XLR Attenuator for hot preamp signals

[vanderlae]

Reading Rob's article in AT mag about pads last night reminded me that I needed to find a solution myself.

My signal coming out from my Neve 1073DPD is too hot when going into my interface - often I have to keep the gain very low and trim all the way down just to get a workable input. Suffice to say I'm not getting the best out of my Neve therefore.

Rather than just to attenuate the signal coming IN to the preamp from the microphone with a (say) XLR pad, I thought it makes more sense to attenuate the 'finished' signal coming out from the preamp before it hits the interface. That way I can dial in the gain that I want whilst not having the actual input signal lowered. In other words, I'd prefer to keep the original signal going in 100% and attenuate the output before it hits the interface.

My question is can you simply use the XLR pads in between the preamp's output and the interface? I've found a couple on ebay which I'd like to know if they'll do the job that I'm talking about:

1) http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 1009wt_934

2) http://www.ebay.com.au/itm/SHURE-A15AS- ... 2672wt_907

Thanks,
Dave

[Ben M]

My question is can you simply use the XLR pads in between the preamp's output and the interface?

Hi Dave
I would say a big yes to that.

[AnthonyMF]

I've done this before, one studio I like has an older version of a TLA pre/eq which lacks an output pot, so when I want to drive it a bit I use a pad and it works great. That Shure variable pad looks pretty cool. 20dB was plenty for me, maybe even too much, the HOSA might be overkill but the 15/20/25 option could be perfect.

Edit: Urk! Aside from the price!

[Chinagraf]

Pretty easy to wire your own if you are so inclined, just google H pad design.

[Chris H]

iI use them to pad the outputs of my Byer preamps which are +8. I have two each of 10 dB and 20dB inline pads, no sonic degradation. As a norm, every 6 month, or so I spray all my XLR , mic and other connectors with deoxit and give them a good working over, plugging them in and out to make sure the contact is clean. I also get the eraser onto the pin connectors of my optro console...... i like em shiny clean.

[chribble]

Check your interface, if you can switch between +4 and -10 etc maybe that can make a difference without having to buy anything

[Kurt]

Karma Mics do one as well, but they're apparently out of stock.

http://www.karmamics.com/shop/Karma-In- ... e-Pad.html

I actually want something very similar but with a hi-pass built in too.

[Junction]

That seems odd, most balanced output rack gear these days operate at a nominal +4dBu out .... then is your interface either unbalanced in (-10dBu) or is set to -10 in as Chris suggested? If so then you will be 14dB hot.

As Andy suggested you could knock up a H Pad (5 resistors), the perfect passive solution, with a bit of care I have managed to squeeze these inside an XLR connector, male XLR's generally seem to have a bit more room inside the connector for a pad.

.... then again, that Neve pre can push out peaks of up to +26dBu, wheras some interfaces may peak at something less than +20dBu, does pulling the gain of the pre back a bit not get you there?

[vanderlae]

does pulling the gain of the pre back a bit not get you there?

Yes, but it isn't the there I am after. Usually. Backing the gain off as low as it oftentimes is lacks oomph and depth, so the idea is to get more range out of the gain. Otherwise my Neve may as well be anything.

Interface is set the way it should, so it's just the hot signal I'm dealing with that makes it clip. Pad gets the thumbs up it seems. I neither have a soldering iron or patience to relearn to solder, so ebay looks to be my hero at the moment.

Some say there is a 'sweet spot' on the 1073s, well maybe with a pad I'll find it! I actually miss my Chandler TG2 that I sold (here) right about now...*sighs*

Cheers
Dave

[Hookemeister]

Hi Dave

My guess is that the front end of your interface doesn't have the same headroom as the 1073.

If your interface is set to +4 but it only has a maximum of 14 - 20db of headroom, which is not uncommon these days in semi pro gear, and the 1073 has 26db of headroom, then you're going to have problems.

First thing you need to do is find out what the specifications of your interface are.

Second work out the difference in headroom and get a pad that will give that amount of attenuation.
Of course you will sacrifice some signal to noise ratio as a result.

Alternatively you could take the digital output of the 1073 and run it into the interface digital in. As long as AMS have the convertor placed after the output transformer then you should retain the Neve sound.

