This R2R tube DAC is completely bonkers! Linear Tube Audio Aero review

Summary

The Linear Tube Audio Aerod DAC, priced at $3,950, is a unique blend of non-oversampling R2R design and tube amplification. It prioritizes simplicity with limited inputs and no DSD support, focusing on natural sound quality. Despite lacking in detail retrieval compared to multi-bit and Delta Sigma DACs, the Aerod excels in tonality and musical enjoyment. It offers a balanced sound with rich mids and a creamy texture, making it an excellent choice for those seeking a warm, immersive listening experience without the high-end price tag.

Takeaways

• 🎧 The script discusses the early decisions audio design engineers must make when creating a new product, such as choosing between tube or solid-state circuitry and different DAC designs.
• 📻 Tubes are favored for their richness and smoothness, while solid-state is known for clarity and precision in audio equipment.
• 🔊 The debate between non-oversampling R2R DAC designs and oversampling Delta Sigma DACs is highlighted, with opinions varying on which provides a more natural or clearer sound.
• 💡 Linear Tube Audio is a company known for high-quality tube amplifiers and has ventured into digital realm with their AERIS DAC, combining a non-oversampling R2R design with tubes.
• 💸 The AERIS DAC is priced at $3,950, making it more expensive than some well-regarded DACs and using a rare combination of technologies.
• 🛠️ The AERIS DAC is designed with a simple signal path but includes complex internal circuitry to ensure high-quality digital-to-analog conversion and a stable power supply.
• 🔌 The AERIS has limited inputs (USB, Optical, and Coaxial) and supports sample rates up to 192 kHz, lacking DSD and higher output rates like 352.8 or 384 kHz.
• 📈 The AERIS uses an active current-to-voltage conversion stage to maintain performance across different frequencies, differing from the passive conversion stages in many DACs.
• 🎶 The output stage of the AERIS utilizes Linear Tube Audio's well-regarded zOTL design, offering a transparent, clean tube sound with the benefits of tube richness.
• 🏆 The AERIS excels in tonality and natural sound, providing a rich and full sound without being overly warm or smooth, striking a balance between tube warmth and solid-state clarity.
• 🎵 While the AERIS may not match some other DACs in terms of detail retrieval and resolution, it offers a more relaxed, enjoyable, and immersive listening experience.

Q & A

What are the early decisions an audio design engineer has to make when creating a new product?

The early decisions include choosing between tubes or solid-state circuitry, and deciding on the type of DAC design such as non-oversampling, oversampling R2R, or Delta Sigma.

Why are tubes preferred in some audio designs?

Tubes are favored for their richness and smoothness, offering a warm and natural sound quality.

What is the advantage of solid-state circuitry in audio design?

Solid-state circuitry is known for clarity and precision, providing a more defined and accurate sound.

What does the term 'non-oversampling' refer to in the context of DAC design?

Non-oversampling refers to a DAC design that does not use additional sampling rates beyond the original signal's to improve audio quality.

What is the significance of the Analog Devices A1865 DAC chip used in the Linear Tube Audio Aerod DAC?

The A1865 is a non-oversampling R2R DAC chip known for high-quality digital-to-analog conversion, used in premium audio products.

Why is power supply design important in a DAC like the Linear Tube Audio Aerod?

A carefully designed power supply ensures a stable and clean power source, preventing interference with the digital decoding or analog output stages.

What is the role of the current-to-voltage conversion stage in a DAC?

The current-to-voltage conversion stage is crucial as it adapts to provide ideal performance levels, ensuring the output stage receives a variable voltage signal instead of a current.

How does the output stage of the Linear Tube Audio Aerod DAC utilize tubes?

The output stage uses a well-regarded ZOTL design from Linear Tube Audio, providing a transparent, clean, and tube-like sound with clarity and resolution.

In what ways does the Linear Tube Audio Aerod DAC differ from other DACs in the market?

The Aerod DAC differs by using a combination of non-oversampling R2R design and tubes, focusing on simplicity in the signal path, and offering a natural and tonally rich sound.

