2254C build/support thread

[Igor]

Actually, 1ma meter should be used, but you can fix it with 500r multiturn pot, connect:
meter + to wiper;
meter - to min pot's pos;
meter's - and pot's min pos to gnd;
meter gr signal to max pot pos.

 

[syn]

Thank you

 

[kml23956]

Igor,

Sorry for my ignorance.  Does a power supply board come with the 2254c boards or is that seperate?

Kevin

 

[syn]

it is a separate board and it does not come with the 2254 boards.you could use anything that can provide
adequate power and Igor has PSU boards for sale- see white market.

 

[guitarmaker]

Can 1000uf cap substitute for 680uf cap in position C4?  That's what my kit came with but I wanted to make sure it'll be okay in that position.  Thanks.

Steve

 

[TomWaterman]

Mine is the same as Steve, will look at schemo asap, but I assumed 1000uF is OK there... havn't fitted yet. No time to finish for a few weeks. About 85% soldered up.

-T

 

[Igor]

1000uf cap is fine here, I used same on my 2254C. All caps in kits are good quality.
Power supply was offered separately for minor cost to keep price of kits low as possible.

 

[user 10827]

Hi Igor,

Got a slight problem with the R44 10r resistor smoking when connecting the output transformer, disconnect and it stops and all seems ok,

Im using the VTB9049, primary connections are 1 & 3, whilst joining 2&4.

so that all seems normal, and ideas Igor?

Cheers

Pete

 

[user 10827]

Got it, was the smallest of shorts on the 2n3055. Got to make sure those heat sinks are lined up correctly!

Any hoo it works! ha ha..sounds bloomin great!

schweet!

;D

 

[matta]

We want pictures!!! Did you use a kit or your own parts? I'm still sourcing a few of mine...

Cheers

Matt

 

[user 10827]

Hi Matt,

well not much to see right now, this time i wanted to test the unit, make sure every thing works like it should then get the front panels made, rather than my normal do the front panel first and wish id waited!!

so i built 4, and i used the parts Igor supplied, Id be interested to know how much cheaper it would be to source the parts my self mind.. not alot in it i suspect..

the HPF is super cool on this, I have only tested it on drums, pushing it to the crushing extremes, sounds fab!!

So tomorrow will see calibration, more tests and measurements, make sure its all working and functioning and case em up!

;D

 

[bradb]

Yeah. Let's see some pics. I still just have a pile of parts and haven't started.

Can the psu transformer be sourced from mouser?
 

 

[user 10827]

Hi all, work in progress,

all working and calibrated, sounds wonderful!!

just need to finish my front panel design and hook it all up..

 

[solderspongebob]

That's over £500 in transformers alone!!! Holy coils Batman!

 

[Igor]

Holy **** dude!!!!
Nice pics!!!!

BTW, how does Carenhills sounds here?

Id be interested to know how much cheaper it would be to source the parts my self mind.. not alot in it i suspect..

I think same money as kit-pcb's...unless you building 100 units

 

[jplum]

Great Pics!

What info did u use to callibrate the units ?

cheers

 

[user 10827]

What info did u use to callibrate the units ?

just look at the circuit diagram, I think its then pretty obvious, if you are not sure i can tell you when i get home at look at the diagrams no sweat..

 

[kambo]

transformer molex connection guide
,
use with your own risk. check with audiomaintenance.com carnhill guide, and schematic

report errors....

9046 line in
primary :
short pin 3-4
connect 2(+) - 5(-) to molex

secondary :
short pin 8-9
connect 7(+) - 10(-) to molex
connect 6 to GRD molex

9045 interstage :
primary :
short pin 3-4
connect 2(+) - 5(-) to molex

secondary :
short pin 8-9
connect 7(+) - 10
6, ground molex


VTB 9049 output :
primary :
short pin 2-4
connect 1(+) -  3(-)

secondary :
short pin 6-7
connect pin 5(+) - 8(-)
ground the chases


thank you
kam

 

[timcas]

I've been using the Sowter 200:600 gapped output tranny for Neve-type line drivers for some years.
Never had a Carnhill to compare, but they seem to work well and many pro engineers have liked
the sound. Problem is, in the USA, poor dollar-to-pound ratio and high shipping makes them pricey.
I just got an Altran (altrancorp.com) version, and can not sonically tell it from the Sowter. It measures
very close in inductance and resistance, and looks the same on the scope. The good news -
$25 @ quantity 1. Definitely worth a try. Should work fine in this excellent project that I would certainly
love to build and use.

 

[user 10827]

Hi Chaps,

Work in progress still, waiting on a Marconi knob, but its up and working!!

sounds bloomin lovely! taken me ages to calibrateit so both sides are doing the same thing!!

the odd thing is when calibrating the meters, if for example you change the attack or release times, the meters seem to go out of wack a little with respect to each other, it may or may not be a problem for you, i am using 100ua meters and needed a 500ohm pot before the meter, the trick was to get the right balance from the 500ohm pot and the onboard adjustment.

Igor, re the  Link function, when engaged the right side is pulling slightly more GR than the left, is there some thing i can do to balance when in link mode that does not affect the unit when not linked?

any how pics so far....need to tidy up in side yet...