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preamps?

i was woundering is using a preamp essenstial? whats the difference between pluging a mic directly to a board and using a pre? its been jogging my mind. everyone always says you gotta use a pre. i agree but would it accually make what your micing sound better?

Comments

ouzo77 Sun, 03/19/2006 - 06:30
0db wrote: 1) You should check first your instrument before make any investment. Check defective solders, dusty potentiometers, etc.

2) To avoid impedance coupling problems, i strongly recommend that you connect your guitar to a amp, and mic it.

3) For the bass, use a DI box.

4) I have not read reviews of any of those pre´s, neither used it. I think you should check other things first, like broken cables, proper grounding.

Just my opinion.

Good Luck

Juan

thanks for your reply.

the noise definitely comes from the input of the audio interface, cause it's there even when no cable is plugged in. usually you don't hear the noise at all, cause it is very low, only when i run it through my software guitar amp it gets amplified. i hope i can reduce it by sending more input into the interface. with more input i can reduce the gain in my amp software, which should result in less amplified noise. well that's my theory.
next time i go to my computer i will try reducing the gain without the guitar plugged in. i should here if it works this way or not.

ouzo77 Sun, 03/19/2006 - 11:22
i have an audiotrak inca88 - 8 ins and 8 outs in 16bit/44.1khz. not a pro interface, but then again, i'm not a pro. i'm recording with logic 5.5 on a windows pc.
like i said, usually the noise floor isn't audible, only when sending it through a guitar amp vst or when compressing heavily. but who would like to do that?

that's why i want to get a preamp. and since i can't afford an expensive one, and wouldn't buy one if i had the money, anyway, i wanted some recommendations on some decent ones around 100$us.

i can kill the noise when sending the signal first through a denoiser, and since i put the distorsion on afterwards, there's no audible change in the overall sound. but the sound is delayed a lot, which i have to compensate.

so i hope to avoid this denoising by using a preamp.

Kev Sun, 03/19/2006 - 14:49
audiotrak inca88 is now discontinued ... yes ?
logic 5.5 on a windows pc ... very old ?

I'm getting the picture

http://www.audiotrak.net/download/MANUAL/INCA88/AT_inca88manual.pdf

it does have SPDF
it does seem to have two mic-amps

I suggest a simple DI box which you should own anyway

then look at page 41 about the Mic-Preamp
1. +20dB
When this button is engaged, the mic preamp will amplify the level of the input from the mic by
+20dB. The mic input level is less than the line input level, and this mic preamp needs to be on
when you use mics.
I still think you will need a mic-pre and this is a good thing anyway cos as with the DI Box you will use it long into the future IF you buy something sensible

and read up on the various modes

you need to get the Guitar up to nominal line level which for this unit seems to b -10dBv ??

page 26
3. Analog outputs 1~8
The Analog Outputs of the INCA88 are the main outputs to send out the signal processed by the
INCA88. The INCA88 provides 8 analog outputs for the convenience of users. Outputs are –
10dBV unbalanced analog using a 1/4” phone jack. You can connect to an amp or a mixer.

I haven't read it all yet ... probably have run out of time right now

ouzo77 Mon, 03/20/2006 - 05:31
well, thanks for researching this, but i know what my interface can do.
so you think a di box should be enough for guitar and bass?
i don't need an extra mic preamp, cause the mic i'm using for vocals comes with a tube preamp. i just need something to raise the gain of my guitar output/input.

ouzo77 Mon, 03/20/2006 - 10:50
i am sure!

i know that i can raise the input for mics on channel 1 and 3 by 20db. but this is way too much for my guitar.

but i don't know what the outputs have to do with my input level...?

i'm using THE T.BONE SCT700 microphone, which goes into a tube preamp that came with the mic. the output of the mic is pretty high, so i don't have to use the +20db switch.

i know now for sure, because i've tried it, that the noise in my guitar amp software comes from the input, which i have to raise about 9db to get a decent guitar level (not for my bass, which has enough output by far!). with the input on 0db the noise is gone.

i just need something to raise my guitar level before going into my audio interface. whether it's a preamp or di box, i don't care, as long as it works!

so again any suggestions on the preamps i mentioned before or any other, or if a di box will do the trick, are very welcome!

thank you.

