For a 300Ω headphone, the SIVGA is quite efficient and I never had an issue powering them with any particular genre of gear including some average power capable dongle DACs.
It seems power doesn’t faze these much and there’s not much gain by using high power amplification if the available power is enough. So, if you already have a pair and are wondering if upgrading to an ultra-powerful diesel power amp although your current setup works fine don’t waste your time.
I used so many different types of amplifiers with the SV023 and concluded that above 100mW and below 2000mW almost all sounded the same far as volume quantity so I would consider them very efficient regardless of their high impedance rating.
To mention a few of the setups I used with the SIVGA SV023. First off was the iFi Audio iDSD Diablo which I find to be incredibly flat but sometimes hot so I contrasted that with a Schitt Audio Asgard using an AK4490 DAC module which tends to be flat but warm and not as hot sounding.
I preferred the warmth of the Asgard with the SV023 although feeding the Diablo with a warmer DAC solved the issue. I was actually the daring one who used Diablo’s 4.4mm output port as an input and found the hidden feature engineering forgot to mention.
So, I fed the 4.4mm out of a Gryphon to the 4.4mm supposed inputs of the Diablo, and to my surprise, it became a very formidable combo with the SV023 because of the added color the XBass and XSpace introduced to the pairing.
It seems the SIVGA SV023 likes warmth and color over bright-sounding amplification and perhaps sounds best on tubes or tube-like warm-sounding gear.
My apologies for not testing them on a tube amp but I’m a solid-state guy. The SV023 likes some color and becomes more musical when color is added but on the flip side, it becomes analytical with neutral-sounding gear which makes these quite versatile.
For portable use, I also used various dongles, the MoonRiver 2, and the ddHiFi TC44C to mention a couple. I also used the iFi Audio xDSD Gryphon stand-alone on balanced and they all seemed to get along with the SV023 and did not mind the 300Ω rating at all.
HIFIMAN has become a formidable headphone manufacturer. To prove that point one only has to ask around what the best cans are under $350 and many will say the Sundara.
Ask again but raise that price to $500 and most will say the Edition XS. I could go up or down some with a similar result but you get my point at this point.
When first introduced retail price was set at $499 but that price has gone down considerably and nowadays you could buy Sundara at an authorized dealer for about $300 which makes them quite a bargain. They do contrast the SIVGA SV023 by using a planar driver instead of a dynamic.
My assessment and since this particular fact is rarely discussed I’m going to throw it out there. The size of the Nano diaphragm or NSD frame seems to be around 94 to 96mm mounted on 105mm cups according to my measurements and the diaphragm itself is around 80mm.
The cups, pads, and head strap are comfortable but I wished they were all replaceable. You can pad swap but the headband is permanently incorporated.
I know people who own Sundara claim to feel some variations in clamping force. Or perhaps frequently worn units stretch out a bit as mine is since I find myself constantly using them.
One area that most complain about is the stock wire and the rubber tubing feel of the stock cable that comes in the box. Most people just go out and buy a balanced cable since the Sundara benefits from high power, unlike the SV023 which seems to be fine on various powered amplification levels.
For certain the smoother and more polite presentation belongs to the Sundara. The treble is more relaxed and so is the midrange. It’s also the more out-of-your-head experience with a wider panorama and deeper outward projection in front of the listener compared to the more intimate inward presentation of the SV023.
Perhaps the larger panorama is due to the larger 80+mm surface of the planar driver versus the 50mm dynamic-sized driver. But it’s probably due to the more open back design of the Sundara and the large open back grille and the more breathable design.
Bass performance below 40Hz is more pronounced on the Sundara, especially the 2020 revision, which just involved a pad swap over to the Pali pads from the Focus pads.
Midrange response was tamed by these pads and the bass gained perhaps a couple of decibels on the lowest frequencies especially when they wear down some.
I hate to say this but the SIVGA SV023 excels in one area in particular over the Sundara and that is in detail retrieval. You might like the forward and introvert presentation that gives the music a lift in brightness and overall presence as well.
HIFIMAN Edition XS
Dollar per dollar the Edition XS is another HIFIMAN can that always makes the best for under $500 bucks list and deservedly so since it can perform very well in many areas especially in bass response and in particular since the introduction of the stealth magnet design.
The asymmetrical cup design was reserved for the top-tier models and the Edition XS is the lowest price HIFIMAN to employ that design up to date.
3.5mm plugs are used at the cup level for connectivity which is similar to the Sundara connectivity and many other non-HIFIMAN branded cans so it is the more versatile and the easiest to find a cable.
Going back to the asymmetrical design it has a very large diaphragm and the sound seems to surround the listener. I feel the driver size reflects in its performance by creating an illusion of sound that is quite large which helps the staging a bunch.
HIFIMAN had a rocky start when it comes to headband design but this new design seems to be holding up well. However, it seems a bit humdrum to use the same headband on budget models and top-tier models.
The headband is functional but I still prefer the original HIFIMAN headband assembly and wished they kept it and perfected it.
Everything else is fine. The cups are made of metal and black anodized. The stock cable is adequate and to be honest, I like it over the one that came with the Arya and the Sundara which has that rubber tubing construction.
Most of HIFIMANs stock cables measure 3 feet which I do prefer for portable use but the 6-foot stock SV023 cable is best for desktop use.
Both these cans sonically are contrasting, to say the least. If we start with the bass response the clear winner is the XS. I actually consider the XS HIFIMAN’s most bass-heavy headphones or in the top 3. The Edition XS can almost reach bass head levels of bass output with a good amount of punch as well.
The XS seems more omnipresent that can project a decent amount of depth along with a wide picture that presents along with height a nice spacious panorama of music that is fun to listen to. The XS is a fun-sounding headphone and not so much a studio reference can.
The XS is more aggressively tuned which contrasts with the signature of the SV023, which aims for balance, tonal accuracy, and a high level of nuance retrieval.
I still would say the Edition XS has more of a fun factor in its sound signature and the larger stage does it for me. Plus the killer bass response is lacking on the SIVGA SV023.
However, the SV023 is indeed the more delicate listen that seems to remove a veiled layer that enhances their overall level of clarity.
It seems clear that the SIVGA SV023 is aimed at those who are looking for a studio monitor detail retriever with a touch of fun with hand-crafted cups and an overall artisan appeal. There are other factors that count here for example comfort.
It offers a luxurious listen around the midsection with rather high levels of detail production. Their only lack is in the low bass tuning which can be easily remedied by boosting with equalization or a DSP implemented bass boost. Just do not expect a bass headphone because these cans aim for balance more than anything.
This is a cutthroat price category and the competition is fierce. The fact that there was a price drop on the SIVGA SV023 means that SIVGA understands it’s in a tough fight but considering all the good points of the SV023 I would not scratch them off my list yet. Quite the contrary, in fact.