3e Audio A5 Stereo Amplifier Review

[jlx]

So my stepped attenuator increments in .5db increments, as indeed does the digital volume control on my DAC.

So the difference is about 4 clicks on the attenuator ... or four presses on the DAC volume control. So something, but indeed not that much.

Someone will maybe chip in about how it all relates to speaker sensitivity! Mine are 90db so A5 a safe choice (for me).

first the simple
100 watts delivered to a speaker= 20db of output gain so 90db (at 1 watt/1 meter) + 20db=110 db peak, it is extremely unlikely a single speaker can hit these levels & that's ear damaging territory anyway
this is at 1 meter distance

the complicated
add 5db for a second speaker when measured at your seat,
subtract about 10db for a 4 meter distance (in a medium sized room) from your seat to the speakers,
add a few db for room gain.. presto
a rough shortcut is if a speaker is 90db at 1 watt/1 meter, when all is said and done seated at 4 meters you will get a pinch under 90db measured spl total ( maybe 87?db or so) with both speakers running at 1 watts feeding each. That is reasonably loud.
Most folks listen in the 70-80db range, and above 80db for brief periods. These are sustained average levels, not the occasional peaks.

the biggest bu** sh*** numbers put out by manufacturers are max power handling, speaker impedance and sensitivity. It is very common to measure and find a speaker sold as 90db @2.83V is really 86db or 84db or whatever. A listed 8 ohms can easily be 5.5 ohms nominal. They often just make up a number.
Also an 86db 2.83V/ 1 meter speaker specification is REALLY around 83db at 1 watt/1 meter (so about 2.0 V)

I measured an A5 on an actual 86.5db, 4 ohm nominal (for real) bookshelf speaker pair and got 96db peaks (c weighted) at 8 ft distance in a 13 x 16ft room. I was near the amps max but did not clip itso I still had a bit of power left to use. It was very, very loud.

Exactly, and yet with both motors at the same rpm, the same transmission, and the same gear, you will reach exactly the same top speed. Neither will be faster, even if it has 10 times the power.

And that's exactly the apt example for the A5 and A7.
The input sensitivity is the same for both devices. But the internal gain (the amplification factor in the small-signal processing before the TPA325x) is 3 dB higher. And thus, the achievable volume can also be higher if enough power is available. This is also the correct approach by 3e Audio.
And back to the example above, with the A7, it's as if you shift up a gear = higher speed.

essentially correct, although the car analogy is not one I would normally make (and in fact I did not initially make, I just ran with it as best I could) the A7 will act effectively as another gear shift., so a higher speed for a given throttle input. The A7 will be 2.2db louder for the same given source signal .5V, 1.1V or whatever it may be up to the max output achieved with a 1.75Vrms signal (for a direct A5 to A7 comparison due to the same input sensitivity)

 

[Roland68]

first the simple
100 watts delivered to a speaker= 20db of output gain so 90db (at 1 watt/1 meter) + 20db=110 db peak, it is extremely unlikely a single speaker can hit these levels & that's ear damaging territory anyway
this is at 1 meter distance

the complicated
add 5db for a second speaker when measured at your seat,
subtract about 10db for a 4 meter distance (in a medium sized room) from your seat to the speakers,
add a few db for room gain.. presto
a rough shortcut is if a speaker is 90db at 1 watt/1 meter, when all is said and done seated at 4 meters you will get a pinch under 90db measured spl total ( maybe 87?db or so) with both speakers running at 1 watts feeding each. That is reasonably loud.
Most folks listen in the 70-80db range, and above 80db for brief periods. These are sustained average levels, not the occasional peaks.

the biggest bu** sh*** numbers put out by manufacturers are max power handling, speaker impedance and sensitivity. It is very common to measure and find a speaker sold as 90db @2.83V is really 86db or 84db or whatever. A listed 8 ohms can easily be 5.5 ohms nominal. They often just make up a number.
Also an 86db 2.83V/ 1 meter speaker specification is REALLY around 83db at 1 watt/1 meter (so about 2.0 V)

I measured an A5 on an actual 86.5db, 4 ohm nominal (for real) bookshelf speaker pair and got 96db peaks (c weighted) at 8 ft distance in a 13 x 16ft room. I was near the amps max but did not clip itso I still had a bit of power left to use. It was very, very loud.


correct, the A7 will act effectively as another gear shift., so higher speed. It will be 2.2db louder for the same given source signal .5V, 1.1V or whatever it may be up to the max output achieved with a 1.75Vrms signal (for a direct A5 to A7 comparison due to the same input sensitivity)

Okay, you're one of those people who doesn't want to understand.
Just look at the manual.
The A7 has a higher internal gain factor for the power amplifier.
And to put it simply, the A7 amplifies the input signal by 3 dB more than the A5.
That's why it can play 3 dB louder than the A5. Nothing else.