Kev Mon, 03/20/2006 - 12:20
ouzo77 wrote: i am sure!
sorry
I don't think you do know what the inside workings of your interface are
... the termination impedances and headroom/noise-floor issues

ouzo77 wrote: i know that i can raise the input for mics on channel 1 and 3 by 20db. but this is way too much for my guitar.
20 dB gain is way too much for a guitar ? ... wot ?

ouzo77 wrote: but i don't know what the outputs have to do with my input level...?
the outputs were mentioned only because it had reference to the possible overall spec for the interface
-10dBV

ouzo77 wrote: i'm using THE T.BONE SCT700 microphone, which goes into a tube preamp that came with the mic. the output of the mic is pretty high, so i don't have to use the +20db switch.
I don't think it comes with a mic-preamp
it is a power supply

this unit can probably output a healthy level
this coupled with the fact that the interface is -10dBV
it doesn't suprise me that you can record with the +20dB og gain for some sources

ouzo77 wrote: ... with the input on 0db the noise is gone.
yes
you need to get the low level guitar output up to a nominal -10dBV

ouzo77 wrote: ... i just need something to raise my guitar level before going into my audio interface. whether it's a preamp or di box, i don't care, as long as it works!
since you don't care

try a Countryman DI box


followed by
an simple API styled mic-pre like say the ADK


if you can't afford that then you will find something from Behringer that will go some of the way


Guitar level and 1 meg ohm output
through DI box to give
Guitar level and 150 ohm ouptut (that makes it similar to mic level)
into Mic-pre with 150 to 300 ohm input
gained up to Line level of +4dBu / dBm and 600 ohm ouput
pad it down to -10dBV

if the mic-pre has an unbalanced -10dBV output you won't need the pad

you may get lucky with a simple DI box and the mic-pre in the interface only

ouzo77 Mon, 03/20/2006 - 13:32
Kev wrote: sorry
I don't think you do know what the inside workings of your interface are
... the termination impedances and headroom/noise-floor issues
i may not know nor really care what the technical aspects of my interface are, since i'm not an engineer, but i do know how it works, what or how much i can send in, and i know what's coming out. i'm working with this thing for over 3 years now.

20 dB gain is way too much for a guitar ? ... wot ?
you won't believe it, but i did try this for my guitar and all i got was too much signal. it would be clipping all the time. +9db are all i need. but you should know that i can't set the recording/input level lower than 0db. don't know if it's only with this interface or if it's common. logic will record what it gets from the interface. i can't set the rec level there, either. so 20db - too much input!

I don't think it comes with a mic-preamp
it is a power supply
it is a power supply, but it also sends the mic signal through the built-in tube, which is something like a pre-amplification, i think.
nevertheless the level and the sound are good enough.

ouzo77 wrote: ... with the input on 0db the noise is gone.
yes
you need to get the low level guitar output up to a nominal -10dBV
that's what i'm talking about. just need a little more input.

try a Countryman DI box

followed by
an simple API styled mic-pre like say the ADK

if you can't afford that then you will find something from Behringer that will go some of the way
looks good, but i'm afraid they're not in my budget.

i'll try a di first. i can borrow one. if that doesn't work i will try a preamp. maybe i can borrow one, too.

don't get me wrong, i really appreciate that you took your time to help, but i knew already where the problem was (low input - need more!!!), even though i didn't know the theoretical background. but i never liked theory, anyway :?

ecc83 Mon, 03/20/2006 - 13:45
pres versus board ip et al

This topic is doomed because people are mixing up two questions.
1) Can two bits of competantly designed gear with a cost ratio of 10:1 sound the same?