What are some of the trade-offs when choosing a DAC like the Linear Tube Audio Aerod over others?

While the Aerod may not offer the highest levels of detail retrieval and resolution compared to multi-bit or Delta Sigma DACs, it excels in tonality, musical enjoyment, and natural sound.

How does the Linear Tube Audio Aerod DAC compare to more expensive options in terms of tonality and musical enjoyment?

Despite being less expensive, the Aerod offers tonality and musical enjoyment comparable to much pricier DACs, making it a strong contender in the market.

Outlines

00:00

🔊 Audio Design Choices and Linear Tube Audio's AERoD Deck

The script discusses the critical early decisions an audio design engineer must make when creating a new product, such as the choice between tube or solid-state circuitry and the type of DAC design. It introduces the Linear Tube Audio AERoD deck, which combines a non-oversampling R2R DAC design with tubes, a rare combination. The AERoD deck is noted for its simplicity, with limited inputs and sample rates, and its high cost compared to other well-regarded decks. The company's focus on high-quality digital-to-analog conversion, careful circuit design, and a stable power supply is highlighted, as well as their innovative approach to current-to-voltage conversion and the use of their renowned ZOTL tube design for the output stage, aiming for a natural and clear sound.

05:00

🎧 AERoD Deck's Performance and Comparison with Other DACs

This paragraph delves into the performance aspects of the AERoD deck, emphasizing its tonality and natural sound quality. It discusses the deck's ability to balance richness and clarity, and its strong point in delivering a natural and full sound. The script compares the AERoD with other DACs, noting that while it may lack in micro-details and resolution compared to multi-bit and Delta Sigma DACs, it excels in musical enjoyment. The AERoD's performance across different inputs is also highlighted, with the deck maintaining consistent quality regardless of the input source. The discussion includes a comparison with a mysterious competing deck, noting the AERoD's strengths in tonality and soundstage size, despite some minor shortcomings in detail retrieval.

10:01

💽 AERoD Deck's Positioning in the Market and Conclusion

The final paragraph wraps up the discussion by reflecting on the AERoD deck's market positioning and its potential impact on the DAC market. It acknowledges the initial skepticism about Linear Tube Audio venturing into the digital realm but praises the AERoD for its tonal accuracy and musical enjoyment, positioning it as a strong contender among more expensive options. The script concludes by comparing the AERoD with the more costly C Dave and M Scala setups, noting that while the AERoD may not match in terms of staging and separation, it offers a tonality and musical experience that rivals these high-end systems at a fraction of the cost. The review ends with a recommendation for those seeking a simple, high-quality R2R tube DAC and an invitation for viewers to explore the Linear Tube Audio offering.

Keywords

💡Audio Design Engineer

An audio design engineer is a professional who specializes in the design and development of audio equipment and systems. In the context of the video, they are responsible for making early decisions on the type of circuitry and digital-to-analog conversion (DAC) design to use in creating a new product. The script mentions the dilemma of choosing between tubes and solid-state circuitry, highlighting the importance of the engineer's role in determining the sound quality and characteristics of the final product.

💡Tubes

Tubes, or vacuum tubes, are electronic components that were once widely used in audio amplifiers for their warm and rich sound quality. The script discusses tubes in the context of their use in audio equipment, suggesting that they contribute to a smooth and rich audio experience, although they may lack the clarity and precision of solid-state circuitry.

💡Solid-State Circuitry

Solid-state circuitry refers to electronic circuits that use transistors and diodes instead of vacuum tubes. In the video, solid-state is praised for its clarity and precision, which are desirable traits for audio reproduction, especially in DACs where accurate signal decoding is crucial.

💡Non-Oversampling DAC

A non-oversampling DAC is a type of digital-to-analog converter that does not increase the sample rate of the digital signal before converting it to an analog signal. The script contrasts non-oversampling DACs with oversampling and Delta Sigma designs, suggesting that non-oversampling DACs may offer a more natural and lifelike sound but might lack in clarity and definition.

