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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: tiberius]
      #1013203 - 12/10/12 09:36 AM
Quote tiberius:

When are the results out?




Yesterday... HERE

H

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Hugh RobjohnsAdministrator
SOS Technical Editor


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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013205 - 12/10/12 09:39 AM
Quote Exalted Wombat:

My instinct tells me there's no particular reason an expensive box's grunge should sound more desirable than a cheaper one's, but it would be fun to find out!




It will certainly be interesting... and I'm sure there are significant differences. I guess it depends where the 'grunge' comes from.

Transformer saturation will sound very different to valve stage saturation, and different transformers and valves behave differently too. Discrete transistors do something else again, as do ICs... the latter generally not going into overdrive in a very nice way at all unless a lot of clever circuit design is employed.

So generally, the more expensive products, with more elaborate circuit design, behave in a more musical way when pushed... at least, that's my experience.

Hugh

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James PerrettModerator



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Mattyy]
      #1013208 - 12/10/12 09:50 AM
Quote Mattyy:

What other magazine would do this?




The only other similar comparison that I remember was in Studio Sound in the early '90's where they tested complete mixer channels. I seem to remember the budget Studiomaster channel doing very well against its more expensive counterparts.

I really miss Studio Sound although I haven't picked up a subscription to its successor, Resolution as I don't have so much time for magazine reading these days.

James.

--------------------
JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.net


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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013225 - 12/10/12 10:51 AM
Quote Hugh Robjohns:

Quote Exalted Wombat:

My instinct tells me there's no particular reason an expensive box's grunge should sound more desirable than a cheaper one's, but it would be fun to find out!




It will certainly be interesting... and I'm sure there are significant differences. I guess it depends where the 'grunge' comes from.

Transformer saturation will sound very different to valve stage saturation, and different transformers and valves behave differently too. Discrete transistors do something else again, as do ICs... the latter generally not going into overdrive in a very nice way at all unless a lot of clever circuit design is employed.

So generally, the more expensive products, with more elaborate circuit design, behave in a more musical way when pushed... at least, that's my experience.

Hugh




You see my point though? It was a lot of people's "experience" that different preamps, used in their linear range, sounded a lot different. Until this week, when you actually tested it.

This is exciting! Like the Archbishop of Canterbury calling up Richard Dawkins and saying "..er...just run that past me again, will you...?" Strictly evidenced-based choice of equipment! In with asprin and Viagra, out with homeopathy and acupuncture. "Yes, I KNOW you have "experience" they work. Now test it!"


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013260 - 12/10/12 12:34 PM
Quote Exalted Wombat:

You see my point though? It was a lot of people's "experience" that different preamps, used in their linear range, sounded a lot different. Until this week, when you actually tested it.




Presumption and wholesale swallowing of urban myths, rather than 'experience'! Those with real first-hand 'experience' knew fully well what the outcome would be.

While I own and use regularly several recognisably high-end preamps (GML, SSL, Focusrite ISA, AEA,), I'm just as happy to use more modest preamps when more convenient or appropriate, including SADiE, Sound Devices, Mackie and Yamaha. I've made dozens of high-quality recordings using Mackie preamps and know fully well that the preamp really isn't the quality-limiting factor in 99% of situations.

Quote:

This is exciting!




It's certainly refreshing

Quote:

"Yes, I KNOW you have "experience" they work. Now test it!"




All in good time...

H

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tiberius



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013281 - 12/10/12 01:57 PM
That is great news - my favourite preamp is pretty damn cheap.
I'm glad I don't have to drop a ton of money to get a great sound.


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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013409 - 13/10/12 12:25 PM
Quote Hugh Robjohns:

While I own and use regularly several recognisably high-end preamps (GML, SSL, Focusrite ISA, AEA,),




You're into pushing levels past the linear zone then? What sort of source would prompt you to choose one of these, rather than just "what's on the board"?


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013414 - 13/10/12 12:48 PM
Quote Exalted Wombat:

You're into pushing levels past the linear zone then?




No, only very rarely. Most of the music I work with requires the utmost transparency and linearity.

Quote:

What sort of source would prompt you to choose one of these, rather than just "what's on the board"?




I often do use 'what's on the board' -- as I already explained. Mackie, SADiE, Yamaha etc...

But I use the AEA primarily for its very high imput impedance and huge gain range that suits ribbon mics very well. The GML and Focusrite also both provide a lot more clean and quiet gain than any console preamp I have available, so I tend to use those if I'm using low output mics, working with quiet sources, or at large source-mic distances -- all fairly common situations in the classical and choral recording that I tend to do mostly.