To get that Neve magic you really need to be running that 1073 module at +4 out.

Maybe it's time to invest in a better interface. Really your interface should be able to match the specs of the Neve.

One last possibility... maybe there's a problem with the 1073. See if you can get into another studio and try it with a pro quality interface just to confirm that everythings OK with the Neve.

Hope this helps

Greg

[rick]

greg is perzactly right
to get the very best out of a classic neve pre you need to run it the way it was designed

that is your are aiming to get the output of the neve on any signal to peak at ovu ( +4dbm)
have you got a vu meter in circuit somewhere ...? to check

what this means is unless your interface is truely only looking for a domestic low level -10 signal

that you must be hitting the neve too hard - sure i get it your looking for a sound from the pre ... yadda yadda

but the sound is at 0vu .. you goning to have to trust me on this i have tried every other way to skin the cat
but o is best - not +8+10+16 or whatever you have coming out of the box

the gain stages in a classic neve pre are pretty specific in the way they are set up
they are meant to have a fine gain control attached at that is meant to fine trim the 5 or so db to the top of signal or attn it down to infinity but the game is always set it so its hits ovu and have the fine trim doing as close to nothing as you can


you sure can put a pad at the output if your interface is -10
but if its not
it might be time to scratch your head a bit further in regard to gain staging the beast me thinks

[rick]

oh yes if you only using the first or 2nd stop of the neve pre gain
0 -5- 10
thats about right for drums and elec guitars

-15-20 for classic tube mics ( u47 ) on vocals

-25-35-40 for acoustic gtr with standard mics

all bets are off after that - you have another 30-40 db of neve preamp gain to play with

i dont think i ever head there on a neve - well not after i learnt its not so great in that range

if your in that -40 -50 -70 range its probably time to look at a different pre amp
or those little ribbon mic booster pre- pres...
or a different microphone

thats not were neves are doing their best stuff - some might even say they are noisy in that gain range

personally i would ask wtf your doing there ...

the 30 db or so from a 1272 is all you ever need to get "that" in your face larger then life sound i reckon

[vanderlae]

sheesh, didn't know I had to bring the bat and fend of second-gueses, but looks like I must... ; )

I'm running the Neve straight into a 003R, set at +4. Now, I know it's not HD, but I wouldn't at all call it pro-sumer level gear. I often run the mix or stems through a HEDD192 also, not to get off topic, but I love the HEDD. My room is predominantly a composing suite so at this point at least, a HD wouldn't give me a huge advantage. As for what mics I'm putting through it - as it was mentioned - they are U87, Coles, Royer, 57, KM84 and that's about it.

Rick I'm not aiming for an unnecessarily gain-drenched signal, no, and I've usually got it quite low. Gain usually swinging between 30 (is that - 30?) or 40. Trim usually at -10 to -5.

I did recently get an AES to 003 adapter from VK to run the Neve digitally into the 003, so maybe I'll try that before anything else and see if it improves. I've never done it before and hopefully it won't introduce latency when tracking.

cheers

[rob]

the variable pad mentioned in the AT article using a dual gang 1K log pot can be a very handy widget to have around. Put it in a small diecast box with XLR in and out and use to taste.

[rick]

Ok presuming apples are apples and the new neves are the same as the old neves

your still running the input gain hotter the i would assume you need
but obviously that is so wide open as a statement ...
but i am surprised that your in the- 40db range with those mics with normal music type sounds
of coarse if the trim is - 10 then your not in working in the 40 db range but technically you still in it electronically

but the same principle applies and sorry if its looking more arguementive then it needs be
the output of your neve should be hitting 0vu on vu meters pretty much always thats where it should run

which should be way under the peak level of the oo3
like at least to 6-14db under ...depending on what the sound is

but if i understand what your saying for some reason it is not that lower level
its too hot and popping the ceiling of the converters and that is your need for attn ?

i guess we are trying to help out but sometimes on the internet it can look like an inquestion it shouldnt get that way around here

sorry if it looks like we arent helping

my feeling is a pad will solve your issue

but you still have an underlying problem somewhere
it just should not be that hot ! coming out of the neve
grab a vu meter from somewhere and report back
it could be the gain structure of the new neve stuff isnt the same as the old stuff
but i dont think so
i am curious