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Themis
20-08-2011, 09:01
So, the amps are gone to Glenn for some upgrades:

The Micro should have a larger toroidal transformer, regulated ht supply, better line stage, better resistors in the phono stage and some better phono sockets.
The Power should have a better amplifier section, regulated ht supply, larger toroidal transformer and better phono sockets.

Knowing Glenn, these should be worth the wait (and the price ! :eyebrows:) :stalks:

The amps should be back soon, so I start this thread to give my first (and following) impressions about these upgrades. :cool:

... and some pics inside-out too !
:mex:

DSJR
20-08-2011, 09:44
But why change what's really good already?

Oh, I know, BECAUSE YOU CAN!!!!! :peace:

Wouldn't you have been better just changing to the "R" versions?

Don't mind me - I know Glenn has all sorts of ideas in his head and it's just demand or the state of the audio market preventing him from bringing some of these ideas forward (at higher cost than the current products).

OF COURSE we want piccies and details please. It'll be interesting to see how the sonics change as well, not that theirs much to change IMO.

Themis
20-08-2011, 09:54
But why change what's really good already?

Oh, I know, BECAUSE YOU CAN!!!!! :peace:
Spot on !!! :lol:

Seriously, you're absolutely right, I'm extremely happy with these amps, I don't expect so much out of the upgrades... but I like being surprised (to the better) ! :eyebrows:


Wouldn't you have been better just changing to the "R" versions?

Don't mind me - I know Glenn has all sorts of ideas in his head and it's just demand or the state of the audio market preventing him from bringing some of these ideas forward (at higher cost than the current products).

I guess that most of these changes are included to the "R" version. But I'm not sure... I simply told him I had some money to spend and asked him about what could he do. These are the upgrades HE proposed, so we will see !

(and I hope he will be able to do them soon, I'm getting a bit impatient)

DSJR
20-08-2011, 09:57
:lol: :cool:

:grouphug:

StanleyB
20-08-2011, 10:52
By the way, Glenn now uses a Gatorized Caiman for additional auditioning ;). I have been using his amps for a few years now for the same purpose.

Covenant
20-08-2011, 12:21
Hey Dimitri,
Where have you been-welcome back!
I now use a Series 7 with a Caiman as a pre-amp. Would love to know the benefits of upgrading so a FULL report please!

basnas
20-08-2011, 18:22
Hi Dimitri.
My Croft is also upgraded. again super service from Glenn Croft
My series 7, is with regulated power supply and larger power transformer now. A big step to the Series 7R.
I will put some picture later of my Croft upgrade
Best Jan

Covenant
20-08-2011, 18:46
If you dont mind me asking Jan, whet sort of cost are we talking?

basnas
20-08-2011, 19:06
Hi
Ask Glenn and get a price, it is the best i can say.
Best Jan

Covenant
20-08-2011, 19:21
Probably best if I dont ask at the moment. Too many boring household things to buy like a new garage door.....:(

Thing Fish
20-08-2011, 19:24
Just been on the 'Croft Acoustics' site. Nice looking stuff indeed. Anyone else recommend these as a viable pre power combination...?

basnas
20-08-2011, 19:27
Croft Series 7 with the upgrade.
https://skydrive.live.com/?cid=7f23e0ff95f69dce&sc=photos&id=7F23E0FF95F69DCE%21188#!/?cid=1a761fa490d08000&sc=photos&uc=1&id=1A761FA490D08000%21116!cid=1A761FA490D08000&id=1A761FA490D08000%21119&sc=photos

basnas
20-08-2011, 19:30
Croft Series 7 with the upgrade.
Try again

DSJR
20-08-2011, 20:27
It's fantastic that Glenn can do a sort-of halfway house with the Series 7, but really fellas, a 7R would be a lot better again and in the wide HiFi world out there, with Naim's equivalent costing more than double the "R," I think £1400 is incredibly cheap for what's on offer :)

hifi_dave
20-08-2011, 20:35
Just been on Croft Acoustics sight. Nice looking stuff indeed. Anyone else recommend these as a viable pre power combination...?