The SSL is used mostly for colour on occasions when that is appropriate.

But fundamentally, these are all well made, well designed, products with professional reliability, features, ergonomics and support. And that means I can trust them and not have any concerns that they will be a weak link when I'm recording on location miles from any backup facilities!

H

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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013444 - 13/10/12 03:24 PM
Quote Hugh Robjohns:


But fundamentally, these are all well made, well designed, products with professional reliability, features, ergonomics and support. And that means I can trust them and not have any concerns that they will be a weak link when I'm recording on location miles from any backup facilities!





Yes those preamps on the Mackie boards fail all the time! Lord knows why, there's so few components in them :-)

I'm sure I've recently seen another report that small-market equipment was often much less reliable. Not sure if it was anecdote or evidence-based.


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013447 - 13/10/12 03:37 PM
Quote Exalted Wombat:

Yes those preamps on the Mackie boards fail all the time! Lord knows why, there's so few components in them :-)




Very amusing -- you're on fire with this one aren't you!

Fortunately, I've never had a problem with my 1402VLZpro... so far... but I'm sure you'll recall the many threads we've had in this very forum about relatively common failures in many Mackie desks caused, typically, by corroding wire links between boards.

Thankfully, modern production processes have improved the reliability of all forms of modern electronics enormously over the last few decades. Nevertheless, I would still rate reliability as one of the important advantages that justifies -- to me -- the cost of some of the preamps I choose to own and use.

hugh

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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013450 - 13/10/12 03:49 PM
Quote Hugh Robjohns:

Very amusing -- you're on fire with this one aren't you!




I don't suppose we'll actually get an owner of an expensive preamp to come out with: "Yes, I was taken for a ride there, wasn't I!" But it's fun trying :-)


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Bob Bickerton
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013471 - 13/10/12 06:06 PM
Quote Exalted Wombat:

Quote Hugh Robjohns:

Very amusing -- you're on fire with this one aren't you!




I don't suppose we'll actually get an owner of an expensive preamp to come out with: "Yes, I was taken for a ride there, wasn't I!" But it's fun trying :-)




I'd almost fall into that category, but don't particularly want to winge about it here........

Bob

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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013479 - 13/10/12 07:13 PM
Quote Exalted Wombat:

Quote Hugh Robjohns:

Very amusing -- you're on fire with this one aren't you!




I don't suppose we'll actually get an owner of an expensive preamp to come out with: "Yes, I was taken for a ride there, wasn't I!" But it's fun trying :-)




The concept of value for money is a largely personal one. I couldn't justify buying a grace design m201, but I can understand why others can. I can justify buying the preamps I have because they all do things I value in ways I like. And I enjoy using them, and they meet my needs. That's enough for me.

H

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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013516 - 13/10/12 11:40 PM
Quote Hugh Robjohns:

The concept of value for money is a largely personal one.




But we've made a good start towards making it more objective! Let's not back-pedal.

Really, this preamp test (along with the "you don't really need a seperate master clock" one) are the most encouraging reports I've seen in any gear mag for a long time.


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DC-Choppah



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013523 - 14/10/12 02:13 AM
Quote Exalted Wombat:

... I would still rate reliability as one of the important advantages that justifies -- to me -- the cost of some of the preamps I choose to own and use.

hugh




Oh man. I love the sound of my Mackie VLZs and your test tells me they sound pretty much the same as others. But I hate the fact that all of the pots on my mixing board need to be professionally cleaned often (which requires a full disassemble). Sometimes I get a complete dropout and go wiggle a knob to find that the aux send, or something has flaked on out me.

Since you have established sonic equivalence, would love to know which board stays cleanest over time with real world use. That will be my key parameter when I upgrade I think.

Edited by DC-Choppah (14/10/12 02:18 AM)


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ef37a



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Re: Preamp comparison in SOS October 2012: your views! new [Re: DC-Choppah]
      #1013525 - 14/10/12 07:21 AM
'Twas ever thus CD-C'.
Decent pots and switches cost!
Farnell list the Grayhill 16way single pole at £22.48. With VAT that is more than 1/2 the price of a quite decent 2 mic input mixer!

Then there are cheap components, even ICs about. I know of the first production run of a product where several NE5532s"blew up"! My own experience with a Behringer BCA2000 was that 12 months in the chip on chan 1 mic amp died. SM tech so I put an NE on a postage stamp sized bit of stripboard and wired it in. Worked fine then a few months later chan 2 went down and I can't be arsed! I now have a ZED10 and the Berry gathers dust. Shame because in many way that AI has never been surpassed for facilities at any price that I have seen.

