2254C build/support thread

[Igor]

@ultra-alex: can you send me this file too? Please!
BTW, what is cost for 2254C front panel when ordered at frontpanelexpress?

 

[haima]

can we host it somewhere (i have web space if needed) - i think lots of people would find it useful...

i'm pretty sure i'm going to get pete "grandmaster audio" to make me one of his lovely grey painted numbers though!

 

[ultra-alex]

@ultra-alex: can you send me this file too? Please!
BTW, what is cost for 2254C front panel when ordered at frontpanelexpress?

igor, email sent! i don´t know about the cost @ frontpanelexpress? i paid about 90 eur for mine at frontpanels.de.

i'm pretty sure i'm going to get pete "grandmaster audio" to make me one of his lovely grey painted numbers though!

i also got a panel from pete for the next unit. very very nice but not cheap though...
cheers, alex

http://www.groupdiy.com/index.php?topic=38500.0

 

[Rybow]

Ultra-alex- Is your FPD file for a stereo version or mono?

 

[ultra-alex]

stereo. 2RU.
http://www.groupdiy.com/index.php?topic=32605.msg463410#msg463410

 

[Igor]

@ultra-alex: thanx for sharing the file!
Regarding the N*ve logo. It was discussed many times before.
Let's give respect to Mr. Rupert. I hope this unit done for personal use only.
From the other side, excellent looking panels!
FPD is excellent service, not cheap, but quality worth this.

 

[jandoste]

Hi Igor,

Please can you give some idea for :

- which transformers !
can I use Mike's --> http://hairballaudio.com/shop/product_info.php?cPath=24&products_id=63

-Which Power Transformer !
can I use Mike's --> http://hairballaudio.com/shop/product_info.php?cPath=24&products_id=37

please more help for the kits !
Thanks,
cheers,

 

[ultra-alex]

- which transformers !
can I use Mike's --> http://hairballaudio.com/shop/product_info.php?cPath=24&products_id=63

-Which Power Transformer !
can I use Mike's --> http://hairballaudio.com/shop/product_info.php?cPath=24&products_id=37

please more help for the kits !
Thanks,
cheers,

go through this thread. all the help you ask for is already here...
transformer discussion (for example) on the first pages. most of us use carnhills. find here...
http://www.audiomaintenance.com.
regarding torodials. for example...
http://www.groupdiy.com/index.php?topic=32605.msg429071#msg429071
but of course any other 1A 24V will work fine.

 

[jandoste]

All resistors in kit are in +/-2% range, because sometimes I have in stock,
for example, 46.4 Kohm 1% instead of 47 kOhm 5%.

ouppssss ! I got all resistors from mouser and they are %1 ? so I got a ittle problem or they will work ?
Thanks
cheers,

 

[Rybow]

All resistors in kit are in +/-2% range, because sometimes I have in stock,
for example, 46.4 Kohm 1% instead of 47 kOhm 5%.

ouppssss ! I got all resistors from mouser and they are %1 ? so I got a ittle problem or they will work ?
Thanks
cheers,

Those will work just fine. It will actually make your circuit have a tighter tolerance.

 

[jandoste]

All resistors in kit are in +/-2% range, because sometimes I have in stock,
for example, 46.4 Kohm 1% instead of 47 kOhm 5%.

ouppssss ! I got all resistors from mouser and they are %1 ? so I got a ittle problem or they will work ?
Thanks
cheers,

Those will work just fine. It will actually make your circuit have a tighter tolerance.

Thanks Insomniaclown

 

[jandoste]

Hi All,
I can't fine 820 Ohms (Farnell France
Can I put 768Ω or 845Ω.  ?
Thanks

 

[haima]

820R is a common value - there's HEAPS of different ones available from farnell... try typing in "820R" into the search bar.

then filter the results:

* +/-1%
* axial/axial leaded
* between 0.25 and 0.6 watt)

etc

gets you heaps of results. like this one:

http://fr.farnell.com/multicomp/mf25-820r/resistance-0-25w-1-820r/dp/9342265

 

[jandoste]

820R is a common value - there's HEAPS of different ones available from farnell... try typing in "820R" into the search bar.

then filter the results:

* +/-1%
* axial/axial leaded
* between 0.25 and 0.6 watt)

etc

gets you heaps of results. like this one:

http://fr.farnell.com/multicomp/mf25-820r/resistance-0-25w-1-820r/dp/9342265

Thanks haima!
cheers,

 

[d.redfern]

Just some quick questions about this project (2254) and Igors 33609 project. Are these two separate? what are the differences in layman's terms? has anybody built both if they are different and what are there opinions?

Cheers for replies and sorry for asking dumb questions.
D

 

[haima]

they are similar projects... cousins i you like. they share the same gain reduction circuit and sidechain afaik.

2245c (igor's hybird combination of a few neve compressors):
* single ended class-A make up/output amp (like the output of a 1073 etc)
* sidechain high pass filter
* no limiter

33609 (very close to original 33609 neve circuit):
* option of original neve class-A/B or discrete opamp makeup/output amp
* no sidechain hipass
* limiter

people seem to love both of them. the 2254c is perhaps a little simpler to make, and sounds great - and the HP filter is a awesome addition.

 

[juniorhifikit]

Should I just change R"19 (in series with the gain trim pot)
from 820 Ohms down to something smaller? 
Or is there possibly something wrong elsewhere causing the gain to be too high? 

Higher r"19+trimpot less gain.
I have a strange feel that somehow transformers connected 1:4 instead of 1:2
or there's a wrong resistor somewhere....

Anyone else have trouble trimming down to unity gain?

Yes, some tens posts ago, lower gain....IIRC it was solved, good luck and tell us!

Sorry I haven't reposted back.  Still haven't been able to look into this as I'm booked on back-to-back mix projects and the 2254 is being used on all of them.  Even though it's not "correct" it still sounds great, and I can't change it in the middle of an album! ;D

FWIW, here's a song that has it on the drums (kind of like a Jellyfish/Queen song!):

The Posies

 

[jandoste]

Hi again All,
I got a quick question (newbie also
I got two LM317T
http://fr.farnell.com/national-semiconductor/lm317t/regulateur-ajust-1-2-37v/dp/9489398?Ntt=9489398
I already use one of them for the PSU and I need one more for TR1(JE371) if I use LM317T it will work or I need to buy the JE371 ?
Thanks,
cheers,

 

[haima]

TR1 is a bipolar transistor - not a voltage regulator (like the LM317T).

best to use a BD140 as per the BOM - try farnell order code 1574351:

http://fr.farnell.com/multicomp/bd140/transistor-pnp-to-126/dp/1574351

 

[haima]

FWIW, here's a song that has it on the drums (kind of like a Jellyfish/Queen song!)

sounds good! and it's great to HEAR your diy in action - there's surprisingly few sound examples on this board!