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  #1  
Old 31st December 2005, 01:18 PM
andrew ivimey's Avatar
andrew ivimey andrew ivimey is offline
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Default Loftin White

How's this project going? (Simon, Shadow and David)

Having built my own up and up and am at present enjoying the old RCA twinplates (But isn't it odd how any 2A3 sounds great?) ... I have at last acquired a blackgate wkz for the power supply.

Already I am using Elna Cerafine so this WKZ better bleedin' be brilliant!

And that, for me is the final 'mod' with this amp.

Most effective changes were the amorphous silver Txs and mullard Ecc83s.

This is a great amplifier!
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  #2  
Old 31st December 2005, 01:40 PM
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david counter david counter is offline
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Default Re: Loftin White

hi Andrew,
mine's developed into a bit of a saga, I'm more or less there now though, wonderful looking obligato 22uf oil filled caps, Mills 50W alloy resistors,Kiwame resistors
I hope it sounds as good as it looks, don't see why not but I am a bit of a tart when it comes to what it looks like

got some nos Sovtek 2A3s and some Sovtek ECC83 from jibbles

one thing, I am a bit worried about these reports that modern GZ34 let go,
were they just isolated or should I invest a large sum of money in a Mullard, I hope not, I'd rather put the money ino a Wkz
anyway, it should be up and running very soon now
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  #3  
Old 31st December 2005, 02:08 PM
Global Global is offline
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Default Re: Loftin White

Hi David

Has jibbles resumed eBay selling? I thought he had stopped.

Mark
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  #4  
Old 31st December 2005, 02:12 PM
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Default Re: Loftin White

he had a bad car accident and had to stop for a while but is now back on ebay
the same as before
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  #5  
Old 31st December 2005, 02:37 PM
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The Shadow The Shadow is offline
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Default Re: Loftin White

Hi Andrew/David

My current set up has bog standard components Sprague caps etc. It uses a star power and earth topology and has the Hammond 125FSE output transformers.

As Simon alluded to in the old WAD forum I run an MJ Acoustics active sub for the bass and use KEF KMS 2002 uniQ egg speakers as satellites.

The LW amp drives the sats full range from the first output of my Pre II, the natural roll off at 100Hz of the 125FSEs working with the 80Hz roll down of the sats.

The bass is driven from the second output of the PRE II with the crossover set at an 80Hz upper limit.

I only have a 12ft x 12ft room which the whole family use so I simply cannot use big high efficiency horns. They'd boom like hell and I'd probably end up in the divorce court so the active bass with satellite route is the way to go for me.

It really works too as Simon will testify. His version kicked some serious butt in that room with those giant 1627 OPTXs making the mid and top fast and serious. It seemed to go lower too but I don't know how or why as his amp was not involved with bass duties, that being handled by the Pre II and subwoofer.

Regarding your concern David with modern GZ34s blowing. I decided to give JJ a second chance on December 23rd. My 1967 Mullard CV378 which had given no trouble at all was given a rest but the second JJ GZ34 duly started arcing on Boxing Day. It had only been in 3 days. I'm not buying any more of them!

The CV378 (GZ37) was returned to its rightful place next to the mains transformer heading up HT duties and all is well once more. The Groove Tubes 5AR4 is supposed to be a bit more rugged at £19 from Hotrox but it looks like you might have to spend a bit to get a reliable rectifier or ask some of these chaps on here nicely.

Simon uses a GZ33 and I use the CV378. Both these tubes are less expensive at around £25 than a NOS Mullard GZ34 and work extremely well. If you use the CV378 the HT will be a bit lower than Phillip envisaged due to its bigger forward voltage drop and the 5v heater current draw is higher but the big Hammond mains TX does not seem to mind.

I've only got 3 Mullard ECC83s and they are used in the phono stage but I'm currently getting really good results from a pair of Sovtek 12AX7LPS driver valves. They are made for AC heaters having a spiral filament and are classic long plate designs. They are good value, very well made and make a lovely combination with the Sovtek 2A3s.

The least said about RCA NOS 2A3s the better. I WANT SOME! (weeps)

Time to start on the caps and resistors in the new year so I'll be looking for advice soon Andrew.

Long may this new BB continue.

Cheers

Steve

Last edited by The Shadow; 31st December 2005 at 03:55 PM.
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  #6  
Old 31st December 2005, 06:41 PM
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Martin213 Martin213 is offline
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Default Re: Loftin White

Steve,
Will we get 2 hear ur amplifier at Eggfest 3? You've obviously put a lot of time,thought and effort in2 it,i hope u can make it so we can all hear the fruit of ur effort. R u really the same person Naim'ed b4???
Kindest Regards
Martin
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  #7  
Old 31st December 2005, 07:55 PM
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Thumbs up Re: Loftin White

hi andrew tell me what speakers do you use with the lw ,did you use the kls3s interested to know as they are so low powered with the shadow useing a powered sub and others going the lowther route which can be very expensive, oh and how do the new black gates sound, by the way the kls3s are very good cheers tony b
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  #8  
Old 31st December 2005, 08:06 PM
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Default Re: Loftin White

Quote:
Originally Posted by Martin213
Steve, R u really the same person Naim'ed b4???
Kindest Regards
Martin
I am he.
With the Linn/Naim combination I was forever fiddling my musical taste was very narrow and the system dictated what I played.
Now I can play what I like and my musical tastes are expanding week by week.
That's what it's all about in the end. I'll definitely get it to EggFest 3 because this time I'll be able to book time off well in advance.

The Phil Ramsey LW is a great amp

Steve.
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  #9  
Old 31st December 2005, 08:25 PM
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Default Re: Loftin White

Steve
I've got a Sovtek 5AR4 so maybe that'll be OK,
good to hear the lps ECC83 work well as I'll have wait for Mullards
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  #10  
Old 31st December 2005, 10:13 PM
simon2a3 simon2a3 is offline
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Default Re: Loftin White

Hi All,

So Andrew, do tell, what difference has the WKZ made??? Is it worth the brass?

I also had a problem with the original GZ34 (Chelmer Valve) which arced on switch on. Rather disconcerting for a first time scratch build. The replacement Chelmer worked okay, and the Mullard GZ33 has been fine (touch wood). I do have a couple of JJ GZ34s waiting to go into my WE300b monoblocks (when I eventually get them finished) and I'm a little concerned about Steve's experience with them... Guess I'll just have to get some Mullards...

I agree with Andrew about the improvement the Mullard ECC83s brought over the original stock Svets. Very nice indeed. Don't know about amorphous yet, but Andrew has done an excellent job as a TX salesman so that's the next big investment.

Simon.
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