can the analog in accept High Z load

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moxi
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can the analog in accept High Z load

Post by moxi »

Hi,

just want to know if I can plug directly an HighZ input (guitar/bass) into the analog input of my pulsar2 or luna2?

Does this is possible with the creamware rack (a16)?
Immanuel
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Re: can the analog in accept High Z load

Post by Immanuel »

The answer is in the manual (input impedance). An the answer is no. This means, that you can do it, but it will not be an optimal solution.
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garyb
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Post by garyb »

the input is hiz, but it's line level. a guitar is mic level. you'll need a mic pre with a hiz input or the level will be low and the signal noisy...
Immanuel
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Post by Immanuel »

Luna has 10 kOhm input impedance, and A16 has 20 kOhm input impedance. When talking High-Z we are usually starting at somewhere around 250 kOhm and up. For a guitar or a bas, 10 kOhm is definitely not High-Z.
moxi
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Post by moxi »

thank for the replies ! (I don't own the manual, I only own second hand cards..)

so, as my Filtrex2 will go away from my studio, I will be obliged to buy some more DI box :cry: ....

If CW can ear my crying, and want to produce a special plate ...it's now necessary as they produce so attractive guitar and bass amp simulation!!!
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garyb
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Post by garyb »

a mic preamp with a hiz input is what you want.
Immanuel
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Post by Immanuel »

Download the manual. You will likely need it again at some other time.
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astroman
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Post by astroman »

I can only comment on the passive side of guitar/bass pickups
in that case it's not just the impedance in kilo/meg Ohm, but also the design of the guitar (passive) electronics and the input stage that matters.
there is a lot of interaction going on between those parts regarding frequency response, it can be quite surprising - negative and positively... :D

your 'clean' sound is affected most, or it's the most obvious to notice - if it's an important choice (e.g. you plan to invest a serious amount into a preamp or you own a great instrument), I'd bring the instrument to a shop and try it live on the gear.

I've recently tried a small bass combo in a shop, quality brand, 1k Euro range with a 1k Euro instrument I picked from the shelf - great sound, and it had all the properties like direct out, adjustable tweeter, compresor etc...
This would have been MY amp of choice - but never say never, so next time I brought my own bass along.

Whatever I tried or dialed in - it s*cked completely - a muddy, fluffy undefined no-tone :o
It then turned out that an ashdown top with a 2nd hand H+K 4x10 was the thing that made my bass really going ... (just do prove it wasn't the guitar) ;)

not that I want to confuse you, both Immanuel and GaryB are right.
A quality(!) mic pre with hi-z will have that input impedance Immanuel mentions.
A non-quality thing (regardless if DI or pre) will be dissapointing as soon as you have the opportunity to compare it to a better one - which does NOT necessarily have to be (much) more expensive.

If your instrument has active electronics, then this 'buffers' the afforementioned frequency dependant effects and choice is less critical.

cheers, Tom
moxi
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Post by moxi »

ok...

let's go on with technical specification (now I've read the manual ;) ).

this info are missing : for the Pulsar2 (scope project) with the classic IO, which is the output and input levels? +4dB or -10dB as the Luna?
I know it's unbal. but I've gear that have unbal. in/out at +4dB, so I doubt...
voidar
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Post by voidar »

It doesn't really matter. line inputs are not DI inputs.
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garyb
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Post by garyb »

unbalanced line level is always -10 or -20db, never +4............
moxi
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Post by moxi »

I was thinking the same until I see that my Lexicon mpx200 accept unbalenced signal from -30dB to +4dB...but it's the max...

and I discover today that this one accept HighZ input (up to 500k Ohms) :)
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garyb
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Post by garyb »

yes, the range and reference point are not the same thing. +4 balanced speaks to the reference, -30 to +4 speaks of a range.
hubird

Post by hubird »

wow...
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darkrezin
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Post by darkrezin »

You shouldn't have a pre/DI inside the computer, it would pick up a lot of noise... there's not a lot of point building it into a soundcard (well except some crappy consumer stuff or a card with a breakout box). You need an external pre/DI.
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