If you own a pair of KZs, or CRAs, just go for it. It improves everything. More resolution, better soundstage, more vocal body, more clarity in treble, improved, tight and fast bass decay, and overall better sound representation. And if your device has low volume problem, as most of the phones have these days, these increases the volume output by two fold. I just cant express in words what difference these make. They just make hella difference. They just give that extra resolution and emphasise every single hidden beat. Vocals are improved and extra bright iem will benefit because they bring the sibilance a bit down. So if anyone is thinking of getting a DAC/AMP. just try these first. Most bang for the bucks.

I wanted to give a great review because i had such a positive vibe about it before..when it arrived and started using it, ..i could not find much improvement with my KZ zstx other than increase in volume. Hence unable to rate. Maybe a headphone guru can help on what iam missing and what to expect?

The build quality, audio quality is fantastic
However, sometimes it automatically takes over control of volume and raises it to full or lowers it to zero on my Oneplus Nord or my laptop

If you have a high impedance headphone then you'll hear a increase in the volume. Sound quality is as same as my phone's inbuilt headphone jack.
But I think for a phone without 3.5mm jack this dongle is necessary.
If you're trying to improve the sound quality you have to spend more.
I used Samsung Galaxy M32, A31 with KZ EDX, KZ EDX pro, Beyerdynamic Beat Byrd, Soundmagic E11c

I ordered this dac as my OnePlus dac stopped working. I didn't want to spend much so I went with this. I am using KZ ZS 10 pro with this dac and they are sounding much better than the OnePlus dac. I am using this with apple music lossless and Hi Res Loseless songs and they are sounding great on this

I paired it with the Hifiman re-400 which has a bright-neutral tonality (15 months old) and Final e3000 (200+ hrs old) which sports a properly warm tonality.
Source: Spotify (non-premium)
Devices used: Samsung M30s and Asus g14 gaming 2021
Burn-in: The Avani was aged for 20hrs or so

**Straight out of the box the bass on my e3000 felt out-of-whack, vocals edgy and shoved in your face. That was all gone after I left it playing for about 20 hours at 70% volume without listening to it in the interim**

TL;DR
The Avani is Great value as an amp, "If"you really need one for an underpowered IEM or headphone. I did not hear any DAC resulting benefits upon hours of critical listening (quiet room, proper ear seal, several genres...)
So why not 1 star? Because the damn thing is built so well and at least works as an amp... And for ₹899 it'd be plain cruel!

Pros
1. Extremely well built
2. Solid connection/fit. There's a nice click when the headphone connects
3. Amplification jumps up by a lot. Off my phone as a standalone source the E3000 needed to be at 90-100% volume on many tracks whereas with the Avani I can't go beyond 70%.

Cons
1. The biggest con - I have a feeling this is an 'amp only' because a) If I A/B against my phone (volume matched) I can't tell a difference b) My Asus g14 gaming laptop has a very warm sound (while the M30s smartphone is relatively cold/neutral) as soon as I connect the Avani to the laptop it sounds significantly warmer than it does on the phone. To me this suggests that it takes the sound signature of the host and pumps up the volume (like an amp should)... But there are no 'quality' benefits to be had over my laptop/phone. I tried discerning nuances across several tracks and genres for hours, I can easily pickup nuances on prolonged sessions across the IEMs and headphones I've owned. Just saying there's nothing wrong with what I heard (or did not).

The box says "Special Thanks to #donglemadness"... And it seems Andy is the only Special one going crazy over this, up-rating it over DACs costing 5-7x more... Are you thinking what I'm thinking?! Or is it a 'Special IEMs required...' 'exotic audiophile ears needed' thing? There's of course nothing wrong with showing gratitude, to 'one paticular reviewer' and making it obvious while at it, he's Wild Lee afterall.
You be the judge.

My conclusion is this... It's either an 'amp only' or for whatever reason it doesn't seem to bypass my phone's or Laptop's DAC. If it did it should've retained its own sonic characteristics irrespective of the host... Or perhaps I've got a lemon where somehow the amp works while the DAC doesn't, if that's even possible off a single chip solution (i.e. without a dedicated amp module)

It didn't seem right to ask HZ for a replacement because it is working (If only as an amp) and I don't want to judge the brand off this experience either. Infact I've used the VE monks and I've also ordered the Abigail, fingers crossed!

I have been testing venture avani with venture monk plus, oneodio pro 10 , works good, i could feels some difference, good enough for beginners, i suppose.