💡Oversampling DAC

Oversampling DACs are designed to increase the sample rate of the digital signal before converting it to analog, which can improve the sound quality by reducing aliasing and noise. The video mentions oversampling DACs as an alternative to non-oversampling designs, indicating that they might offer better clarity and definition but could be perceived as less natural.

💡Delta Sigma DAC

Delta Sigma DACs are a type of oversampling DAC that uses a specific modulator to convert digital signals to analog with high precision. The script suggests that Delta Sigma DACs are favored by some for their ability to accurately decode signals, implying they might offer superior sound quality in terms of detail and texture.

💡Linear Tube Audio

Linear Tube Audio is the company featured in the video, known for producing high-quality tube amplifiers. The script discusses their venture into the digital realm with the AERIS DAC, which combines tube technology with a non-oversampling R2R DAC design, showcasing the company's ability to innovate and adapt to new technologies.

💡R2R DAC Chip

An R2R DAC chip is a type of DAC that uses a resistor ladder network to convert digital signals to analog. The script highlights the Analog Devices AD1865 R2R DAC chip used in the Linear Tube Audio AERIS, emphasizing its high-quality digital-to-analog conversion capabilities and its use in premium audio products.

💡Power Supply

The power supply in audio equipment is crucial for maintaining the stability and quality of the audio signal. The video describes how Linear Tube Audio paid great attention to the power supply in their AERIS DAC, ensuring a clean and stable power source that separates the analog and digital sides of the circuit.

💡Current to Voltage Conversion

Since most DAC chips output a variable current, a current to voltage conversion stage is necessary to match the output to the needs of the rest of the audio system. The script explains that Linear Tube Audio developed an active conversion system for their AERIS DAC to ensure optimal performance levels, indicating the importance of this conversion process in achieving high-quality sound.

💡ZOTL Design

ZOTL is a specific design of tube output stage used by Linear Tube Audio in their products, including the AERIS DAC. The script mentions ZOTL circuits for providing a transparent, clean, and almost solid-state-like tube delivery with the benefits of tubes, such as naturality and fluidity, without sacrificing clarity or resolution.

💡Soundstage

Soundstage refers to the perceived spatial dimensions of the audio, including width and depth. The video uses soundstage as a criterion for comparing different DACs, noting that the AERIS DAC produced an exceptionally natural soundstage, which is a strong point of the product.

💡Tonality

Tonality in audio refers to the overall character or quality of the sound, including its richness and fullness. The script emphasizes the AERIS DAC's tonality as a standout feature, describing it as exceptionally natural and perfectly balanced, which contributes to the musical enjoyment it delivers.

💡Resolution

Resolution in the context of audio refers to the level of detail and clarity with which fine textures and micro-dynamics are reproduced. The video acknowledges that while the AERIS DAC may not match some competitors in resolution, it does not lack in delivering a satisfying listening experience, suggesting that resolution is a matter of personal preference.

💡Musical Enjoyment

Musical enjoyment is the subjective experience of pleasure derived from listening to music. The script positions the AERIS DAC as a product that prioritizes musical enjoyment, suggesting that it may sacrifice some technical specifications for a more immersive and enjoyable listening experience.

Highlights

The debate between tube and solid-state circuitry in audio design for richness and smoothness versus clarity and precision.

The choice between non-oversampling, oversampling, and Delta Sigma DAC designs for natural sound versus clarity and definition.

Linear Tube Audio's success in creating high-resolution tube amplifiers and their venture into digital realm with the AERoD DAC.

The AERoD DAC's high price point compared to other well-regarded DACs and its unique combination of non-oversampling R2R design and tubes.

The simplicity of the AERoD DAC's design with limited inputs and sample rates, focusing on high-quality digital-to-analog conversion.

The importance of a high-quality power supply in the AERoD DAC to ensure clean and stable power for both digital and analog sides.

