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Basic question!

somebodyelse

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#2
Traditionally the preamp looked after switching between multiple sources (tape, radio, CD, LP etc.), adjusting volume and maybe balance and tone controls of some sort. Depending on the power amp it was designed to match it may or may not provide gain. All but 'passive' preamps would buffer the signal. The power amp would have a single input and no volume control.

The one you linked has 2 sources, the analog RCA connectors on the back, and bluetooth. Switching is automatic - if there's a signal on bluetooth then it uses that, otherwise it uses the analog input. It has a volume control and basic tone controls, plus a couple of valves because they appeal to some people. Based on the measurements of other cheap valve stuff here it'll probably have a load of distortion. If you've got one fixed level analog source (output of a USB dac with no volume control of its own, say) and want to be able to play bluetooth from your phone too, you like distortion, and you've got a power amp to connect to, then this could be the product for you.
 

LTig

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#3
Hi I have a very simple question!
I am getting/building a Sound system and I came across this:

http://www.doukaudio.com/nobsound-h...tereo-bluetooth-preamp-treble-bass-p0130.html

And want to now what it is and for what it is used?!
I now that usually a preamp is used to amplify the sound signal for the amplifier! But amplify what signal, and when?

Hope someone can answer my question!

Xxx
You can connect one line level source like a CD player and also stream music from a smartphone via blutooth. Both are then controlled by the volume before being routed to either a power amplifier or active speakers.
However, in this very low price range you should not buy tube equipment, chances are high for a lot of distortion and noise.
 
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#6
Ok and what is a Analog RCA input? What sort of audio source can you connect to this preamp?!
MP3/Pc/CD Players???
 

Willem

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#8
MP3 bluetooth is sonically inferior. What device is it from? Does your cd player have an optical or coaxial digital output?
 

somebodyelse

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#9
Ok and what is a Analog RCA input? What sort of audio source can you connect to this preamp?!
MP3/Pc/CD Players???
RCA refers to the connector - it's pretty much standard for consumer audio connections between separates, with a pair of connectors colour coded red for right and white for left analog signals. Most hifi separates sources and many AV sources will have compatible outputs using the same connectors, so tape decks, CD players, DACs, DVD players, TVs will most likely work. You can also get an adapter cable like this to connect the RCA inputs to the headphone output of things like phones, laptops, tablets etc.

The RCA connector is unfortunately used for other signals too, usually with a different colour coding. SPDIF digital audio usually uses a yellow RCA connector, usually found on CD players and DACs. AV equipment (TVs, DVD and BluRay etc.) used to use RCA connectors for analog video signals, but this is less common now. They used yellow for composite video and red, green and blue for component video.
 

Willem

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#12
This Nobsound kit is undoubtedly crap and a waste of money. Anything decent will cost more, I am afraid, and this is not audio snobbery. So what do you want and how much budget would you have?
The Audio Player player is interesting: does it have a line output or only headphone and usb digital? As for the rca output of the cd player, look in the manual to see if it is digital coaxial spdif or analogue rca.
 
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#13
The Music Player has Bluetooth headphone and usb output!
As to the CD Player, I am currently not at Home! Sorry.

And to Nobsound, do you think the Make is krap or is it god for none Tube Products?
 

Willem

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#15
For what? Just a preamp, or an entire system with a power amp and speakers as well?
 
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#16
Well I already have two Amps, and speakers. But I still have a sub witch I would like to use, but for that I need a third amp! I was thinking of a Mono Amp! With a round 150W Rms to 4 ohms! But in Total I don’t have more than 200/250$!
But I like the idea of having a separate unit (Preamp) where i can control my System!? I Hape that makes sense?!
 
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#17
My thought is of having a stereo system, but in stead of two main speakers and a sub, I was planning 4 main speakers and a sub?!

I already have all the Speakers !
 

Willem

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#18
It does not necessarily make sense if budget is limited. What amplifier do you have? Why four speakers in a stereo system? What speakers do you have? Why do you need an amplifier for the sub? How big is the room?
 
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#19
To the Budget I am 14 years old, so I do not have a proper job yet!

My first amp is a Nad and my second amp is a Sony! Sorry I do not have the Models of the amps, because I am still on Holiday! But the Nad is a stereo channel (two channels!) with 25W Rms to one Channel and 70W Max to one Channel (this is to 8 Ohms!) the Sony is a 4 channel , with 60W Rms to one Channel and 80W Max (also 8 Ohms!)
 

Willem

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#20
Lucky you to be on holiday still. These two amplifiers are both probably more or less ok. However, they are unlikely to have digital inputs. So the question becomes what to do with the sources. The CD player probably has an analogue output and the quality is likely to be rather good. So you could connect that to one of the amplifiers without any worry. There may be a litle mismatch between the strong signal from the cd player and a sensitive aux input, which will show if you already have a loud sound without turning up the volume very far. If that happens, buy some cheap in line attenuators.
The pc will have both a digital (probably) usb output and an analogue one. The latter may be of good quality, or not, that is hard to say. Many recent computers have better audio than before, and desktops are often also better than laptops (but Macbooks can be pretty good too). I have been pretty successful with a cheap Behringer UCA 202 usb DAC (digital to analogue converter). You may not need this. Do you use the laptop to stream Spotify from the computer and as a source for your portable player? If, in the end, you only need a source to stream Spotify and perhaps TuneIn for digital radio, all you need is a Chromecast Audio. This has been discontinued but can still be had here and there. The analogue output would be good enough for your purpose.
Does this help? Tell us more about your sources: Spotify and cd?
 
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