Definitely..:thumbsup:

Themis
20-08-2011, 20:59
Croft Series 7 with the upgrade.

Hey ! Very nice !!! :stalks: Thank you so much Ian for the pictures !

And what were the sonic differences that you noticed ? :)

Themis
20-08-2011, 21:02
It's fantastic that Glenn can do a sort-of halfway house with the Series 7, but really fellas, a 7R would be a lot better again and in the wide HiFi world out there, with Naim's equivalent costing more than double the "R," I think £1400 is incredibly cheap for what's on offer :)
Well, next upgrade (perhaps next year ?) maybe ?! ;)

Thing Fish
20-08-2011, 21:09
Definitely..:thumbsup:

Perhaps its finally time to stick the Naim boxes on fleabay...:hmm:

Themis
20-08-2011, 21:21
Perhaps its finally time to stick the Naim boxes on fleabay...:hmm:
Dave, I'm not a big specialist in hifi (relatively and all that), but, in all modesty, I would strongly advice to give them a listen.
The Power amp can handle difficult speakers with authority and ease without congesting them, and the Preamp is a caress to the ear with an excellent phono stage and utterly transparent line inputs. An amazing thing for the price, really.

Thing Fish
20-08-2011, 21:29
Thanks for the advice Dimitri...:)

DSJR
20-08-2011, 23:21
To get anything remotely "better" - and this is a matter of opinion obviously as the presentation is different - you're going to have to go to serious money with the new Albarry's for example. The latter's power amps are truly sublime, but double the price of the series 7 "R." my jury's out on the Albarry preamp for now though, although it looks fab, a doddle to use, doesn't hum with a Decca (:eek:) and just, well, does the business :)

The thing is, I've only heard the current Crofts as supplied. I'm sure some/most of the extra "finesse" of the much dearer products could be acheived by simple valve swapping, as I've found with my old 'un and, of course, it's all a matter of opinion, as the Crofts in stock form seem so "honest" and "straight" with the signal fed them.

Welder
20-08-2011, 23:41
Hmm, I rather like the some of the old Naim kit.
My objection to Naim was never how they sounded; it was how much the kit cost.
I know Naim kit isn’t popular on this forum but they’ve produced some excellent sounding amps over the years ;)

Covenant
21-08-2011, 08:23
The thing is, I've only heard the current Crofts as supplied. I'm sure some/most of the extra "finesse" of the much dearer products could be acheived by simple valve swapping, as I've found with my old 'un and, of course, it's all a matter of opinion, as the Crofts in stock form seem so "honest" and "straight" with the signal fed them.[/QUOTE]

I imagine the power amp is unlikely to benefit from a valve upgrade?

DSJR
21-08-2011, 11:24
No, but the preamp might :)

VERY old Naims, such as the bolt-up 120 and 250 will make superb valvey sounding power amps. The shock when the harder-hitting and almost harsh sounding CB range was launched is still strong thirty or more years later... Thing is, old bolt-up 250's may not be stable these days as I remember one failing, taking out some Sara's and it took Naim's service dept a good while (weeks rather than days) to reliably/permanently fix the amp boards. Put it this way, we didn't take on EAR 509's because the bolt-up 250 sounded so close, but slightly better in the bass. had Tim brought these amps to us a couple of years later when the CB range was in production, the 509's would have easily won :)

Themis
26-08-2011, 19:37
No, but the preamp might :)

VERY old Naims, such as the bolt-up 120 and 250 will make superb valvey sounding power amps. The shock when the harder-hitting and almost harsh sounding CB range was launched is still strong thirty or more years later... Thing is, old bolt-up 250's may not be stable these days as I remember one failing, taking out some Sara's and it took Naim's service dept a good while (weeks rather than days) to reliably/permanently fix the amp boards. Put it this way, we didn't take on EAR 509's because the bolt-up 250 sounded so close, but slightly better in the bass. had Tim brought these amps to us a couple of years later when the CB range was in production, the 509's would have easily won :)
Once I asked Glenn about tube rolling in the 25 pre and the response was something like "do as you want, but ... the Tesla are very good imho"
I translated this as "you can spend your bucks if you want but believe me I put the best tubes I know of inside".... :)