"There is always someone who can make a thing a little worse for a little less" (attrib Slugger Sugar?).

Dave.


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013543 - 14/10/12 09:19 AM
Quote Exalted Wombat:

But we've made a good start towards making it more objective! Let's not back-pedal.




No back pedalling, but you seem to be pushing in a different direction entirely.

This comparison was not about saying "all preamps are the same", or that "a cheap one is every bit as good as an expensive one" -- which seems to be the thrust of your comments.

What it was trying to show was that the sound quality of cheaper preamps -- when used to provide moderate levels of clean gain -- is virtually indistinguishable by most people from very expensive models. A budget preamp needn't be the weakest link in any recording chain, because the technology has improved radically over the last decade or so.

That's it. Something that will hopefully inspire people to hone their skills rather than blame the equipment!

But, only someone with a fetish for wearing blinkers and being deliberately contrary would try to deny that spending more money on a preamp brings worthwhile benefits. How worthwhile, how relevant, or how cost-effective becomes a matter of personal judgement, of course.

For example, I really don't like the way virtually all budget preamps end up with most of the gain range squashed into the last ten degrees of rotation of the gain knob. I will gladly pay more for a preamp designed in a better way so that it has much better ergonomics. You, perhaps, might not mind that at all.... Different personal preferences and judgements...

Quote:

Really, this preamp test (along with the "you don't really need a seperate master clock" one) are the most encouraging reports I've seen in any gear mag for a long time.




I'm pleased you appreciate our efforts. There are more things to debunk and other ways we want to help readers re-focus their attention on the things that really matter.

H

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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013553 - 14/10/12 10:53 AM
Quote Hugh Robjohns:

But, only someone with a fetish for wearing blinkers and being deliberately contrary would try to deny that spending more money on a preamp brings worthwhile benefits. How worthwhile, how relevant, or how cost-effective becomes a matter of personal judgement, of course.




A certainty that spending more money MUST bring worthwhile benefits may be the blinkers!

Come on, you've done a great job. Don't get scared now and hedge it with "of course we all know the expensive ones are REALLY better, even though they sound much the same". If they're better, show us - with blind testing.

Remember the old joke in the early(ish) days of computing? Set up a company, stick a couple of floppies and a CPU in a box, add a flashy model name and an even flashier price tag. The Post Office will buy one, for "evaluation". That'll do!


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Guy Johnson



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013555 - 14/10/12 11:10 AM
Another plus for the Mackie amps is that we heard them through another stage of electronics, namely the Art box.

--------------------
Facebok Page for acoustic music PA-ing in smaller venues


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Exalted Wombat



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Guy Johnson]
      #1013560 - 14/10/12 12:07 PM
PLEASE don't start listing all the loopholes in the preamps test! It was such a satisfying result :-)


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Exalted Wombat]
      #1013571 - 14/10/12 01:09 PM
Quote Exalted Wombat:

A certainty that spending more money MUST bring worthwhile benefits may be the blinkers!




It may be... but I didn't say MUST

Quote:

If they're better, show us - with blind testing.




You can't assess build quality, reliability, ergonomics, flexibility, control linearity, serviceability, or support through blind testing...

I understand what you're digging at, but things aren't anywhere near as black and white as you make out. What we've done here is hopefully to enhance the contrast and saturation a bit, but it's still a colour picture!

H

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DAGGILARR



Joined: 22/09/10
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013593 - 14/10/12 03:43 PM
Quote Hugh Robjohns:



For example, I really don't like the way virtually all budget preamps end up with most of the gain range squashed into the last ten degrees of rotation of the gain knob.




H




Where would you say the price point begins where this is no longer the case ? I have a Focusrite Pro24, OK preamps but this suffers from this gain range squashing you speak of.

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ef37a



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Re: Preamp comparison in SOS October 2012: your views! new [Re: DAGGILARR]
      #1013597 - 14/10/12 04:14 PM
Unfortunately Daggilarr this is a very difficult problem to solve if you want a gain more than about 50dB and insist on a continuous control.
A far better solution is stepped gains from a rotary switch but even if the cheapest possible switch was employed you still need about a dozen fixed resistors, some of way out of series values and not least the space to fit it all!

Some preamps used a relay to switch in another set of resistors. You could use a twin gang pot with different track values and switch them over. Or a pot with a "pull boost" to kick in another 15dB or so?

This is of course where the £1000+ boys score. They can use relay ladder attenuators and software control. But since us poor folk only really need the highest gains for dynamics and ribbons, invest in a Cloudlifter and keep the mixer/AI gains low? I actually solved the problem on my Fast track pro but only because it has inserts. I built an NE5532 20dB booster to put in the inserts and thus I could keep the pro's gain pots at about mid point. (no need now, have the ZED10 and Ka6)

But of course this all C.O.S.T.S!
Dave.