2) Is different the same as better (or worse) To 1) I say yes. There are only so many suitable ic's transistors ect you can make a preamp with , what you can't buy is a Name!
2) Easy, feed two different pres with a common signal, level match. and switch between the two. The one that sounds different from the original sound is wrong ( but you might prefer it!). Take two pieces of venerable, but loved recording gear, one semi-pro the other very pro. The Revox A77 tape r . This is still regarded as one of the best s/p machines ever made add the Nagra 5 portable the veritable workhorse of stage screen and radio ( till DAT). But look at their circuits! Bog standard, BC 109's 107's standard low gain H bias techniques but I bet many studios still think the world of them.The reason they sound ok is because they are good enough!

Kev Mon, 03/20/2006 - 14:45
Re: pres versus board ip et al

ecc83 wrote: This topic is doomed because people are mixing up two questions.
1) Can two bits of competantly designed gear with a cost ratio of 10:1 sound the same?
welcome ecc83
( an ecc83 could make a good guitar gain DI box thingy )

I'm not mixing up questions and have a very clear idea of the problems being faced

yes two pieces of gear can have a cost ratio of 10:1 and sound close for a given sound source
it may not be the brand name to cause the 10:1 ratio and may just be component choices
It CAN also just be about brand name

it is when the source becomes special or different that the expensive stuff can really shine
Ribbon mics and situations that demand 75dB of gain can set mic-pre apart

I build and repair gear and on my sites you can find inside pictures to many of the peices discussed on these forums

A simple DIY passive DI box using a 10k to 600ohm transformer can contain a Jensen (expensive) or a No Name (cheap)
Only you can decide which sounds better.
10k is still too low for a typical Strat style guitar

A equally simple FET or op-amp DI box can contain parts of varied values
The JLM DI Kit is only $28USD


it does have an opa2604 rather than a TL071 or 72
not that there is anything specifically wrong with a TL0
It uses the two opamps from a OPA2604 in Parallel so it can drive 200ohm loads. It has a 1Meg input impedance on the jack so the loading to the guitar pickup is the same as a Fender or Marshall Amp.

just fine for your Strat

StevenColbert Sat, 03/18/2006 - 03:44
scarface wrote: would it actually make what your mic sound better?
One word...
YES
All preamp's are small circuits, that add gain to the signal. And all companies make different designs to achive gain. So ALL preamp's sound different in one way or another.
If a preamp is made of $150 worth of electronic components then the sound will be cheap sounding and most likely not that warm.
However if you have a preamp that cost about $1500 (not including labor cost) It will be 10 times better IMHO.
And SHOULD sound way better than any of the cheaper designs that use lesser components and shortcuts to achive gain.

cheap parts= cheapest sound
good parts= good sound
best parts= best sound possible

moonbaby Sat, 03/18/2006 - 07:01
Really? Steven, I don't have the website anymore, but there was one posted a while back....Producer something...I'm sure that there will be readers who will chime in with the address. Anyway, a $5.00 (!!!!!) mic pre WON over much more expensive makes/models!
That's not to say that quality components don't yield quality results, but...price doesn't GUARANTEE that, either. Case in point:
I had an Avalon 737 box. Paid $2K fer it. My $600 Grace 101 is cleaner, more transparent, and quieter. That 737 has long since flown the coop!
BTW, I have spent several years in R and D at a medical imaging manufacturing facility. A typical cost-to-sell price ratio for an electronics device, no matter what market niche it is geared towards, is roughly 6:1,as far as componentry is concerned. Bottomline:a layout that costs the manufacturer $100.00 to produce is going to add $600.00 to the selling price...YIPES! This is why boxes with fancy packaging and high quality components cost so damned much!

Pro Audio Guest Sat, 03/18/2006 - 07:48
StevenColbert wrote: [quote=scarface]would it actually make what your mic sound better?
One word...
YES
All preamp's are small circuits, that add gain to the signal. And all companies make different designs to achive gain. So ALL preamp's sound different in one way or another.
If a preamp is made of $150 worth of electronic components then the sound will be cheap sounding and most likely not that warm.
However if you have a preamp that cost about $1500 (not including labor cost) It will be 10 times better IMHO.
And SHOULD sound way better than any of the cheaper designs that use lesser components and shortcuts to achive gain.

cheap parts= cheapest sound
good parts= good sound
best parts= best sound possible
Don't mean to diss you here, Colbert...but this is basically incorrect on just about every level.