Themis
26-08-2011, 19:38
Breaking news ! : Glenn finished the updates yestarday, the amps are on their way home !!! :partytime:

hifi_dave
26-08-2011, 20:23
Pity he doesn't stop jerking around doing mods and get some of my orders out..:rolleyes:

Themis
26-08-2011, 20:57
Pity he doesn't stop jerking around doing mods and get some of my orders out..:rolleyes:
Well, Dave, it took more than a month for the upgrades, that is...

StanleyB
27-08-2011, 07:12
Glenn used to take a month off around June to August. If he still does that, then it could explain the stock delays. Adrian at Audioflair mentioned to me that he has seen an increase in requests for mods on the Croft range, so Glenn must be running slow, causing people to go to Adrain instead.

DSJR
27-08-2011, 09:35
How can you modify perfection? :peace: :lolsign:

Believe me - and other Croft owners - the basic units as supplied are bloody good and basic component "upgrades" are only going to make small differences IMO. the mods as done to Themis' units by Glenn are a bit more fundamental I think and where any serious sonic refinements may be gained?

Themis
27-08-2011, 09:44
How can you modify perfection? :peace: :lolsign:

Believe me - and other Croft owners - the basic units as supplied are bloody good and basic component "upgrades" are only going to make small differences IMO. the mods as done to Themis' units by Glenn are a bit more fundamental I think and where any serious sonic refinements may be gained?
I fully agree with you Dave ! :cool:

I will make a full report when they arrive, and try to ask Glenn about the details when needed, but you have to bear in mind that I lack confidence to my long-time hearing memory, so I will try and keep the changes in perspective. ;)

DSJR
27-08-2011, 10:31
I lack confidence in my hearing - period :D

Good luck. I know you'll enjoy the results. The thing is, in a market as small as this is now, there's no point in making several different versions 'cos all it will do is cause confusion. Twenty five years or so ago, Glenn could make, oh, five or more versions in his "range," but sadly not today, hence the Basic (which is still pretty darned good), the Micro 25 proper, which is more refined and then the "R," which looks more sophisticated just by peering in the top grille. Glenn was talking about a higher "Mega style" preamp in two boxes with extra power supplies, but whether the market could take this is another story.

Themis
27-08-2011, 10:35
Why not a preamp, a power and a common (to both) external power supply ?

I would be ready to consider such an option, actually. ;)

DSJR
27-08-2011, 10:44
Too many boxes I reckon - possibly.

tell you summat though, I was surprised how substantial the cases seem to be (for a croft ;)). the back and front panels are mounted on a solid internal frame, allowing the new knobs to be inset a few mm - they really do enhance the appearance and make it easier to set balance visually. I'm probably going to try some Brennel style elongated knobs on mine I think - chicken-head just doesn't look right and I can't easily see the indents on the brushed knobs mine has..

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

Marco
27-08-2011, 11:00
Believe me - and other Croft owners - the basic units as supplied are bloody good and basic component "upgrades" are only going to make small differences IMO.


Hi Dave,

Yup, the basic units are indeed very good, but there is still plenty of fundamental 'tweakage' to be had with Glenn's designs, and one of the reasons why the sonic rewards are so significant, is because the basic circuits are so good in the first place (therefore allowing any mods to realise the circuit's true potential)!

I bought my Charisma-X, in its original state, six years ago for £2k. To date, the following mods have been done....

Carried out by Glenn in 2008: removal of internal PSU and fitting of huge external PSU, with individual supplies for line-level and phono stage, using three separate large transformers. Removal of valve regulation (and 6080 regulator valve), and replacement with MOSFET. Fitting of Alps Black volume pot (replacing Alps Blue) and upgrading of all phono connectors to Eichmann solid-copper types.