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vinyl_junkie
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013607 - 14/10/12 04:55 PM
Couldn't they just use a linear taper pot instead of a logarithmic pot?

Edited by vinyl_junkie (14/10/12 04:55 PM)


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: vinyl_junkie]
      #1013612 - 14/10/12 05:25 PM
Nope. Most preamp designs actually need a reverse-log pot, and even then control law linearity is ALWAYS a problem.

H

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mjfe2



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Re: Preamp comparison in SOS October 2012: your views! new [Re: DAGGILARR]
      #1013615 - 14/10/12 06:00 PM
Quote DAGGILARR:

Quote Hugh Robjohns:

For example, I really don't like the way virtually all budget preamps end up with most of the gain range squashed into the last ten degrees of rotation of the gain knob.






Where would you say the price point begins where this is no longer the case ? I have a Focusrite Pro24, OK preamps but this suffers from this gain range squashing you speak of.




I was surprised when I got my RME Octamic recently that even this does it. But there's no way I can afford a Micstasy just to get stepped gain controls. I'm still pleased with my purchase because it feels solid and I know the A/D side with RME is particularly solid.


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dmills



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013617 - 14/10/12 06:08 PM
And reverse log pots are like rocking horse droppings in small quantities (And end resistance can be a big issue, as can the huge DC blocking cap needed to retain a reasonable 3dB point at only tens of ohms or resistance)......

You could probably do something like start with a fixed 10 or 20dB, then put a VCA in the feedback loop of an opamp to provide dB linear gain from there out, but then your noise rises and your technical specs are worse.... And again,it all costs!

Other ways to skin it include using a TI PGA2500 or a THAT 5170/5171 programmable gain mic preamp chip with a small micro and optical encoder, but that rather limits your choice of architecture, and again it all costs in both development time and BOM....

Doing it right is easy, doing it cheap is easy, pulling both off in the same product is what separates the men from the boys.

Regards, Dan.

--------------------
Audiophiles use phono leads because they are unbalanced people!


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Mike101
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013662 - 15/10/12 12:44 AM
This was an excellent article. The closest thing to a placebo control double blinded scientific study. I first listened to the files on my iPad with Bose headphones and then through a Benchmark converter with Sennheiser HD 600 headphones and I was unable to hear any significant variations within a microphone series except for the Brauner H which sounded like the mics had been moved giving a wider stereo separation. Clearly in todays high level of quality across the spectrum, the preamp contributes little and Boutique gear is unnecessary.
The most important points in the sound chain are were mechanical energy is converted to electrical (i.e. the mic) and at the other end where electrical energy is converted back to mechanical (i.e. the speaker) Microphone design and quality, placement, acoustics in the recording and listening environments and speaker design and quality are where to spend your money. In my earlier days we also had the conversion of electrical energy into magnetic flux and back in addition to the conversion of electrical energy into mechanical and back again in a vinyl record. Today the converter is the next most important step when electrical energy is converted into numbers and back again. Regardless, most end users are listening through ipod converters and amps and ear buds or low quality speakers which still sound better than expensive equipment in the 60's. Today all I record is classical music and what matters is the hall the mics and mic placement.
It really all comes down to material, talented musicians, engineers and producers; not some imagined difference between $2000 preamps.


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Phil Reynolds



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013664 - 15/10/12 01:21 AM
scuttles in/

I'm in the process of building a mic made from an old phone and half a pair of broken headphones for people to shout down. Don't think all the preamps in the world are gonna make a difference there...

/scuttles out



--------------------
"We knocked on the doors of Hell's darker chambers..." But no-one answered, so we went to the pub instead.


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James PerrettModerator



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Re: Preamp comparison in SOS October 2012: your views! new [Re: ef37a]
      #1013685 - 15/10/12 09:42 AM
Quote ef37a:

Unfortunately Daggilarr this is a very difficult problem to solve if you want a gain more than about 50dB and insist on a continuous control.





It all started when Mackie introduced their padless preamp. Before then people were happy with a sensible gain range and an attenuator switch to cope with the loudest sources.

James.

--------------------
JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.net


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Guy Johnson



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013712 - 15/10/12 12:01 PM



This arrangement works well on my fave desk. The line switch also acts as a pad when using the mic input, so you get two pads, both of the same value (not stated).