Its very true that the various different pres offered by different manufacturers offer their own "colors"...

And its also true that certain microphone types (in particular, most ribbons) can sound quite strikingly different with different pres, because of the way they load (or don't load) the input of the pre.

But the key word of the day here, is that they sound DIFFERENT. Different may be better, may be worse. One mic/pre combination used today on THIS material may sound "best", but tomorrow that same mic/pre combination may sound "worst", on some other material.

So, the reason that studios keep a number of different mics and a number of different pres around, is because each combination has its particular "strong suit", that applies particularly well to certain situations. Having a variety to choose from gives the engineer some tonal options BEFORE he starts twiddling the EQ knobs.

Another reason to have a variety of mics/pres, is BECAUSE each one has its particular "signature sound". If you use that particular combination for every track in a mix, while they individually sound pretty good, you can start to get a "buildup" of that characteristic, which can often result in some undesirable, hard-to-fix situations. So its common, in a studio where you have access to several choices, to "mix things up" a bit, in your mic/pre selection.

But to address the "more expensive is better"...

When you buy a mic pre, what's inside?

A couple of opamps, or perhaps a tube, or perhaps an IC chip.

Some resistors, some capacitors

A circuit board

A power supply (may be a wall-wart)

Maybe an input transformer, maybe an output transformer.

Some potentiometers. might be a meter and some LEDs.

A case. Some connectors

If you go out to the electronic suppy houses, you find that you can buy all that stuff for perhaps a couple hundred bucks, even if you get the BEST burr-brown discrete opamps, the BEST Sowter/Lundhal/Jensen transformers, the HIGHEST quality caps an closest tolerance resistors...and if you buy it in bulk, the way a manufacturer does, you can build a world-class mic pre for about 150 bucks US in parts.

What's the expensive part? Its today's next word of the day...DESIGN.

I could select the best parts available anywhere in the world, and design a mic pre all by myself, and it would, I'm sure, sound entirely pedestrian, probably no better than the mic pres in my console.

Some of the pres out there in the mass pro-sumer market would be improved by substituting in better components, some wouldn't be helped.


In conclusion, the statement I'd make about cheaper pres/expensive pres/console pres, is that the cheaper the mic pre, the less often you'd find that its the OPTIMAL CHOICE for a particular situation. It may EXCEL at some one thing, but be next-to-useless for other things. In other words, the higher the quality (and thus, probably more expensive), generally speaking the more versatile.

Although, there are cheap pres out there that are great...the FMR stuff comes to mind. There are very expensive pres out there that are great, but not very versatile at all...some focusrite stuff comes to mind.

Console pres are generally designed NOT to excel, or to have strong character, but to be as generally versatile (NEUTRAL) as possible. In other words, the pres in your board will almost never be a perfect choice, but will almost never be a BAD choice. (with the caveat that we're not talking about a really cheap board like a behringer or alesis or the like).

Anecdotally, the other day, I was sticking an SM57 into the face of an 8" speaker, and after listening to what I was getting, I finally unplugged the mic from the $800 pre, and went directly into my console's channels strip mic input. Sounded much better. Today, that is.

Likewise, I plugged my Chapman Stick into a $150 presonus blue tube, and generally liked it a lot better than direct into the board or the $800 pre...but plugging my old fender bass direct into the board (with a DI) sounded better.

A more expensive pre will typically be your standard "go-to starting point"...but don't be too surprised if you end up liking the sound of a cheaper solution better in a given situation.

dwoz

Pro Audio Guest Sat, 03/18/2006 - 08:07
StevenColbert wrote:
If a preamp is made of $150 worth of electronic components then the sound will be cheap sounding and most likely not that warm.
However if you have a preamp that cost about $1500 (not including labor cost) It will be 10 times better IMHO.