 

[jlx]

Okay, you're one of those people who doesn't want to understand.
Just look at the manual.
The A7 has a higher internal gain factor for the power amplifier.
And to put it simply, the A7 amplifies the input signal by 3 dB more than the A5.
That's why it can play 3 dB louder than the A5. Nothing else.

View attachment 441373

It seems you are one of those people that doesn't quite get what the internal input buffer stage gain means that you have circled. That is not the amps total gain

all that matters is that for max output, you need 1.75Vrms for both units (for a single ended input obviously)
So for the A5 vs the A7's 150W vs 250W max power out at 4ohm spec IS NOT a 3db gain as you state, it is 2.2db of additional output power. So that is the A7's additional gain over the A5.
As the sensitivity is the same, the A7 will have about 2.2db additional output for any given input signal up until max out

if it had 3db of additional amp gain the A7 would list max out as 300 watts, not the 250w given

 

[harkpabst]

Voltage gain
A5: 20 * log(√(150 W * 4 Ω) / 1.75 V) ≈ 22.92 dB
A7: 20 * log(√(250 W * 4 Ω) / 1.75 V) ≈ 25.14 dB
Gain difference: 2.22 dB

Precondition: Sensitivity an power ratings given by 3e Audio are correct. Let's check the results using the 8 Ω ratings.

A5: 20 * log(√(80 W * 8 Ω) / 1.75 V) ≈ 23.20 dB
A7: 20 * log(√(140 W * 8 Ω) / 1.75 V) ≈ 25.63 dB
Gain difference: 2.4 dB

Not sure what we need to talk about here. The 23 dB/26 dB numbers most certainly are overall voltage gain. Everything else is about rounding errors and measurement precision.

 

[jlx]

Voltage gain
A5: 20 * log(√(150 W * 4 Ω) / 1.75 V) ≈ 22.92 dB
A7: 20 * log(√(250 W * 4 Ω) / 1.75 V) ≈ 25.14 dB
Gain difference: 2.22 dB

Precondition: Sensitivity an power ratings given by 3e Audio are correct. Let's check the results using the 8 Ω ratings.

A5: 20 * log(√(80 W * 8 Ω) / 1.75 V) ≈ 23.20 dB
A7: 20 * log(√(140 W * 8 Ω) / 1.75 V) ≈ 25.63 dB
Gain difference: 2.4 dB

Not sure what we need to talk about here. The 23 dB/26 dB numbers most certainly are overall voltage gain. Everything else is about rounding errors and measurement precision.

are we sure its the overall amp gain?

the A5 spec gain is given as 23/26 for the1.75Vrms input
your numbers are 22.92 4 ohm and 23.2db 8 ohm, so a rounded 23db
where is the 26db of voltage gain at the output?

the A7 spec is gain is 26/29db for the 1.75Vrms input
your numbers are 25.14 and 25.63db for the 4 ohm and 8ohm, so a rounded 26db
where is the 29db of voltage gain at the output?

we are talking about that for both amps the same given input level will provide a greater output from the A7 of around 2.2db at 4 ohms (and 2.4db at 8, but I was too lazy to check that) not the 3db that was claimed

using their max 1% thd output levels we also get 2.2db at 4 ohms and 2.4db at 8 ohms not the 3 ohms this gent is stating. This is a rounding error?

is it coincidence that the rear se input gain switch is listed as 25 and 28.5 for both amps on page 4 (although the picture above that spec is the A5, the manual is for both units so that could be the spec for the A7 switch , this is somewhat vague)
Or is it possible that the 23/26db gain spec is for the A5 (and the 26/29db for the A7) rear SE gain switch as I maintain?

 

[harkpabst]

My main point is: You should not exaggarate your dispute about 3 dB or 2.2 dB, because you are both just trying to explain the same thing. With two power amplifiers, both driven within their operating limits, and everything else being equal, the observed SPL for any given volume setting on the pre-amp does not depend on the maximum power output of each amp.