The AERoD DAC's use of the Analog Devices AD1865 R2R DAC chip found in premium products for high-quality conversion.

The development of an active current-to-voltage conversion system in the AERoD to ensure consistent performance across frequencies.

The use of Linear Tube Audio's renowned zOTL tube design in the AERoD's output stage for a transparent and clean sound.

The AERoD DAC's performance across different inputs, emphasizing the importance of source quality for optimal sound.

The AERoD's strong tonality and natural sound as its standout characteristic when compared to other DACs.

The AERoD's balance between richness and clarity, avoiding being overly warm or clinical in sound reproduction.

The AERoD's performance in soundstage size and depth, compared to other DACs like the Eil Plus MIB and LV Harmony.

The AERoD's slightly lower performance in detail retrieval and resolution compared to multi-bit and Delta Sigma DACs.

The subjective nature of preferring detail versus a relaxing and immersive musical experience with the AERoD.

The AERoD's musical enjoyment and its comparison with more expensive DACs like the Chord Dave and M Scaler.

The surprising competition between the more affordable 'mystery' DAC and the higher-priced AERoD in musical enjoyment.

The AERoD's tonal accuracy and naturalness, which are considered as good as more expensive options without the price tag.

The reconsideration of Linear Tube Audio's venture into digital with the AERoD, which may have upended market expectations.

Transcripts

when an audio design engineer starts

making a new product they have to begin

with some very early

decisions should they use tubes or solid

state circuitry tubes are great for

richness and smoothness solid state is

known for clarity and

precision should they use a non-

oversampling rard deac design maybe an

oversampling arto design or maybe go

fullon oversampling Delta Sigma some

people feel that the r deck sound more

natural more lifelike some will say

especially the non oversampling ones

others would say that those lack Clarity

and definition and attack and favor

Delta Sigma saying that that's the only

way to properly and accurately decode

the signal so does that mean that a non

over sampling AR Our Deck using tubes

will be a mushy overly warm and

inaccurate Sonic

[Music]