Since then I have:

1) Upgraded the Alps Black volume pot to a high-quality DACT stepped attenuator.

2) Upgraded both the smoothing and power supply caps with SCR Teflons and Mundorf Tubecaps.

3) Changed all valves originally supplied with the preamp (Ei ECC83/Mullard 85A2, Russian-derived and NOS RCA 6SL7s, five valves in total) for NOS 1963 Mazda 12AX7/NOS Amperex 85A2/NOS 1954 GE 5691 x 2/NOS 1952 Sylvania 6SL7WGT x1/NOS 1945 Tung Sol 6SU7GTY x2.

And, Mr Rance, the cumulative sonic effect of all of the above has amounted to rather more than "small differences"!! ;)

Approx a further £2k, in total, has been spent on all the above modifications, which granted is significant, but I've now got a £4k preamp which sounds as good as any I've heard at £15 or £20k!!

So yes, Glenn's basic designs are very good indeed, but with some judicious modifications, such as I've outlined above, they can be turned into just about the best preamps one can buy at any price.

Marco.

StanleyB
27-08-2011, 12:05
Pity he doesn't stop jerking around doing mods and get some of my orders out..:rolleyes:
I doubt that mods are the reason. He's a cricket fan and is likely to be following the England team round the country. So expect some more delays till the Indian tour is wrapped up.

Marco
27-08-2011, 12:24
Spot on, Stan! I'm surprised you never thought of that, Dave ;)

Marco.

hifi_dave
27-08-2011, 13:05
It's cricket.

With Glenn, everything stops for cricket..:rolleyes:

Actually, he has started sending out my orders now so, I guess, rain stopped play !!!

Themis
27-08-2011, 15:04
:lolsign:

DSJR
27-08-2011, 21:23
Hi Dave,

Yup, the basic units are indeed very good, but there is still plenty of fundamental 'tweakage' to be had with Glenn's designs, and one of the reasons why the sonic rewards are so significant, is because the basic circuits are so good in the first place (therefore allowing any mods to realise the circuit's true potential)!

I bought my Charisma-X, in its original state, six years ago for £2k. To date, the following mods have been done....

Carried out by Glenn in 2008: removal of internal PSU and fitting of huge external PSU, with individual supplies for line-level and phono stage, using three separate large transformers. Removal of valve regulation (and 6080 regulator valve), and replacement with MOSFET. Fitting of Alps Black volume pot (replacing Alps Blue) and upgrading of all phono connectors to Eichmann solid-copper types.

Since then I have:

1) Upgraded the Alps Black volume pot to a high-quality DACT stepped attenuator.

2) Upgraded both the smoothing and power supply caps with SCR Teflons and Mundorf Tubecaps.

3) Changed all valves originally supplied with the preamp (Ei ECC83/Mullard 85A2, Russian-derived and NOS RCA 6SL7s, five valves in total) for NOS 1963 Mazda 12AX7/NOS Amperex 85A2/NOS 1954 GE 5691 x 2/NOS 1952 Sylvania 6SL7WGT x1/NOS 1945 Tung Sol 6SU7GTY x2.

And, Mr Rance, the cumulative sonic effect of all of the above has amounted to rather more than "small differences"!! ;)

Approx a further £2k, in total, has been spent on all the above modifications, which granted is significant, but I've now got a £4k preamp which sounds as good as any I've heard at £15 or £20k!!

So yes, Glenn's basic designs are very good indeed, but with some judicious modifications, such as I've outlined above, they can be turned into just about the best preamps one can buy at any price.

Marco.

Yeah, but noone except a big daftee like you would spend £4K on getting your old preamp up to current "R" spec (I believe you did the comparison and it wasn't as huge as you wished? - perhaps I got it wrong :)) :peace:

Remember, if you throw enough money at a product, anything is possible, the secret is how bloody wonderful a Micro Basic is for £400 or less :lol:

Anyway, your preamp can't be any good whatever you've done to it - it's only got ONE volume control :D

P.S. :respect:

Marco
27-08-2011, 21:51
Lol! You're right (to an extent)...

