Topping Mini 300 Amplifier Review

[OldTimer]

Yes, I would even pause for ten minutes and then rewind to listen to the same track again. You only need to repeatedly listen to a few tracks you are familiar with to spot the issue. I have thousands of songs in my PC music library and regularly listen to a specific set of familiar tracks every day.

Based on my observations over the past six months, the sound quality starts to change most of the time after playing a few songs, or at most within an hour. The difference is something you can absolutely hear. It usually degrades, but sometimes it can also get better. The sound fluctuates across the entire frequency range, especially the drum hits; it is very easy to notice on tracks with low frequencies.

I can hear a few distinct levels of sound quality, and the amp randomly toggles between them. To this day, I still don't know the true potential of this amp, or which level represents its actual performance.

Please forgive my somewhat vague description, but this is honestly so bizarre. I know this is not a placebo effect.

Just be honest and you are good to go.

 

[oldloder]

I haven't measured it yet. It happens every day. I sit in front of my computer daily, and my listening position is fixed.

I've basically ruled out all other factors; the only thing left to try is changing the speakers. For reference, my current speakers are the JBL Stage A130.

You've ruled out your source and cables? Perhaps a Class AB amp on hand? Have you tried playing test tones rather than music?

 

[tb2025]

You've ruled out your source and cables? Perhaps a Class AB amp on hand? Have you tried playing test tones rather than music?

Yes, but the problem still exists. I have a TDA7294 amplifier, and I haven't found this kind of problem.

 

[whazzup]

Yes, I would even pause for ten minutes and then rewind to listen to the same track again. You only need to repeatedly listen to a few tracks you are familiar with to spot the issue. I have thousands of songs in my PC music library and regularly listen to a specific set of familiar tracks every day.

Based on my observations over the past six months, the sound quality starts to change most of the time after playing a few songs, or at most within an hour. The difference is something you can absolutely hear. It usually degrades, but sometimes it can also get better. The sound fluctuates across the entire frequency range, especially the drum hits; it is very easy to notice on tracks with low frequencies.

I can hear a few distinct levels of sound quality, and the amp randomly toggles between them. To this day, I still don't know the true potential of this amp, or which level represents its actual performance.

Please forgive my somewhat vague description, but this is honestly so bizarre. I know this is not a placebo effect.

My suggestion: When you start encountering the issue again, try to capture the audio from your speaker, probably easiest is stick your mobile phone right in the center of the A130 woofer. Then separately, when the issue is gone, or if you can get the amp to go back to its 'original normal state', then do a recording again, so that everyone here can compare. Ideally not any random track. Try running a test tone like the one I linked to below. I used 50hz mainly because you mentioned the problem is at lower frequencies plus it should still be audible through the A130. Or use 60hz. You can also play the test tone below for an hour and see if there're any detectable changes.

Finally, Amir did mentioned some problems when testing his unit, may or may not be related:

It was difficult to measure power at 40 Hz as the amp would go into some intermediate protection mode where it would distort but not shut down. Eventually I got a single measurement:

 

[tb2025]

My suggestion: When you start encountering the issue again, try to capture the audio from your speaker, probably easiest is stick your mobile phone right in the center of the A130 woofer. Then separately, when the issue is gone, or if you can get the amp to go back to its 'original normal state', then do a recording again, so that everyone here can compare. Ideally not any random track. Try running a test tone like the one I linked to below. I used 50hz mainly because you mentioned the problem is at lower frequencies plus it should still be audible through the A130. Or use 60hz. You can also play the test tone below for an hour and see if there're any detectable changes.

Finally, Amir did mentioned some problems when testing his unit, may or may not be related:

Thanks! I'll give it a try.

 

[tb2025]

To close the loop (for no one) for my earlier post about the temperature of components in the mini 300:

Topping Mini 300 Amplifier Review

Sorry, that doesn't make sense. You're overlooking why Topping chose this cooling design and why it is so optimal, especially for this specific amplifier. Of course, it is incredibly easy and cheap to implement cooling based on direct convection using a finned heatsink. However, the "more is...

www.audiosciencereview.com

Texas Instruments does rate the TPA3255 up to 70°C operating range. I'm not refuting all the other comments about everything being in spec.
Just that in my case, I have it on easily more than 12 hours almost daily until I shut down for the day, and it's at my desktop pc with its own fans (so 1 more fan isn't too noticeable). And as have been mentioned already, decreasing the operating temperature of electrical and electronic components by 10°C typically doubles their expected lifespan and reliability, so if it doesn't cost me much to run the amp at lower temps, why not?

