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DSJR
19-12-2009, 14:21
Apologies if this is in the wrong place and given its own thread, but going back a couple of months, I remember a thread regarding valve life and the suggestion to test your valves before condemning them..

I'm not in a position to test the valves in my preamp, but I was very pleased indeed with the 5841a's which replaced some very suspect sounding ECC82/12AU7's in the line stage.

Fairly recently, I noticed the phono stage was sounding brighter and brighter, making the OC9 totally unlistenable. Eventually, even the Supex 900e went bass light and a frantic PM to our beloved leader gave me a source of possible good replacements..

My Croft is rather more complex than the current Series 25 models, having three valves in the power supply and four in the phono stage, as well as the two line valves. The supply valves consist of a black regulator valve, an EL86 and an ECC 83 which was a "Golden Dragon" type. The four ECC83's in the phono stage were un-named types which looked similar to the Golden Dragon one.

Four CV4004's and NOS Mullard ECC83/EL86 later I was ready to go..

The first thing is that the slightly excessive but likeable brightness on the line inputs has been suitably tamed. "Timing" and clarity seem further enhanced, making the compressed noise from commercial radio stations easier to tolerate and little percussion and phasing effects on the first Ulrich Schnauss CD's more clearly delineated.

The biggest improvement was in the phono stage however. The bass has come back with no bloat at all and the OC9 is now sounding lean but clear and with some measure of bass clarity as originally - as much as the Dual will allow it to anyway..

So, I'm a happy bunny and back to playing records again :) The CD player is still a bit sick but appears to be recovering all on its own, getting better each time I use it..

Here's to some great Xmas choons.........

Ali Tait
20-12-2009, 12:19
Good to hear you got it sorted.The main problem with NOS ECC83 is the price!

chris@panteg
20-12-2009, 14:02
Nice one Dave ' a valve pre like the Croft is hard to beat ' what was your CD player again ? .

DSJR
20-12-2009, 15:24
It's a Micro-Seiki CD-M2...

http://i132.photobucket.com/albums/q8/DSJR_photos/cd-m2-h.jpg




The Croft pre valve update... The inductor by the transformer now removed as per Glenn's instructions..

http://i132.photobucket.com/albums/q8/DSJR_photos/Croft4PPrecap1.jpg

chris@panteg
20-12-2009, 15:56
Hi Dave

I heard the Micro-Seiki ' at the Bristol show (1990) AS room with Ricardo in attendance ' at the time i thought it one of the better CD player's i had heard.

The Croft looks very interesting ' and so different to my old Concordant pre



I had mine modified ' new pots ' cable ' internal wiring ' but the most fundamental change was Star earthing ' as the original had Doug's odd earth loop ' going from pot to pot ' he called it the endless earth loop ' .

Themis
20-12-2009, 16:19
The Croft pre valve update... The inductor by the transformer now removed as per Glenn's instructions..... and ?

DSJR
20-12-2009, 17:17
I didn't notice any difference... The input dropper resistors across the phono line in's removal and the valve changes accounting for practically all of it......

Glenn has more in mind as upgrades, but to be honest, I'd rather leave it be and, when the time comes, replace with a new preamp. I believe Glenn would like to do a two box re-think on the Mega Micro ideal (loads of separate power supplies) but whether the market would stand it is another matter - things is tight out there....

Themis
20-12-2009, 17:33
things is tight out there....
You bet... my Cyrus has been on sale for 3 weeks and is not sold yet... :(

DSJR
20-12-2009, 19:03
Hi Dave

I heard the Micro-Seiki ' at the Bristol show (1990) AS room with Ricardo in attendance ' at the time i thought it one of the better CD player's i had heard.



The CD player you heard was almost certainly the sample I own, as there were tell-tale marks on Ricardo's dem one which mine shares..

I had a Trichord Clock 2 fitted aeons ago, along with a new laser in 1997 and it sits on a Sicomin support, which had a similar difference to the clock mod for some reason (this machine is even heavier than the CD94 from which it's derived). The cracking *seems* to have abated with recent use (hope so) and when used from the balanced outputs (using hot and return pins) the sound is still good and very musical/three dimensional, if not quite as powerful as the replacement and far more expensive CD-M100....

chris@panteg
20-12-2009, 19:11
Well well

The system i heard it with comprised an Audio research SP11 and hybrid power amp ' a pair of sonus faber compact speaker's , ohh and a Goldmund studio DD turntable with siltech cable's .

It sounded superb with an out of the box 3D sound stage i had not heard before ' certainly not my system of the time anyway.

DSJR
20-12-2009, 19:19
Yeah, it was the first CD player I heard that could do a 3-D soundstage when asked. It was way ahead of the Naim CD-S at the time (we compared them, although our sales director wouldn't/couldn't(?) accept this as "Salisbury" were the only firm who could make HiFi gear...........

Post laser replacement, I took it into work and, once given two or three hours to "warm-up" (many of these old TDA1541 based machines needed this), it also easily saw off the harsh Naim CDX and spacially flat Linn Ikemi, although I could get great results from a carefully set up (regards to mains isolation) Karik III/Numerik III and the CDS-2/XPS was better and more like the CD-M100 in bass power....

http://i132.photobucket.com/albums/q8/DSJR_photos/ThreeD_60sstacked.jpg

http://i132.photobucket.com/albums/q8/DSJR_photos/DSCF0388.jpg

chris@panteg
20-12-2009, 19:34
I thought the CDS was a nice sounding machine ' but it could not do the 3D thing like the Micro.

i hope you keep it always Dave ' a nice piece of Hifi history , certainly brings back memories for me ' i used to really enjoy going to Hifi show's back then .

Very sad ' i know but well there it is .