Friends hi-fi system not very good, what do you do or say?

Generally, sound is subjective. If you know that, the answer to your question is pretty simple. 

If it sounds great to him then that’s all that matters no? If he specifically asks for your assessment then it’s fair game. If your tight with him then tell him it sounds like shyte….I go at it all the time with my HiFi buddy who has unlimited funds and just can’t get it right. 😂🤷‍♂️

The OP can answer this question him (or her) self.

Reverse the situation.

You invite a buddy to listen to your great, great system, one that you've spent years tweaking.  Your friend has her own spectacular system, which cost her about the same, but she quickly realizes that it sounds a heckuva lot better than yours.

What would be appropriate for her to say, if anything?

@emergingsoul wrote:

So you’re going over to someones home and they give you a tour and they have a hi-fi system in a room. And while visiting of course they turn it on for you not knowing that you have a very nice system in your home and you notice immediately it’s just not very good. But then you’re used to the very in you’re listening experiences. So what do you do when they ask you what you think?

Do you say sounds really good?

Do you make suggestions?

Do you feel a desperate need to tell them about your system?

Kinda feels like a forced premise here, and in the subject title you refer to the individual as a "friend" whereas later it appears you’re not really acquainted with him.

In any case, from my chair, going to someone else’s place and listening to their setup comes with the necessity of knowing about who they are in addition to their aspirations, and then adjusting your feedback accordingly. Maybe the one you’re visiting is perfectly happy with the sound as is (even though you may disagree) without being overly ambitious with the outcome, and that being the case he’s likely not in a place to receive critique, nor should he to my mind. On the other hand he may be dissatisfied with the sound himself (maybe because of practical circumstances, not enough time/energy, family considerations, etc.), and then revealing your own interest in the field you may sense an invitation to help him out in his audio endeavor, in which case I’d likely oblige. If I knew the fella very well and had heard his setup at numerous occasions and then felt something was amiss with the sound coming from his system, I’d definitely let him know honestly while also being surprised perhaps if he felt differently about it. If some audiophile I don’t know wants me to be ruthlessly honest about the sound from his setup, I’ll be just that.

Still, it’s important to me to respect whatever audio endeavor this or that individual is pursuing, and then meet them on their own field, so to speak. My interest initially would be knowing about his preferences and ideas, and then over time may share my own if it feels prudent. Listening to other audio setups can be inspirational, and after a bit of getting used to a different sound compared to the one you’re treated to at home, great music experiences can emerge here and there as well.

Tidbit: my approach may be different than many around here, but that’s not to say I can’t appreciate the sonic paths of others. I don’t necessarily like the sound of horns if their "horny" imprinting is all over the place or coherency is left by the wayside, but I like what they can channel and communicate if properly designed, sized and implemented. Whatever works..

Life long lesson: Only give advise and/or make suggestions if you are asked to contribute. 

@lak 

On the money.