disaster let's find

out linear tube audio is a company built

on the foundation of producing lovely

resolving and clear sounding tube amps

in other words they've proven themselves

incredibly capable of making wonderful

Analog Devices well now they've gone and

dabbled in the digital

realm let's talk about why maybe they

should have stuck to their Lane at

$3,950 the linear tube audio aerod deck

is not cheap it's more expensive than

other very well regged decks like the

idrasil the LV Harmony deck the

cord cutest and the Hollow Spring kte

it's also using a combination of a non

oversampling art design and tubes which

is very rarely done if at all it's also

seemingly a very simple deck there's no

oversampling there's no digital

filtering there's no feedback it's only

got USB Optical and coal inputs and it

will only accept sample rates up to 192

khz so there's no DSD and there's no

using HQ player to Output 368 or 78

khz it's all very very simple on the

surface the linear tube Arrow looks like

a ton deaf entrant into a DAC Market

that's full of Swiss army knife do

everything Dax sometimes though doing

the simple thing is more difficult than

doing something

complex and sometimes it's also

better by keeping everything really

simple in the signal path linear tube

audio have produced a wonderfully

natural sounding Dack but that's been

achieved through some very careful

decision- making and some very careful

circuit design in other areas firstly if

they weren't going to apply a whole lot

of filtering and adjustment of the

signal coming out of the digital stage

of the deck then they had to begin with

very high quality digital to analog

conversion and they achieved this with

the selection of The Analog Devices

a1865 Dack chip that's a non-

oversampling r2r Dack chip that's used

in some super premium products next they

paid great attention to the power supply

in the arrow and that was to ensure that

they separated the analog and the

digital sides of the circuit and

produced a very stable and clean power

supply that wasn't going to muck up

either the digital side of the decoding

or the analog output side of things if

you want to know more about that you can

read up more on the linear tube audio

website I'll link in the description

down

below something else to consider is that

DAC chips most DAC chips and

particularly the one used here here

output a variable current output in

other words the voltage stays fixed and

the current does the varying with the

signal but what the output stage needs

is a variable voltage and so most decks

will need to have what they call a

current to voltage conversion stage and

if that's not handled well the

performance of the Dack can vary at

different frequencies and so instead of

the passive conversion process that's

used in many decks linear tube audio

developed a more complex active system

that's going to adapt itself to make

sure that you're always getting the

ideal performance levels out of the deck

chip and so in other words this deck is

really complex on the inside so it can

be really simple on the outside and then

after all of that the output stage in

the arrow the bit that interfaces with

your preamp your integrated amp or your

headphone amp that uses

tubes and specifically it runs through

one of linear tube audio's very well

regarded zotl designs

[Music]

I'm not going to go into depth on that

one here but I've talked a lot about it

in the linear tube audio mz3 review that

you can check out after this if you want

to but the long and the short of it is

that the zotl circuits provide a

wonderfully transparent clean and almost

solid state like tube delivery but with

all the benefits of tubes as well so the

naturality the fluidity the ease of

listening but Clarity resolution and no

sense of thickness

so that's the output stage in the arrow

now of course the quality of the inputs

noise rejection galvanic isolation all

of that came into play as well for

linear tube audio and so you'll find

that the inputs on the aod deck all

perform equivalently whether you're

running USB in whether you're running

Optical in or coaxial in each of those

can be equally as good assuming that the

source is equally as good as well in

other words if you've got a crappy USB

output on your device it may sound

better using a coxal output from that

device but that's about the Upstream

device not about the arrow deck if all

things are equal the arrow performs

equally across all

inputs when I compared the arrow

recently to a bunch of other excellent

decks the characteristic that

consistently stood out to me as being

the strong point of the arrow was a

sense of tonality and tber in other

words how natural everything sounded

from this deck and that is to say

exceptionally natural it has a sense of

richness and fullness to the sound but

it's in just the right amount everything

sounds natural from this deck not rich

or warm and not clinical or sterile it

finds the perfect balance point when

compared to other decks like the

aforementioned eil plus MIB the LV

Harmony deck and another mystery deck

that I'm going to keep a mystery for now

the arrow produced the best sound stage

size of all of them when considering

both width and depth of the Sound Stage

the mystery deck did Stretch A little

bit wider but it wasn't larger overall

the arrow also comfortably delivered the

most pleasing tonality across the board

but it wasn't a complete win for the

arrow on all counts one area that I

consistently hear R2 dexs fall a little

bit short of their multi-bit and Delta

Sigma cousins is in things like dto

retrieval and resolution and that's true

of the arrow to you can hear that it's

not quite delivering the same levels of

texture detail and very fine sort of

micro resolution micro textures whatever

you want to call them it's not quite

matching a deck like the IG in that

regard if you weren't comparing them

side by side you would never think the

arrow was lacking anything but that's

why I compare them side by

side having said that whether that

difference is a bad thing is very

personal some people crave every last

little bit of insight into the music and

I get that cuz I love that too but

there's others that are more interested

in a relaxing enjoyable and immersive

musical experience and it's not about

the detail for others still

you might have an aggressive system with

bright speakers or a room with lots of

high frequency reflective surfaces and

you might actually need a deck that just

tames things a little bit in summary

what I'm saying here is that the right

deck and the right levels of texture and

detail depend on you your system the

room you're listening in even your

preferences on the day sometimes and so

yes the arrow is not quite as resolving

and textured as some other decks but

it's definitely not lacking it's

definitely not overly warm or rich or

smooth and so if you are looking for a

deck that takes just a little bit of the

edge off the sense of attack and high

frequency energy and detail and texture

the arrow is

[Music]

