OEP vs Lundahl transformers in the 1176

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[quote author="gyraf"]?? I buy from Canford reguarily..??[/quote]
Just taken from the front page of the website...
There is a small entry in red which says they can;t do it currently
However it seems to have been there a few months
 
[quote author="gyraf"]Damn, that is sad news.. :?[/quote]
If you read it carefully it does says the web site only - I take it you can still phone or snail mail them
 
[quote author="peterc"]We have 3 channels of OEP & 1 of Lundahl, & the Lundahl chan is the least used. I have not heard a loss of high end, but there is definitely more "vibe" using the OEP's.

I also was hesitant about the OEP / Lundahl choice, but I love that unit.

Peter[/quote]

Hello Peterc,

I was wondering if you used OEP input and output or just output only?
Did you need the shield can (mu)?

Thanks,

Z
 
Mnats says on his page that the Mu shield can isn´t necessary. He tested it on his 1176.
Check this link: http://www.geocities.com/m_natsume/1176.html

By the way I got a note from Canford that Sifam meters will be awailable at the end of february.

cheers
Jens
 
You do know that Canford have a SIFAM VU METER R24A for £55 in the clearance section?
This is one of Sifams "proper" VU meters rather than the AL series which is the Presenation type meter
 
I was in Maplin today trying to get the correct resistors for my mini synth project (does no-one in there know how to read the colour codes?) and I noticed that they feature OEP audio transformers in their current catalogue, listed as NEW items. Unfortunately, being Maplin, they don't give the manufacturers codes.

http://www.maplin.co.uk/Search.aspx?criteria=n81cc&doy=27m1&source=15

Product code N81CC appears to be an A262A2E, but the 1+1:1+1 stat seems to indicate that p/c N82CC is in fact an A262A7E. It would appear that Maplin are being frustratingly eclectic in their product selection once again. Why they can't just stock the whole range like everyone else is beyond me.
 
i built a pair of units with electrically balanced in and 1+1:2+2 OEP output trannies.

then i built a pair of the fabio what (opto) compresors which used the 1+1:6.45+6.45 OEP's. it had waaaay too much output gain because i used the dip8 opamps instead of descrete 2520's.

so tried the 1+1:2+2 in the what opto, and the higher output jobbies in the place of the existing 1176 output trannies.

seemed to stuff the bias up on one unit - now is permanantly set to 'slam' mode.

next i built a pair of 1176's with 1+1:2+2 OEP input trannie and 1+1:6.45+6.45 OEP output.

one unit shows input signal but only outputs in bypass. the other is working fine (gobs of makeup gain) but at low levels there is oscilation.
i reckon it's the caps. previously used WIMA's but this time used these orange ones from rs components.

anyone got further comments on the 1+1:6.45+6.45 OEP as output trannie in the 1176?

chris.
 
anyone got further comments on the 1+1:6.45+6.45 OEP as output trannie in the 1176?

That one is a mic input transformer, not really useable as a line level output device because of it's rather high output impedance and early core saturation. Also, used for 1176, you may run the risk of burning out the driver transistor pair if shorting the output while carrying signal.

For OEP output iron, use 1:1 or 1:2 types!

Jakob E.
 

Fabio said


I have to say I love this little OEP bastards as line input and also as mic inputs! I´m not using on 1176 but on What compressor, COLOR!

This is great to know fabio! Exactly what i'm looking for in my 'Whats', i'm hoping that the 2520's in these are gonna give me some truly 'character' comps

Cheers

Jim
 
thanks gyraf

i thought i was probably being a naughty boy using the mic input trannie on the 1176 output, and what you say about core saturation certainly fits with the tone. at first i thought i dug the sound.

i'm thinking about some of the edcor trannies recommended in the LA2A threads - http://www.edcorusa.com/transformers/wsm/wsm.htm
any thoughts on using these as alternatives?

chris.
 
[quote author="Norbert Wilkins"]I was in Maplin today trying to get the correct resistors for my mini synth project (does no-one in there know how to read the colour codes?) and I noticed that they feature OEP audio transformers in their current catalogue, listed as NEW items. Unfortunately, being Maplin, they don't give the manufacturers codes.

http://www.maplin.co.uk/Search.aspx?criteria=n81cc&doy=27m1&source=15

Product code N81CC appears to be an A262A2E, but the 1+1:1+1 stat seems to indicate that p/c N82CC is in fact an A262A7E. It would appear that Maplin are being frustratingly eclectic in their product selection once again. Why they can't just stock the whole range like everyone else is beyond me.[/quote]

Yeah - it's frustrating - I contacted them about a month ago asking if they would add A262A3E to range. Maybe if a lot of forum members requested it they may stock. REASON! - look at the break price on 10 of the other models. 10 off screening cans cheapest at canford. I also contacted OEP direct and they would sell me 50 minimum already canned and they worked out same as buying 10 from maplin with 10 cans from canford!
 
[quote author="peterc"]We have 3 channels of OEP & 1 of Lundahl, & the Lundahl chan is the least used. I have not heard a loss of high end, but there is definitely more "vibe" using the OEP's.

I also was hesitant about the OEP / Lundahl choice, but I love that unit.

Peter[/quote]

Are you talking about IN & OUTput... BOTH?

- or just output?

I'm getting ready to build 2 units, mainly going to be using them on unbalanced insert jacks... Do you think I'd be better off with NO input tranny for this situation :?:

I'm not sure what the input tranny wants to see when it comes to impedence but I'm pretty sure the unbalanced inserts I'll be using are around 10k.

Thanks,
Kevin
 
Ours had only output transformers. I thought the OEP sound suited the "crunchiness" of the cct, the Lundahls for me did not add much colour, which is what we were looking for.

Not sure how the inserts would work, we ran ours in an input string.

Peter
 
i'm running OEP outputs on one pair, and OEP inputs and outputs on another pair.

i gotta say - the units with OEP trannie i/o are stunning. smoother than the output only units, and lovely tone whether treating them nice or overdriving the shit out of the inputs.
i don't think i need to try the lundahls - everyone says they're so clean . . . too clean?

on the basis of the two trannie i/o units, i'm planning on modding the electrically balanced input units to be switchable from electric in to trannie in (using edcor trannies, i thought - for a bit of extra fun and flavour).

here in melbourne, trannies are usually six foot tall, wearing wigs and skirts and makeup and answering to the name "craig" or "verity".
but that's all good.

:)

chris.
 
if you use the oep you have to alter the value of the 1k resitor between "+" and "-" after the transformer, otherwise the frequency range looks like an eq :)
then you can make serious comparisons between lundahl and oep
 
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