I compared an 'R' spec Croft preamp to my modded Charisma-X about 2 years ago, and the difference wasn't huge, but that was before the DACT stepped attenuator, new smoothing and power supply caps, and NOS valves arrived! ;)

The point I was making, though, was that judicious modifications to Croft preamps *can* result in much more than small (and indeed give very worthwhile) differences :)

Marco.

Themis
02-09-2011, 08:04
Ok, guys some good news :

The amps arrived a few days ago, but I was not at home, my son received them. :eek:

I hooked them up this morning, but I can't do any serious listening, nor serious photos (with a proper camera), let alone a proper review, as I'm in preparations for my trip to Philippines (couple of days left). :(

Soo....

Glenn added three more valves to the preamp and changed the brand of all the valves. :scratch:
The power weights a ton, now, I didn't open it but I suspect he put a huge toroid inside (the box, as you know, is not heavy on its own. BTW : I thank Glenn for not having chosen excessively heavy boxes, as some manufacturers do, I really appreciate !)

They surely sound different, but, all what I can say, the amps sound easy !!! Easy, like a Sunday morning ! ;)
No point in saying much about the sound, I'll have to leave them settle a little. :) But, what strikes most is that they are much quieter than before. The sound is as black as the front, now. :eyebrows:

Covenant
02-09-2011, 08:39
Can you still hear a hum from the transformer when there is no music playing?

Themis
02-09-2011, 09:04
Can you still hear a hum from the transformer when there is no music playing?
There used to be a small zzzzzz, indeed, that you could hear from about 1,5m away.
Now there is an extremely low sssss (I would say about -9dB to -12dB lower than before, the frequency is slightly higher) but I need almost to stick my ears to the tweeter. Nothing comes out from the midrange or the woofer. I can't hear it from 20cm away. And it is independent of the volume (I put it all way long, it doesn't change). So, it can as well not be the amp ? :scratch:

Themis
02-09-2011, 09:34
Some photos of the preamp (using the phone:( ):

http://i589.photobucket.com/albums/ss339/Themis_photo/Croft%20updates/IMG_0269.jpg
http://i589.photobucket.com/albums/ss339/Themis_photo/Croft%20updates/IMG_0270.jpg
http://i589.photobucket.com/albums/ss339/Themis_photo/Croft%20updates/IMG_0271.jpg

DSJR
02-09-2011, 12:07
I could be totally wrong here (:lol:), but it looks as if you have a valve regulated supply to the phono stage. The extra two valves look like they're a separate "push pull" line stage as fitted to the "R" (and also my old Series 4 PP). The second transformer is interesting and I wonder if this would be any better in mine?

The thing is, Glenns refined circuits can be supplied effectively in many different ways. the old Mega Micro used octal valves, but each stage had extensive supplies fitted in a separate box. I'm not sure how far from an "R" your example is, but I bet it's bloomin' close.

Now, you MUST get the new knobs (from RS I believe) to finish it off :)

http://i132.photobucket.com/albums/q8/DSJR_photos/964e8194.jpg

Themis
02-09-2011, 12:24
Thanks for the insight, Dave ! :) ("totally wrong", haha :lol:)

Do you have a link for the knobs, just in case ?

Themis
04-09-2011, 08:42
Guys, I'm on my way to Philippines, shortly, so, no more news before I'm back home (ie 3 weeks). ;)

DSJR
04-09-2011, 08:53
Not too dissimilar to these I think -

http://uk.rs-online.com/web/p/knobs-dials/4672491/

I bet Glenn would sell you some at little more than cost anyway if you were interested :)

Themis
04-09-2011, 09:03
Not too dissimilar to these I think -

http://uk.rs-online.com/web/p/knobs-dials/4672491/

I bet Glenn would sell you some at little more than cost anyway if you were interested :)
Thank you Dave !!! :)