Some basic questions...

[will852]

Hi Folks,

I'm brand new to this DIY audio malarky so I hope you don't mind me asking some questions which probably, and hopefully, have some really obvious answers. Oh and you'll have to excuse my rather basic understanding of the terminology!

Firstly I'll explain what I'm trying to do.

I'm going to attempt to build an Ipod dock which uses tube amp technology and will hopefully include a parametric EQ and -10 to +4 dBu line level output.

I'm doing it for my dissertation for a music and sound technology degree.
Why you may ask?
Well, the point of it is, is to see whether it is possible for someone with basic knowledge to build such a thing in a home workshop.




Ok, so here are my silly questions:

1. I plan build the thing by making a pre amp with the line level and EQ capabilities, which then goes into a power amp.

After looking on the internet it seems my budget dictates I could only use tubes in the preamp, not the power amp.
Is that like trying to put chalk and cheese together?
If that is the case then should I scrap the tubes altogether?



2. Is there a standard input for a preamp? 1/4" jack or RCA etc? or is it just down to what you build.
Say I bought a kit off the internet for a preamp, what would i expect to see where the input is?
I ask as I'm assuming I will have to build a cable which goes from the 30 pin iPod connector to the preamp.



Sorry if these are very silly questions, but I'm brand new to this!

All the best,
Will

[will852]

I should add that the line level adjustment would be so I can include an output to an external power amp to bypass the built in one, which I'm assuming at the moment will have a 0dBu input.

[Eli Duttman]

Standard for both I/P and O/P connectors is RCA for single ended and XLR for balanced. You will find some equipment with DIN connectors. XLR is pretty much the rule in "pro" sound equipment.

The parametric EQ is going be a challenge. Do a Google search for Philbrick operational amplifier. Mr. Philibrick was there long before ICs became available. You're going to have to replicate a few of those "puppies".

[chrish]

Plenty of people mix tube and solid state. Many have tube pre amps running solid state power amps. Any cd player feeding a tube amp is a mix of both technologies. I am assuming that the parametric EQ is part of the project? I don't have an iPod, but assume that EQ is a function available on that device, like on iTunes?

Anyway, a tube pre-amp is possible, but you will have to consider that it will probably be larger and more expensive than solid state. You will also have to consider the heat of the tubes, you will not want them right next to your iPod. As for the power amp, you could probably do a simple chip amp (there is a forum for these) that would meet your needs.