Carnhill 9600R:600R output transformer..... what uses ?

Would a 4:1 step-down Carnhill output transformer (of a similar style to the 600R:600R VTB2280/VTB2281) be any use to the forum members ?

I have asked Carnhill to make a couple of samples (gapped and ungapped)...... but I cannot remember what members wanted them for (apart from the LA2A) !

Colin
www.audiomaintenance.com

maybe it was me!

for the Daoc, but I ended buying some Utc-H13 wich are 10k/500r.
If you can have some at reasonable price I might be interested...

cheers.
Jr.

hi colin,
hope you're doing well!
the analag D-AOC and PM660 both recommend the edcor XSM 10K:600R output transformer.  i suspose that these projects would benefit from the carnhill.  
it would be interesting to see if they would work as an upgrade to the edcor which is rather cheap, but more than decent sounding for the price.
maybe you can get analag, [silent:arts] or bernbrue to do a test with a prototype from carnhill and take some measurements and notes on performance as compared to the edcor or other transformers, though i remember volker noting in his test of different output transformers in the D-AOC thread that they have little effect on the circuit and sound/freq. response as a whole (not sure about the PM660).
kind regards,
grant

it should sound similar, all the models i have seen use the same 75 EI with P- S- P- S- P config,

sowter uses a slightly larger stack, which gives the bass a slight boost, but other than that,

neve does reverse wind , neve i think of as marinair, so i mean marinair has a reverse wind, but no big.

slightly different resonant point, due to the shifting of the C leakage. no fancy alloy, all grain orient,

Colin I'm interested in a pair of Carnhill output transformers suitable for  DAOC / LA2 builds if you're thinking of stocking some?

Aha.... it was for a DAOC (I think) that someone wanted these....

Once they are done, a pair of Samples will go off to [silent:arts] to play with .... once we have some feedback (assuming it is good feedback), I'll get some in stock.

No idea of the price as yet..... they haven't as yet even been designed...... I would guess they will be more that the standard type (GBP 17.66) because they will have a lot more primary winding (4 times as much ?).

Colin
www.audiomaintenance.com

How are the windings configured in this one? does it have dual windings on both secondary and primary side (4 pins each side)?

What kind of output levels can it handle?

I've asked for dual primary and dual secondary and narrow connector PCB (so it fits in 1U box).... don't know the max level until samples get here (I am presuming it will be >+30dBu like the others).

Colin
www.audiomaintenance.com

Slenderchap said:

I've asked for dual primary and dual secondary

Click to expand...

Ah, so it's possible to wire them as 2400:600 (2:1)? In that case I have a project where they might come in handy.

JDB.

Slenderchap said:

Once they are done, a pair of Samples will go off to [silent:arts] to play with .... once we have some feedback (assuming it is good feedback), I'll get some in stock.

Click to expand...

8)
I will test them in the D-LA2A and the D-AOC for sure.
might be useful in another tube type analag project which is still in work too.

like jdbakker mentioned the dual primary and secondary windings could be handy for way more projects.

2 of each of the Gapped and Ungapped have now appeared on my desk so a pair of them should be on their way to Volker ([silent:arts]) be tested very shortly.

Colin
www.audiomaintenance.com

Colin, when will you have those on sale?
Cheers

Syn... that depends on Volker ([silent:arts]).... once he has tested them... assuming they sound the way they should.... then it would probably be about 4-6 weeks after that.

.... and I only posted them out to Germany the other day....

Colin
www.audiomaintenance.com

Colin
        thank you.

they just arrived
don't know if I will find some time today, and tomorrow is a busy day, but wednesday should be fine for testing this beauties ;D

There will now be 2 new Carnhill output transformers with 9600R:600R windings;

CA-18-VTB2290 {Gapped core}

CA-18-VTB2291 {Ungapped core}

They will have a narrow connector board to fit 1U box (like VTB1148).... and dual primary and dual secondary windings.

They should be in stock in about 6 weeks .... a little more expensive than the standard types (GBP 19.22)

Colin
www.audiomaintenance.com

excellent!  thanks colin!
always good to have reasonable options.  eventhough the edcors are cheap, i do like carnhills. ;D (just my personal taste).

if volker could post some of his thoughts, findings, readings from the test run that would be greatly appreciated i'm sure.

all the best this holiday season colin!
-grant

dissonantstring said:

if volker could post some of his thoughts, findings, readings from the test run that would be greatly appreciated i'm sure.

Click to expand...

I will keep my mouth shut until Im finished

Hi,
      Colin was very kind to send me one of each. Did not test these "scientifically" but I've run a quick test, by attaching each one to the output of the DAOC. I have to say it was not "proper" DAOC just P2P test version,
that I assembled in order to see "do I need this comp at all?". I do. It is very good compressor (I run full Kubi mods apart from input transformer that I kept 1:1). Input transformer is 10k:10K, that I wound my self on  Stancor core, from disassembled 4:1 Stancor input transformer.
Gapped Carnhill:has roll off starting @~10k and reaches ~ -0.3dB @20k so i would consider it to be "flat" 20Hz-20kHz.
Ungapped Carnhill:  I would consider it to be "flat" from at least 20Hz-30kHz.

Test was done thanks to RMAA  and m-audio audiophile 2496 in 96K mode, no high end pro equipment, as you can see. No zobels on either transformer secondary.
Both transformers sound good to me, but that is just my opinion. I like color and DAOC circuit has dominant 2nd
harmonic distortion (~0.1%@+4dBu 1kHz)  that gives very nice, "full"&"fat" sound (whatever that means) with soft and round "edges" but it is not  "dull" nor "damped", again IMHO.
Gapped has a bit reduced F.R. due to the "gap" and less inductance, and I don't think it is fair to test it like this as it is relay meant to be used in the situation where DC is present @ the primary, which is not the case here. I have no such a circuit at hand, at present.
I ordered some more transformers from Colin yesterday, as I'll be using those on my forthcoming builds.
Best
Milos