That's about the shortest description I can come up without being to sloppy. And I think you both agree on that. Let's not worry about the finer details too much.

the A5 spec gain is given as 23/26 for the1.75Vrms input
...
where is the 26db of voltage gain at the output?

the A7 spec is gain is 26/29db for the 1.75Vrms input
...
where is the 29db of voltage gain at the output?

There's just one explanation: 3e Audio provide the input sensitivity for the low gain switch position only. Think about it, input sensitivity and max. power output simply cannot stay the same if the gain is increased, because they depend on each other. Also, max. power cannot be increased with higher gain upfront, as it is limited by other factors. => In the high gain setting, input sensitivity must higher (lower voltage):
Vin = Vout/A
Pout = (Vout)²/R
Vin = sqrt(Pout * R)/A

... with A being the voltage gain. Higher gain means that the required input voltage to get Poutmax decreases (valid for all values of R, as long as the amp can handle.the load).

is it coincidence that the rear se input gain switch is listed as 25 and 28.5 for both amps on page 4 (although the picture above that spec is the A5, the manual is for both units so that could be the spec for the A7 switch , this is somewhat vague)
Or is it possible that the 23/26db gain spec is for the A5 (and the 26/29db for the A7) rear SE gain switch as I maintain?

The actual silk screen on the A5 retail units is L and H for the gain switch. No exact numbers are given. The manual is probably just wrong.

I read the specs like RCA gain L(ow) means 23 dB for all A5 models and 26 dB for all A7 models. Consequently, H(igh) means 26 dB for the A5 and 29 dB for the A7.

I think it makes sense, at least.

 

[jlx]

I read the specs like RCA gain L(ow) means 23 dB for all A5 models and 26 dB for all A7 models. Consequently, H(igh) means 26 dB for the A5 and 29 dB for the A7.

That was my entire point all along:
that the 23/26db specification given for the A5 was for the input buffer gain and it was not the overall amp's gain spec. It seems you now sort of may agree with this, since the amp can not do 26db of gain (nor can the A7 can do 29db of gain)
He cited that spec as proof of the amps supposed 3db additional output, which of course technically it does not have., so he claimed that this spec was the amp's gain.
I claim it is not the amp's gain spec, it is the input buffer gain spec, something entirely different from this or any other amps output gain
It was never about 2.2 vs 3 per say, I cited my numbers as proof.
As such the amp stage is responsible for the additional 2.2-2.4db, or whatever it may be even if it was 3db. It's not the input buffer making the A5's additional 100W at 1% THD+N into a 4 ohm load.
Logically it seems you have also come to my original conclusion that the A5 23/26db spec referenced here is for the input buffer gain via the switch.
I may be a lousy engineer but little technicalities such as this do matter to me.

There's just one explanation:

There is another simpler explanation:
That the 23/26db gain listed under the single ended input column are the input buffer gains (via switching) as per the normal conventions used by most amp manufacturers . Not the amps overall gain.

After a few decades of reading amplifier white pages, mostly class D by preference, I find that the gains presented as they are here are for the input buffers when they are listed under single ended and/or balanced input columns as they are presented by3eAudio. The actual amps gain is always a single, invariable number irrelevant of single or balanced source.
They generally fall in the 26db range of gain for single ended and around 20db of buffer gain for balanced input (3.5Vrms sensitivity) irrelevant of how powerful the amp is. Occasionally there are lower gains for use with DACs or other gear with 7,10 or 12V balanced outputs.

the observed SPL for any given volume setting on the pre-amp does not depend on the maximum power output of each amp.

I am perplexed by this.
For any preamp signal, let's say an output of X volts, going into 2 amps of equal listed input sensitivity any output SPL difference is entirely dependent upon one of the power amps greater maximum output capability.
At line level input of X amp #1 that has 400w capability will output more power then the same X line level going into amp #2 that maxes out at 100w
Put another way that same signal X (lets say 1.25Vrms) that may call for a 50% output from both amps will get you 200w from amp #1 and 50w from amp #2. Does that additional wattage not give us greater SPL?
It really is starting to feel like this discussion is getting very repetitive so I'm out.

 

[harkpabst]

That suits me well, cause I don't have the time to discuss this with you either. But please, quote me correctly.
This:

With two power amplifiers, both driven within their operating limits, and everything else being equal, the observed SPL for any given volume setting on the pre-amp does not depend on the maximum power output of each amp.

