• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

IOTAVX SA3 Stereo Amplifier Review

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
25,948
Likes
57,769
Location
Seattle Area
#1
This is a review and detailed measurements of the IOTAVX SA3 integrated stereo amplifier with built-in DAC and subwoofer output. It was kindly purchased by a member and drop shipped to me. It costs £399.00 (on sale from £449.00) on company's website. Hard to find it on sale in US but found one ebay listing for $498.

SA3 nails the industry design with svelte chassis, dot matrix display and judicious use of backlighting for the logo:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Audio Review.jpg

I left the plastic on the display as otherwise it looks nicer than it does in the picture. A reassuring power button is the left and a nice feeling rotary control handles the volume. If you press it, it becomes an input selector. Very nicely done.

Back panel shows a lot of inputs:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Back Panel Inputs and Outputs DAC Toslink Au...jpg

There is phono input which I did not test. I did test both analog input and Toslink digital input. Sadly there is no USB input. There is bluetooth but no streaming support over network.

Let's get started by using the line in (analog) input to the power amp and work our way out to the DAC section.

Amplifier Audio Measurements
With integrated amplifiers with volume controls, I adjust that to produce roughly 29 dB of gain which is a THX "standard." That gives us this dashboard:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Audio Measurements.png


Distortion dominates with second harmonic telling the full story. Wish channel 2 was as good as channel 1 but this is typical. Averaging the two we get this kind of ranking:

Best integrated stereo amplifier review 2020.png


So above average among 89 amplifiers tested so far (!). But not state of the art by any stretch.

Noise performance is good:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In SNR Audio Measurements.png


You almost clear the CD's 16-bit dynamic range at 96 dB at 5 watts output.

Typical of class AB designs, bandwidth is abundant:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Frequency Response Audio Measurements.png


Should the zombie apocalypse come, you can hook up a few hundred yards of wire to the speaker wire and have yourself an AM transmitter power amp!!! A microphone and simple modulator and you could be talking to people thousands of miles away at night....

Crosstalk is surprisingly good:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Crosstalk Audio Measurements.png


If you look inside the chassis, you realize why. A toroidal transformer is in the middle with each amplifier nicely separated from each other by good 8 to 10 inches.

Power output at 4 ohms falls a bit short of the spec:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Power into 4 ohm Audio Measurements.png


And I am not too happy about the constant rise in distortion from just 1 watt, ending worse than one of our worse performing Audio Video Receiver (the NAD T758).

It is a bit happier driving an 8 ohm load:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In Power into 8 ohm Audio Measurements.png


That's not a lot of power though so best get an efficient speaker is 8 ohm is the language it speaks.

Fortunately burst power is quite decent (only 4 ohm shown):

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In 4 Ohm Power Peak and Max Audio Measu...png


Changing the frequency of the test tone hardly bothers the SA3:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Line In 4 Ohm Power vs Frequency Audio Measu...png


Other topologies such as Class D make a mess out of this measurement.

DAC Audio Measurements
Taking advantage of the pre-amp output, I fired off a few DAC tests to get an idea of how good that subsystem is starting with our digital dashboard:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Toslink Digital Audio Measurements.png


OK, this is a bit disappointing. You want a SINAD here that is 10 dB better than the amp for it to be transparent. Here it is actually a couple of dB worse then the amplifier which means the combo will drag down the performance of the amplifier some.

As a DAC, it falls in the failing (red) category of all DACs tested to date:

Best stereo DAC measured 2020.png

Noise performance is decent:
IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Toslink Digital Dynamic Range Audio Measurem...png


Intermodulation+noise test is disappointing:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Toslink Digital IMD Audio Measurements.png


The upper line in orange is a phone dongle! The SA3 hugs that performs like it is related to it which it should not be.

Jitter performance looks better than it is due to high noise floor potentially hiding other spurious tones:

IOTAVX SA3 AUDIOPHILE INTEGRATED STEREO AMPLIFIER Toslink Digital Jitter Audio Measurements.png


So overall the DAC portion is barely a match for the amplifier. If the amp gets the grade B, the DAC gets a C+.