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ef37a



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Guy Johnson]
      #1013743 - 15/10/12 01:30 PM
Nice one Guy but I hope there are a couple of blocking caps we can't see to keep spook juice off the line input?

Dave.


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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Guy Johnson]
      #1013765 - 15/10/12 02:33 PM
Quote Guy Johnson:

This arrangement works well on my fave desk. The line switch also acts as a pad when using the mic input, so you get two pads, both of the same value (not stated).




Looks a pretty standard arangement to me. Don't quite understand the comment about the line input switch, though. The implication is that the line input is actually in parallel with the mic input (post phantom power connection, obviously).

H

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Guy Johnson



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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013793 - 15/10/12 04:49 PM



Eek! Where to stop with the diagramme? Anyway, here's more of it .. with caps!

The effect of the line switch (apart from routing from the line trs) is as a pad, when using the mic input. So with the line switch and the one labeled pad, one can stick rather silly voltages in, though I've never needed the double-pad scenario!

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Hugh RobjohnsAdministrator
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Guy Johnson]
      #1013803 - 15/10/12 05:44 PM
Quote Guy Johnson:

The effect of the line switch (apart from routing from the line trs) is as a pad, when using the mic input. So with the line switch and the one labeled pad, one can stick rather silly voltages in, though I've never needed the double-pad scenario!




Yes... normally a line 'switch' does exactly that -- switches away from the mic input and passes only the line signal. You're saying it still passes the mic signal...

So from that I have to presume that both the mic and line sockets are wired in parallel and routed through the same switch which acts, as you describe, as an additional pad, before routing the now mic-level signal to the mic preamp. Your diagram does show some rather ambiguous normalled connections between the mic and line sockets.

Could it be that the mic signal is routed through the line socket normalling if nothing is plugged in, and thus appears as a very well attenuated signal if line mode is selected with only a mic signal connected? I can see some sense in that facility... althoguh I'd have thought the pad button was no longer functional in that mode

H


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Edited by Hugh Robjohns (15/10/12 05:50 PM)


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ar316



Joined: 03/12/08
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Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013838 - 15/10/12 09:17 PM
It looks like I'll be pulling the trigger on the Digital MPA II I've been debating purchasing.

Hugh, were the stock tubes used in the MPA II for this shoot-out?

Edited by ar316 (15/10/12 09:19 PM)


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Persuazion



Joined: 29/10/05
Posts: 1619
Loc: Scotland
Re: Preamp comparison in SOS October 2012: your views! new [Re: Hugh Robjohns]
      #1013845 - 15/10/12 10:17 PM
Even my trusted Audient desk (8024) pres suffer from a gain jump up top as well as noise with some ribbons. More than enough for me to make an obvious decision and go to my DAV pres for distant ribbons and the like. And in fact would get a bit 'jumpy' if I didn't have the DAVs to hand. And I really wouldn't like to use my Saffire 26i/o pres on a ribbon mic at the back of a church (fair enough a ribbon might not be a good choice here but you get the gist..)

This article hasn't really altered my views on nice preamps at all. I know I will be buying some more fancy, expensive preamps in the future, I just have my eye on preamps with clear differences - Audient Black with HMX, Thermionic Rooster, Chandler Germanium, LA 610 (the 610 has clear character for me when pushed). I know most of these are more than just preamps and so not exactly what we're talking about.

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Sam Inglis
SOS Features Editor


Joined: 15/12/00
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Re: Preamp comparison in SOS October 2012: your views! new [Re: ar316]
      #1013885 - 16/10/12 08:23 AM
Quote ar316:

were the stock tubes used in the MPA II for this shoot-out?




Yes -- I don't think it had even been out of the box before.


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Goddard



Joined: 04/04/12
Posts: 949
Re: Preamp comparison in SOS October 2012: your views! new [Re: Sam Inglis]
      #1013907 - 16/10/12 10:04 AM
Quote Sam Inglis:

Quote ar316:

were the stock tubes used in the MPA II for this shoot-out?




Yes -- I don't think it had even been out of the box before.




I may be mistaken, but afaik the ART tube pres (all?) use a solid state input stage before the signal ever gets to the tube "drive" stage anyway. What interests me is the input impedance adjustability.


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Matt Houghton
SOS Reviews Editor


Joined: 08/08/07
Posts: 596
Re: Preamp comparison in SOS October 2012: your views! new [Re: Goddard]
      #1013915 - 16/10/12 10:34 AM
Quote Goddard:

What interests me is the input impedance adjustability.




Yes, I know what you mean. In my own experience, some dynamics seem to be more audibly affected by this than others. The SM57 for example. If you're not aware of it, the Magneto Labs VariOhm might be of interest.

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