Pre-Amp bake-off - What Happened...

[montesquieu]

I've had a TVC using S&B transformers in my system. I really liked it. Differences between the croft and the TVC was that the TVC was more delicacy transient whilst the Croft's main advantage was drive. Nothing wrong with either for me, just different.

Thought you had the Pure Sound pre?

Not for a while ... went integrated for a bit then had various, Glasshouse passive, C-J PV14L, Tram2.

I would agree to some extent on the lack of drive on some TVCs, wasn't fussed with the Prometheus, Music First V1 was better, but the MFA MK II, with the V2 transformers in (25% bigger and not sold to anyone outside MFA) the clarity, space, soundstage etc is all there but no drive whatsover is lost, to my ears at least. This stacks up really well against both the C-J and the Tram2, and that into a power amp (Lyngdorf SDA2175) that is renowned for needing an active pre as it's not all that high gain. And compared to any valve pre I've heard the 'blackness' is stunning.

With most types of music, I'd take drive over delicacy every time - especially when the valve preamp in question is also, erm, none too shabby at the latter!

Marco.

I'm not a huge fan of the Croft pres to be honest. Those I've heard have been musical, but compared to more high-end valve preamps (never mind the TVC) they have left a bit to be desired in terms of sophistication ... more to it than delicacy, more about naturalness IMO. Jolly good fun though. But my diet is mainly classical, in rock'n'roll sophistication isn't necessarily the name of the game. It's not really a criticism of the Crofts, I do think they are fantastic value for money but they are hardly the last word.

As far as any passive goes I think it's entirely down to synergy with the power amp, I don't think TVCs are a panacea by any means, but where there are no impedance issues (as there generally aren't with a TVC) and there's a nice healthy gain on the power amp (perhaps a juicy tube input stage), there's a fair chance an active pre will only muddy the sound to some extent. (Whether you enjoy the mud is a different issue entirely!).

[Marco]

Hi Tom,

No mud here, muchacho! Only beautifully clean white sands

The Croft I'm using has been very heavily modified, so probably unlike any other you've heard. Whether you'd like how it sounds or not, however, is another question.

We've been threatening to have a bake-off for a while, so perhaps I could bring the Croft down and you could compare it in your system to your TVC?

Marco.

[Alex_UK]

Great thread guys, and fab write-ups from all of you - sounds like it was a great day spent with kindred spirits listening to great tunes on great hi-fi with great food & drink - feck, it sounds like heaven!

[Marco]

Hi Marco,

I think sometime back you had the opportunity to listen to the Croft Micro 25RS, how did this compare with your Charisma X and what were your thoughts in general regarding Glenns top of the range Pre?

Hi Jim,

One of my mates had a loan of a 25RS, and it was very good indeed. However, we both preferred my own Croft. The main difference, sonically, is the influence of the bigger valves used in the C-X, as the musical presentation of 6SL7s is very different from that of ECC83s (or other small signal valves) - and that difference superimposes itself rather significantly on proceedings.

Marco.

[montesquieu]

Hi Tom,

No mud here, muchacho! Only beautifully clean white sands

The Croft I'm using has been very heavily modified, so probably unlike any other you've heard. Whether you'd like how it sounds or not, however, is another question.

We've been threatening to have a bake-off for a while, so perhaps I could bring the Croft down and you could compare it in your system to your TVC?

Marco.

Sounds like a plan Marco, would love to hear it. I'm currently awaiting arrival of a Radford STA100 from 1967 ... this arrived with a slightly sub-par output transformer. Radford Revival are winding a new pair from Radford's original spec sheets ... system sounds pretty good at the moment with the Lyngdorf but when that's here I'm hoping that will kick it up a notch. (Be an interesting comparison anyway). Anticipated in next 3-4 weeks. Wife is away most of August so maybe could pencil in a day and have a few more of the lads round?

The Radford STA100 thing is actually a wee bit more complicated ... it's one of those amps that have polarised opinion, those that have used it as a 100v line amp for studio work seem to think it's the best thing since sliced bread, but feelings seem to be more mixed for hifi use, perhaps in part because of optimisation for 100v line and 16 ohm speakers, rather than more modern 4-8ohm ... it's a bit borderline with 8ohm speakers especially cranked up a bit, which didn't help reliability.

Will and Steve have actually recommended winding a set of transformers from the TT100 spec sheet, one of old Arthur's very last designs which marked a return to valves after quite a few years in the 70s when Radford went solid state. The TT100 had a solid state front end but (I'm told) an almost identical power stage to the STA100 (100w from KT88s) except the OPTs are wound for 5.3ohm/8ohm nominal and the 100v line secondary has been removed - ie, exactly what we need to do to make the STA100 a proper hifi amp and probably more reliable as well (the TT100 didn't have the STA100's reputation for eating tubes). Graeme Hirst (Valvebloke/'Ampregen' is liaising with Will and Steve and knocking it into shape for me. (We'll keep the original transformers and everything done will be reversible).

It's low sensitivity so I'm anticipating that the TVC might be a better bet than an active pre (that's why it's here, in anticipation ....). But would be great to try the Croft on it.

If it all works out I'll almost certainly be giving it over to Radford Revival to do a full restoration on it (paint job, new boards etc). Their work is fantastic.

[Marco]

Hi Tom,

August could be good, mate. Swing me a PM when you've got a better idea of a date

Love Radfords!

Marco.