Conclusions
It is nice to see a fresh take on the integrated stereo amplifier from IOTAVIX. The SA3 looks attractive, has good feature set including many inputs from digital to analog and takes up little space. You can nicely put it under your monitor, add a couple of speakers and be in business.

You don't get to brag its measured performance but what is there "is not broken" which is often an accomplishment in world of audio. Performance is solid across the board with the DAC trailing a bit. I would happily use it in a secondary system.

Overall, I am going to recommend the IOTAVIX SA2 amplifier.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Every day I am in the garden, digging holes, removing rocks and weed and planting until my back can't take it anymore. Then I come inside and do these reviews. I am thinking this definitely qualifies for overtime. So even if you have donated before, you owe me an extra 50% in donations : https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

Xulonn

Major Contributor
Forum Donor
Joined
Jun 27, 2018
Messages
1,197
Likes
3,127
Location
Boquete, Chiriqui, Panama
#2
Finally! Thanks Amir. Several members have been waiting for this one. Bypass the built in DAC and use a Topping D10 or similar external DAC, and you've got an even better setup, and still for a good price. Like the VTV Hypex amplifiers, minor issues don't spoil an excellent bargain - especially with free shipping to the U.S. Here's the interior photo from the IOTAVX website.

IOTAVX Integrated.jpg


I wouldn't be concerned about the DAC performance, but I'm a bit surprised that it wasn't better. No bragging rights, but it should sound fine. If the same wonky DAC performance exists with the IOTAVX 7.1 4K AVP with HDMI input, I just might keep my Topping DX7s DAC/HA for two-channel music listening. Hopefully someone in the U.S. will buy an IOTAVX AVP and send it to you for measurement.

I paid for the AVP with PayPal, and it took a week for Ian to ship it out via DHL. Good tracking info and updates. It took only four days for it to get to my forwarder in Miami, and looks like it will be about ten days to get from from Miami to Panama. Below is a photo of the AVP back panel. I will report on my impressions of it in a week or so.

IOTAVX 71 Rear.jpg


I think IOTAVZ will be a good, solid line of entry-level audiophile gear, especially if we can get Ian to tweak the DAC section. Their 7-channel AV Amplifier looks good too with about twice the power per channel as the integrated and balanced XLR inputs.

IOTAVX 7 Ch Amp.jpg
 
Last edited:

Xulonn

Major Contributor
Forum Donor
Joined
Jun 27, 2018
Messages
1,197
Likes
3,127
Location
Boquete, Chiriqui, Panama
#5
For that matter, I'd skip the integrated and got their power PA3 amp instead for 100 pounds less.
A IOTAVX PA3 would be great match for the $130 Topping E30 DAC/Pre with it's remote control - unless you still have other analog sourses and a need traditional preamplifier functions with input switching and/or active gain.

Also, expect confusion as both IOTAVX and Topping offer amplifiers with the model number "PA3".
 

Xulonn

Major Contributor
Forum Donor
Joined
Jun 27, 2018
Messages
1,197
Likes
3,127
Location
Boquete, Chiriqui, Panama
#6
Interesting, their multichannel offerings used to be sold under Nakamichi brand.
That's one of the reasons I felt confident to buy the AVP since it doesn't yet have a track record. I think the current IOTAVX products are upgraded from the older designs, and IOTAVX actually has downloaded manuals for the Nakamichi versions as "legacy" products.

In fact the www.nakamichi.co.uk URL redirects to IOTAVX website.

Here is a photo of the back panel of the Older Nakamichi AV1:

Nakamichi AVP1.jpg
 
Last edited:

Koeitje

Addicted to Fun and Learning
Joined
Oct 10, 2019
Messages
607
Likes
600
#7
The bad DAC performance has me worried, but somehow I knew that would happen. I contacted IOTAVX a while back through their website and asked if they had any specifications on their 7.1 processor. Because neither to website nor manual had any. They never got back to me. Sucks, because it was on the top of my list of pre-amps.
 

