A few questions for a DIY newbie.

[Grumple]

Firstly I'd again like to say thankyou to everyone involved with ASR for making HiFi fun again.

TLDR: If I split the output from a preamp (for example with a Y-Splitter cable) do I need to worry about impedence and/or voltage level?

Some may have noticed my desire to have tone controls. I feel like I spent a week or two spamming the site with messages about it, during that time a number of people pointed out that I could very easily build my own pre-amp module with tone controls. At the time I was hesitant because I didn't feel I had the knowledge. (Some background info...I was a delinquent teenager who had trouble at home and often caused it at school, consequently my knowledge is incredibly patchy and my confidence, with electronics, similarly patchy!)

So casting aside the adult delinquent who haunts my every-day whispering sour "why bothers" into my ears I decided to jolly well do it and try and learn what I should have learnt back at school. As a result I've been reading a primer on electronics. This is going great and some stuff is flowing back into my accessible memory. However the gaps in my knowledge are becoming ever more obvious.

I want to have multiple outputs from the preamp that may, on occasion, be used at the same time. I also want a sub woofer out. The TLDR question above relates to these situations. My ultimate aim is to also build monoblocks would these also be affected?

I'm sure I will subsequently have more noob questions so any help or advice that can be offered is and will be greatly appreciated.

 

[somebodyelse]

It depends on the source and the devices you're connecting to, but in most cases a Y splitter would be ok. The rule of thumb is to have input impedance >10x output impedance so that variations in impedance with frequency won't alter the frequency response significantly. Typically sources will have something like a 100R series resistance between the output opamp and connector, while amps etc. usually have an input impedance in the range 10k to 100k, so well beyond the 10x ratio. With the Y cable the output sees the parallel combination of the input impedances of the amps, which will be lower than either of the amps alone. Typically this isn't a problem - 2 amps with 10k input impedance still gives 5k in parallel so there's still a good margin. It can be a problem if you have unusually high output impedance, unusually low input impedance or both though. It's unusual, but there can be real world combinations where it's a problem.

 

[paddycrow]

The only situation I've used Y splitters is to bi-amp a set of speakers.

If you want multiple outputs, I would look for a preamp with main and aux outputs. If you want to integrate a subwoofer, it's handy to have a subwoofer output and bass management capability.