magnificent so the arrow isn't going to

win any medals for Det retrieval but

it's absolutely going to win medals for

the sheer musical enjoyment it delivers

and so if musical enjoyment is where

it's at for you the arrow is one you

should look

at of the four decks that I tried in my

deck off with the arrow only the mystery

deck was truly competing with the arrow

for my overall enjoyment of the music

you'll have to subscribe if you want to

know what that mystery deck is because I

haven't finished forming my full

thoughts on it and I don't want to jump

the shark on that one until I spent more

time with it however it is important to

know that the arrow was the most

expensive deck in the deck off by the

end of my listing and comparisons

between all four decks it came down to a

decision for me between the arrow and

the Mystery deck as to which one I

thought was best and that decision

actually came down to which amp which

music track and which headphones I was

using with the headphone 2 I prefer the

mystery deck but with the susar unveiled

yes they're here I prefer the linear

tube audio aod deck and that's because

the arrow delivered a little bit more

weight and body to the sound that really

helps the unveiled to sound their best

what was slightly off-putting though was

that the much cheaper mystery deck was

going head head to head with the more

expensive arrow and so at that point I

decided to pack things up put everything

away for the night because I was getting

tired and continue building my

impressions of the arrow back here in my

office for the next couple of days and

I'm so glad I

did once I was back in my office I was

able to compare the arrow to the core

Dave deck I had both of them running

into the bur audio Voyager amp and

driving the susar

unveiled on a rock track like wonder

wall the top end the treble is crisper

from a deck like the Dave but that can

actually be too much sometimes depending

on the track and the setup that you're

using adding the M scale out of the mix

does help with this a little bit but it

also blows the budget way out of the

water when we're comparing it to the

aerody deck I mean the Dave is already 3

to four times the price of the $4,000

Arrow so adding the M Scala really

didn't make sense here continuing with

just the Dave and the arrow in other

words no M scaler in the mix I found

that the base had a little bit more

weight and presence to it from the Dave

and the separation of sounds is a bit

stronger too in comparison the arrow is

a little bit thick sounding and that

helps the Dave to produce a greater

sense of width and separation in The

Sound Stage whereas the arrow tends to

focus you WI a little bit towards the

middle towards the mid-range towards the

main solo vocalist or instrumental which

could be a good thing it all depends on

you switching to a simpler track with

better recording like perfect blue

buildings show that the Dave also

delivers a little bit more sense of

nuance and Detail in the high end sounds

like high hats and symbol hits there's a

touch more texture in the vocals too but

before you think that this is a route of

the Arrow by the Dave we do need to

consider a couple of things firstly a

reminder that the Dave is 3 to four

times the price of the arrow it should

be vastly better and then secondly the

tber or the tonality of the arrow is

flat out perfect the arrow is noticeably

a little bit creamier through the mids

and that actually makes it more akin to

the optimal version of the Dave with the

m scaler attached in other words for

those not chasing extreme micro details

and nuance and every last texture and

piece of clarity in the sound the arrow

is delivering a Dave like level of tber

and tonality without the Dave in the

mcalea price tag it doesn't quite match

the Dave in terms of staging separation

of sound focus of the image but it's

tonality naturalness and tber is as good

as anything I've heard at any price is

as good as anything I've heard at any

price and in other words the linear tube

audio aod deck is I think the best deck

I've heard short of far more expensive

options like the cord tt2 the Holo audio

make kte and of course the C Dave you

might be losing a tiny bit of resolution

but you're getting a double dosing of

tonal wonder and musical

enjoyment I said earlier that I thought

linear tube audio maybe should have

stuck to their Lane and continued

producing analog product only and that's

because they might have just completely

upended the market and our expectations

of Dex within the market so I take that

back I'm glad they went rogue if you

want to go Rogue as well and have

yourself a wonderfully simple NOS R2

tube D I'll put links down below where

you can go through the linear audio and

check it out for yourself as always I

want to say a huge thanks to channel

members to channel patreon members and

to those of you that leave super thanks

here on videos like this one if you like

the general sound of the tonality and

tambal accuracy of the linear tube Arrow

but you want something even better I'll

put my link up here to the cord Dave

review for now though Havey listening be

kind to each other and I'll see you here

next time on passion for sound