (and in-expensive) repair.

Very insteresting indeed..

Still got it guys.. Gonna leave it available for another week or so but failing that, It'll go for scrap..