Rifmon

Member
Forum Donor
Joined
Mar 24, 2020
Messages
59
Likes
44
#8
Wow. Thanks so much Amir! I’m glad to see it get a recommendation despite a few shortcomings. The DAC can be circumvented easily. As an overall package and price point it’s a good deal. The rating at 4 ohms isn’t quite as advertised but still not bad. I would be buying the SA3 and PA3 together so the combo may produce slightly better results.

I’m going to need to think about this as I have other options on my short list. But your analysis is very much appreciated!

I wonder why other manufactures don’t assemble their amps with similar symmetry since it has such a good affect on crosstalk? Plus it’s balance when you pick it up.
 
Joined
Dec 9, 2019
Messages
94
Likes
68
#10
That's one of the reasons I felt confident to buy the AVP since it doesn't yet have a track record. I think the current IOTAVX products are upgraded from the older designs, and IOTAVX actually has downloaded manuals for the Nakamichi versions as "legacy" products.
Yes, but you should still realize that those "Nakamichi" products had nothing to do with the real Nakamichi gear from the 80s. All was made by Chinese manufacturer ToneWinner. Internally the SA3 seems to have nothing similar to their Nakamichi AV1 preamp. The SA3 should have earned a headless panther, but I think the low price saved it.
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
3,352
Likes
1,946
Location
Tarragona (Spain)
#12
Joined
Nov 9, 2019
Messages
83
Likes
50
#13
I'm not surprised about the DAC. I could not measure it and it sounds good but when you turn the volume way up it is noisier than the line input.
It also switches with relays if the bitrate changes.

A longer press on the volume knob selects the bass/trebble/balance settings. Really long press resets it.

One thing I'm not happy about is the non grounded power supply. It uses a small switching powersupply as standby power, under the metal shield see picture above and it leaks some voltage to the chassis. I grounded it myself with a wire to ground and the phono earth connector.
 

Matias

Addicted to Fun and Learning
Forum Donor
Joined
Jan 1, 2019
Messages
735
Likes
880
Location
São Paulo, Brazil
#14
Topping E30 + VTV NC252MP would be about 630 usd, a little more than the 500 usd here, and would perform so much better.
 

wje

Active Member
Forum Donor
Joined
Feb 13, 2020
Messages
250
Likes
303
Location
Virginia
#16
Topping E30 + VTV NC252MP would be about 630 usd, a little more than the 500 usd here, and would perform so much better.
How frequent are the increments in the Topping E30? When I had my Cambridge Audio 851N network player, I used the digital preamplifier section to power my Cambridge 851W power amplifier. The increments were too far apart - making the fine tuning of volume to suit your needs a bit hard. My intent was just to use the IOTAVX as a preamplifier only - along with Khadas Tone Board DAC. However, in waiting on the review, an Emotiva XPS-1 came along for a good price, so I opted for that. Not sure where I'll use the SA3 just yet - maybe in a 2nd system at some point.
 
Joined
Apr 25, 2019
Messages
48
Likes
70
#17
I wonder how the similarly priced Yamaha S501 fares.
I actually wonder how something like Denon AVR-X1600 will fare ($100 more, but way, WAY more features and higher power), given that 3600 turned out to be very good and there are some reasons to assume that lower tiered models aren't really that different.
The still prevalent audiophool argument about separates being necessarily better than all-in-ones could really use a good spanking.
 

BDWoody

Major Contributor
Forum Donor
Joined
Jan 9, 2019
Messages
2,168
Likes
4,122
Location
Mid-Atlantic, USA. (Maryland)
#18
The prevalent audiophool argument about separates being necessarily better than all-in-ones could really use a good spanking.
I think they might enjoy it too much...

They seem to like punishing their wallets, and they are already submitting to the marketing powers that be. Might be more of a motivator after all.

New deal...$20k DAC and the spanking you clearly need. Probably sell like gangbusters.
 

Similar threads

Top Bottom