Not this:

the observed SPL for any given volume setting on the pre-amp does not depend on the maximum power output of each amp.

"Everything else being equal" includes gain. Overall voltage gain. Output to input. The same overall voltage gain, which I proofed to be 23 dB for the A5 and 26 dB for the A7. The SPL depends on gain, not maximum power output. I really thought you got that.

If you switch the overall voltage gain from 23 dB to 26 dB (A5, 26 dB to 29 dB for the A7 respectively), then the input sensitivity changes.

These numbers are not buffer stage gain.

 

[jlx]

That suits me well, cause I don't have the time to discuss this with you either. But please, quote me correctly.
This:

Not this:

"Everything else being equal" includes gain. Overall voltage gain. Output to input. The same overall voltage gain, which I proofed to be 23 dB for the A5 and 26 dB for the A7. The SPL depends on gain, not maximum power output. I really thought you got that.

If you switch the overall voltage gain from 23 dB to 26 dB (A5, 26 dB to 29 dB for the A7 respectively), then the input sensitivity changes.

These numbers are not buffer stage gain.

So mates I think it is appropriate for me to say that I have royally screwed up and I am in error here. It is clear to me that I am in no condition to post at the moment as I am likely typing nonsense. After 5 days of heavy duty painkillers after a procedure, followed by extreme boredom, my mind is in a very foggy state. Trying to have any complex thoughts is an effort, it feels as if I am trying to swim in thick syrup.

But I am the idiot here, it's not the meds fault. I should have heeded the warning signs:
1 I asked myself what 1 +1 equals, the answer was apple, I think I'd like to eat an apple
2 typing 3 sentences takes 15 minutes, and the sentences needed several further rewrites...
this is not good

I ask for everyone's forgiveness for wasting their time with whatever stupidity I may have posted here. I'm quite embarrassed and I intend to delete my postings of the last few days when I am able to read them in a more lucid state. That day is not today as I'm on a lower drug dosage but thinking is still difficult.

I am not afraid to make a fool of myself on occasion, to call myself an idiot and have a good laugh about it later. However, I am very disturbed that I may have caused confusion for the fellows here that are less technical. That is just not cool.

This has taken my drug addled mind 30 minutes to type up and I'm exhausted trying to make sense. I am slightly less wonky than yesterday but I am certainly not all here.

In summary:
I'm an idiot
I humbly ask for your kind understanding and I appreciate your tolerance
Powerful painkillers and I do not get along very well, I'm uncomfortable, irritable, itchy, and a borderline moron right now
I need to stop typing

Apologies to all and my thanks to those that have put up with me
J

 

[harkpabst]

I humbly ask for your kind understanding and I appreciate your tolerance
Powerful painkillers and I do not get along very well, I'm uncomfortable, irritable, itchy, and a borderline moron right now

No need to be too hard to yourself. Questioning what others say can be really helpful, even if it doesn't change the result in the end. It forces others to rethink their own point of view and make sure their thoughts are valid.

Even more importantly, you really have to do whatever helps to get well. Keep quiet when you feel like it, speak out loud and twist your brain around other problems if you are sick of your sickness. We can surely stand that.

Take care.

 

[gaston312]

we had made some change base on user feedback and suggestion from ASR member, thanks again for all of your advice and help us keep improve.

• Auto power off time set to 20 mins
• Increase audio detection sensitivity RCA: 200uVrms; XLR: 400uVrms,this significantly meet some user listening in very very low volume.
• Auto audio sensing power on/off can be disable/enable by user.

This may seem like a stupid question: the red light means that the amp is on? Because I tried to power it off manually, but 2 seconds later the click and the red light comes back on automatically. The wiim ultra is turned off when I do this.
Also, I tried to enable/disable auto sense with these instructions but there’s no flashing of rca and xlr leds… hours go by and the red light is always on. Is this how it works?

 

[stigger]

No, for me it works exactly as described in the quoted post. Try disconnecting the wiim and see if the amp turns off after 20 minutes?

 

[gaston312]

No, for me it works exactly as described in the quoted post. Try disconnecting the wiim and see if the amp turns off after 20 minutes?

Tried that, one hour later it’s still on…

 

[gaston312]

only way to turn it off is to unplug it. This makes a small pop sound, and at the same time all 4 led lights flash once.

 

[harkpabst]

Also, I tried to enable/disable auto sense with these instructions but there’s no flashing of rca and xlr leds…

Did you make sure to push the button for 5 full seconds?