To get an estimate of the heatsink temp in the chassis, I let the amp stay powered in the chassis and go about my business for some time, then powered off and pull out the board to check the temp. I got 57°C (note that it had cooled about 2 degrees by the time I finished fiddling around with the camera and the room sensor, about a minute later). Chassis temp was 41°C.
View attachment 545884


Then I added an cheap external usb fan (supposed to be 18db) that came with its own rubber feet, because that's the easiest way I could think of to add some active cooling. And added some silicon feet under the amp as well to allow some airflow between amp and fan.
View attachment 545887


Let the amp run again in the chassis with the external fan beneath, then powered off, pulled out the board and checked the temp again. With some airflow, the heatsink temp dropped to 46°C (again, a short pause before I could take the photo). Chassis temp was at 32°C.
View attachment 545892


To summarize what I could measure (with room temp at 29-30°C, 84-86°F):

Heatsink temp in chassis: 57°C / 134°F
Heatsink temp in chassis with external bottom fan: 46°C / 115°F
Heatsink temp in the open: 50°C / 122°F
Heatsink temp in open with fan (pointed at heatsink): 34°C / 93°F


Yes, there's likely going to be greater dust buildup over time. And 18db fan noise (in my case). Pros and cons. Please use the data and make your own decisions.

I found that heat affects its sound performance. Every time I try to turn off the fan and wait fifteen minutes for heat to build up in the chassis before playing, the sound quality degrades. It's as if it loses its resolution, resulting in high-frequency degradation, which should be caused by a certain type of distortion, making me just want to turn off the music. Then, when I turn the fan back on until the chassis is no longer hot, the sound quality comes right back. I’ve verified this several times, which proves it is highly sensitive to temperature.

 

[Angst92]

I found that heat affects its sound performance. Every time I try to turn off the fan and wait fifteen minutes for heat to build up in the chassis before playing, the sound quality degrades. It's as if it loses its resolution, resulting in high-frequency degradation, which should be caused by a certain type of distortion, making me just want to turn off the music. Then, when I turn the fan back on until the chassis is no longer hot, the sound quality comes right back. I’ve verified this several times, which proves it is highly sensitive to temperature.

Might need to get proper measurements of the output to confirm that's not just placebo.

 

[tb2025]

Might need to get proper measurements of the output to confirm that's not just placebo.

I don't have measuring gear, but I've consistently noticed this behavior. Curious if anyone else has observed or measured the same on their amp?

 

[Tell]

I don't have measuring gear, but I've consistently noticed this behavior. Curious if anyone else has observed or measured the same on their amp?

You have a mic on your phone, so download some random app that can show peak spectrum over time, Spectroid for Android for example, play some pink noise for a few seconds and save the graph by screenshotting it or whatever. Now do that both when it's cold and when it's warm and post them here if they differ.

 

[whazzup]

I don't have measuring gear, but I've consistently noticed this behavior. Curious if anyone else has observed or measured the same on their amp?

i didn't really notice distorted audio, though maybe I wasn't listening for it. Maybe you can single out some youtube videos at specific times that should clearly exhibit the distortion? As the rest have also suggested, if it's clearly audible to the human ear, the phone mic should be able to pick it up.

 

[gasolin75]

Atleast double in 4 ohm compared to 8 ohm and no pop noise when turning it on/off + stabel on power up nice

 

[addeps2]

Atleast double in 4 ohm compared to 8 ohm

Distortion doesnt count, bro.
Its circa 90W at 4 ohm before the distortion shoots up.

So its more like 1.8 times the power at 4 ohm (from 8 ohm).

 

[gasolin75]

OH

 

[fwwwk]

anyone tested 2 ohms drive preferably with some capacitive/ inductive load? or similar TPA 3251 in BTL mode

thank you

 

[gasolin75]

Consider a preamp-plus-dac with a 12 volt trigger output to power the Topping Mini 300 up or down.

How much are you comfortable spending ?

A wiim streamer

 

[Jarrett]

Atleast double in 4 ohm compared to 8 ohm and no pop noise when turning it on/off + stabel on power up nice

Surprised there aren't more reviews going around 7 months later.

 

[gasolin75]

There are so many other amps, people might not take notice of a inexpensive 139 euros amp

 

[somebodyelse]

anyone tested 2 ohms drive preferably with some capacitive/ inductive load? or similar TPA 3251 in BTL mode

thank you

The TPA3251 datasheet recommends 2.7 ohms as the minimum load impedance for BTL mode. Power will be limited by the current capability - you'll hit overcurrent protection before voltage clipping. If you need to drive 2 ohms you should look for an amp that's designed for it, like a TPA325x in PBTL mode. The 3e A5 for example.

 

[gasolin75]

I myself have just swapped the Mini 300 out for a pair of B200s for this very reason. At low listening levels, I’d be lying if I said I could pick one out from the other blindly, but once cranked up, the Mini 300s can’t push dynamic swings the way the beastly B200s can.

You compared a 139 euros amp to 2x600 euros (1200 total) mono amps with minimum 2x 200watt in 8 ohm vs just under 2x100 watt for the Topping MIni 300

What compare fuel econmy between a truck and a car ?

 

[addeps2]

Id just like to add to the knowledge base that according to Topping the Mini 300 has the following total impedance (for anyone hoping to use it from their non-Topping preamp-output):

"Mini 300: Balanced XLR 5KΩ, Single-ended RCA 1KΩ" (provided via email, from TOPPING service)