Actually, its FAR MORE LIKELY to sound 1% better. Like golf, equipment design/quality is not much of a factor for the 500 yards between the tee and the green, its all about what happens at the final 8 inches.


dwoz

0db Sat, 03/18/2006 - 08:26
5$! mmm....That hardly buys a pair of transistors, hehehe...

Anyway, i have to pray my Brian Eno´s credo:

"i´ve been in state-of-the-art studios that sounds like s**t, and i have been in dark, weird studios that have the most uncommon and undesirable blend of gear that sounds like heaven"

Having said this, what is important at last is how you hear it. Outboard pre´s usually gives you more parameters to adjust, and a better sound quality because they are specialized gear that has been designed with that in mind. The signal path, amp topology or class, the transistors, Mosfets or tubes, digital out options, and the overall quality of components, should give you better and different tastes for every use. Most of the expensive gear uses hand wound transformers with silver coils, for example, that also should help achieve better sound. There are also rack units that comes with 8 pre´s and firewire option, very convenient, easy and efficient way to record a drum and track it directly to your recording software.

Everything counts. Mics, pre´s, the booth, even cables!. Many of us cannot afford a 2K$ Manley or an Avalon pre, so there´s is when you have to come and squeeze out the potential of the gear you have. Maybe a Joemeek pre, can do the job, and you will pay like 500$ or so for it, or maybe you will end with a 5$ pre that sound like heaven. There are lots of brands and models. And lots of opinions and advices on how to choose one in this forum. this is one experience that i had and wrote some time ago: (Dead Link Removed)

My final advice is: if your board is good enough and your budget its not, use them. Try to improve everything else, good cabling, good mics. If you have enough money, and not satisfied with the sound you get, then try a external pre. The one YOU like.

Good Luck
Juan

0db Sat, 03/18/2006 - 08:28
5$! mmm....That hardly buys a pair of transistors, hehehe...

Anyway, i have to pray my Brian Eno´s credo:

"i´ve been in state-of-the-art studios that sounds like s**t, and i have been in dark, weird studios that have the most uncommon and undesirable blend of gear that sounds like heaven"

Having said this, what is important at last is how you hear it. Outboard pre´s usually gives you more parameters to adjust, and a better sound quality because they are specialized gear that has been designed with that in mind. The signal path, amp topology or class, the transistors, Mosfets or tubes, digital out options, and the overall quality of components, should give you better and different tastes for every use. Most of the expensive gear uses hand wound transformers with silver coils, for example, that also should help achieve better sound. There are also rack units that comes with 8 pre´s and firewire option, very convenient, easy and efficient way to record a drum and track it directly to your recording software.

Everything counts. Mics, pre´s, the booth, even cables!. Many of us cannot afford a 2K$ Manley or an Avalon pre, so there´s is when you have to come and squeeze out the potential of the gear you have. Maybe a Joemeek pre, can do the job, and you will pay like 500$ or so for it, or maybe you will end with a 5$ pre that sound like heaven. There are lots of brands and models. And lots of opinions and advices on how to choose one in this forum. this is one experience that i had and wrote some time ago: (Dead Link Removed)

My final advice is: if your board is good enough and your budget its not, use them. Try to improve everything else, good cabling, good mics. If you have enough money, and not satisfied with the sound you get, then try a external pre. The one YOU like.

Good Luck
Juan

ouzo77 Sat, 03/18/2006 - 09:19
i have a question, too!

i'm thinking about buying a preamp, but my budget is very low, close to non, so i googled a bit and found two pre's:

STUDIO PROJECTS VTB1 for 118€ (i think about 100$ US) and ART TUBE MP STUDIO V3 for 88€-

can anybody say anything about those two, or recommend another one in that prize range?
they would be in my budget and since i don't really have a studio, just a computer with an 8-track 16bit audio interface i wouldn't buy an expensive one, anyway.
til now i plugged my guitar and bass directly into the audio interface. but especially when routing the guitar through guitar rig the noise floor of the audio input gets amplified as well. i hope to reduce this by going through a preamp, which will result in a higher input into the audio interface, thus hopefully reducing the amplified noise.
does this make sense?

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