Because I tried to power it off manually, but 2 seconds later the click and the red light comes back on automatically.

Does this mean the amp does switch off (relais is clicking, all LEDs off) but it switches on after two more seconds with no input signal?

 

[gaston312]

Did you make sure to push the button for 5 full seconds?


Does this mean the amp does switch off (relais is clicking, all LEDs off) but it switches on after two more seconds with no input signal?

Even more than 5 seconds, and nothing . It just turns off and then turns back on automatically.

And yes, it means what you just said

 

[yavormoskov]

I decided to order this amplifier but there is something stopping me. Nobody can tell me how much import duties/tariffs I am going to have to pay for it in the USA. On Friday I tried to figure it out to no avail. 3e audio did not respond. The local tariffs office at the port of entry told me they have no idea which is ridiculous. They are the local government clerks in charge of collecting tariffs, it's very absurd they don't know. And DHL here in Atlanta also told me everything has changed and they don't accept consumer electronics packages from China to USA for the moment?! I am not sure what to do. Is there any local US based distributor you heard of? Thanks.

 

[olieb]

And DHL here in Atlanta also told me everything has changed and they don't accept consumer electronics packages from China to USA for the moment?!

Well, that settles it, doesn't it?
When the smoke has blown there maybe tariff of 34% (or whatever, who knows), but new smoke may come anytime and push everything of(f) course.
In EU we have Audiophonics as a vendor, but in the USA, I don't know.

 

[Alannn]

I decided to order this amplifier but there is something stopping me. Nobody can tell me how much import duties/tariffs I am going to have to pay for it in the USA. On Friday I tried to figure it out to no avail. 3e audio did not respond. The local tariffs office at the port of entry told me they have no idea which is ridiculous. They are the local government clerks in charge of collecting tariffs, it's very absurd they don't know. And DHL here in Atlanta also told me everything has changed and they don't accept consumer electronics packages from China to USA for the moment?! I am not sure what to do. Is there any local US based distributor you heard of? Thanks.

The "De Minimis provision" for goods from China and Hong Kong ends May 2. So, until May 2, as long as each individual package is worth $800 or less, they aren't required to pay import fees or go through typical customs inspections.

 

[jlx]

Well, that settles it, doesn't it?
When the smoke has blown there maybe tariff of 34% (or whatever, who knows), but new smoke may come anytime and push everything of(f) course.
In EU we have Audiophonics as a vendor, but in the USA, I don't know.

sort of, kind of, maybe or maybe not

I've spoken to a close friend (and have seen communications from 2 other small companies) in the speaker manufacturing sector that rely on China imports for a large part of their BOM.
As best they can guesstimate (they are not very clear at the moment):
the old tariff was something like 6.5 or 7.5% (I don't recall this number exactly, so bear with me)
Feb added 20%
April added 34% for an EXPECTED TOTAL tariff of 61.5% (or 60.5%) VS the 7.5% (or was it 6.5%?) ) paid in January 2025.
This is an increase of 54% for all declared values. Note that these new tariffs did not replace the previous ones, they are all additive (this is their current understanding as I have been told).
So If in January a speaker costs a company $1K and the customs declaration reflects this price, as it should, the new cost is $1540 with the new tax in place (tariff or whatever you want to call it). If they had sold this speaker for $2K before Feb of this year, that will certainly change BIG TIME.

If they get parts from the EU I think that tariff increases by 20%, it is possible that the rate is now 20% total but I think it may be 20% added to the existing rate. Other countries tariffs are anywhere from 10% to over 54% added to the old tariffs paid previously. Here again there is confusion as to if the new numbers are added to or if they directly replace the old tax rate paid at the US border. As an example, German auto imports were tariffed at 2.5% before all of this started, soon to be 22.5% (or is it 20% total?)
But wait for it, I have also read that the additional 20% is for everything EXCEPT autos, that they will be taxed at 25% (total? additive?)
It is a confusing mess out there at the moment. You would be right to ask if I'm still loaded on pain killers after reading this, but I am not.

IT IS SO CONFUSING!!!!

What directly applies to us in the USA in general and in this forum specifically, is that the "de minimis" exemption for imports of under $800 to individuals is GONE very soon. As such we should all get hit with either 54% or is it 61.5%?? (so an additive tax) for these 3EAudio amps in May. It is not very clear right now and confusion is rampant. Smaller companies are especially nervous.