Beware cheap Chinese amps!

[prowla]

I found a great 4-channel 1U 4x1300 Watt power amp on ebay. 
It took a couple of weeks to arrive and I had to pay duty on it. 
I got around to connecting it up this evening. 
Plugged it in, pop!, house power tripped, slight electrical smell. 
Grrr, now I’ve got to chase up the issue with the seller. 
A load of hassle and presumably I’ll lose money on the inevitable return. 
 

[Bill Fitzmaurice]

4x1300 watt should have tipped you off. Yes, such amps exist, but only from the likes of Powersoft, and only for mucho dinero.

[stewblack]

1 hour ago, prowla said:

I found a great 4-channel 1U 4x1300 Watt power amp on ebay. 
It took a couple of weeks to arrive and I had to pay duty on it. 
I got around to connecting it up this evening. 
Plugged it in, pop!, house power tripped, slight electrical smell. 
Grrr, now I’ve got to chase up the issue with the seller. 
A load of hassle and presumably I’ll lose money on the inevitable return. 
 

Always think these things are worth a punt. The occasions they work out leave me very smug.

When they don't on the other hand...

My sympathies.

[Downunderwonder]

Did you RTFM before plugging it in? Some amps have internal manual switching to enable 240V.

[prowla]

1 hour ago, Downunderwonder said:

Did you RTFM before plugging it in? Some amps have internal manual switching to enable 240V.

It's labelled 220V and supplied with only a UK power cable.

[leroydiamond]

16 hours ago, prowla said:

It's labelled 220V and supplied with only a UK power cable.

AC voltage in the UK IS RATED AT 240V and has been measured up to 250V. 220V is standard Voltage in EU, so that might be an issue. 

[agedhorse]

2 hours ago, leroydiamond said:

AC voltage in the UK IS RATED AT 240V and has been measured up to 250V. 220V is standard Voltage in EU, so that might be an issue. 

Actually, the standard voltage in Europe is now nominal 230V, the UK began the harmonizing to nominal 230V about 25-30 years ago. Initially, part of this harmonization included a change (lowering) of the maximum voltage to +5% so 240V x 1.05 = 252V which is close enough to the EU's 230V x 1.1 = 253V for high line limits. Slowly the nominal 240V has drifted down, combined in part with a tightening of the low line tolerance (now +10%/-6%) which brings it within the standard EU limits.

[agedhorse]

On 02/07/2022 at 14:17, prowla said:

I found a great 4-channel 1U 4x1300 Watt power amp on ebay. 
It took a couple of weeks to arrive and I had to pay duty on it. 
I got around to connecting it up this evening. 
Plugged it in, pop!, house power tripped, slight electrical smell. 
Grrr, now I’ve got to chase up the issue with the seller. 
A load of hassle and presumably I’ll lose money on the inevitable return. 
 

IIRC, some of us tried to warn you (didn't we?) 

 

We have a saying here... when you choose to sleep with snakes, it's likely that you will get bitten. It goes hand in hand with "buy once, cry once".

[JottoSW1]

49 minutes ago, agedhorse said:

IIRC, some of us tried to warn you (didn't we?) 

 

We have a saying here... when you choose to sleep with snakes, it's likely that you will get bitten. It goes hand in hand with "buy once, cry once".

What you can see for sale on't-net.

Facebook snake dude Chandler being silly with 14 foot King Cobra's in his "Serpentarium' or dodgy sweatshop power amps 🙀

[prowla]

7 hours ago, agedhorse said:

IIRC, some of us tried to warn you (didn't we?) 

 

We have a saying here... when you choose to sleep with snakes, it's likely that you will get bitten. It goes hand in hand with "buy once, cry once".

I don't recall you trying to warn me?

eg. in

or

or (though you had posted a comment in this one before I joined the thread).

 

[Woodinblack]

On 02/07/2022 at 22:17, prowla said:

Plugged it in, pop!, house power tripped, slight electrical smell. 
Grrr, now I’ve got to chase up the issue with the seller. 
A load of hassle and presumably I’ll lose money on the inevitable return. 

 

If it was defective like that, you shouldn't lose money on the return.

[prowla]

26 minutes ago, Woodinblack said:

 

If it was defective like that, you shouldn't lose money on the return.

Fingers crossed - I'll see what the response is.

There's also the question of VAT & duties.

[Chienmortbb]

As some of you know I have used and evaluated many class D modules over the years and some of them included mains Switch Mode Power Supplies. One in particular, from a long established Chinese company would work intermittently but most of the time it would go into the protect mode.  I had contacted some buyers of this amp in Europe to check that they were happy and to get their opinions on the amp. In all cases they gave a glowing report.

 

I contacted the company and re-read the specs and noticed that the upper limit for main voltage was 240V. As @agedhorsementioned a few posts earlier, we used to have a nominal mains voltage of 240V before joining the EU but sensibly WE persuaded the EU that mains voltages should be harmonised. It was of course a compromise but it did remove those two pesky 220/240V taps on amplifiers, reducing costs.

 

As an aged dog myself, I grew up with 240V and sort of assumed that the particular amp would work in the UK. I contacted the company and they were very helpful. As a retired Electronic Engineer, I still have much of my equipment (boasting again) and  I was able to talk to them on a technical level and we soon sorted the problem out. The point here is that there are some good Chinese companies, but many either do not understand out local conditions or simply don't care as they are just resellers.

 

So the lesson is, understand and study the specs and buy from reputable sellers. There are Companies here in the UK, Europe and the USA that sell low cost amps and if they sell them, they are responsible for them. However the safe bet is to buy from reputable brand from a reputable seller.

 

 

[prowla]

3 hours ago, Chienmortbb said:

As some of you know I have used and evaluated many class D modules over the years and some of them included mains Switch Mode Power Supplies. One in particular, from a long established Chinese company would work intermittently but most of the time it would go into the protect mode.  I had contacted some buyers of this amp in Europe to check that they were happy and to get their opinions on the amp. In all cases they gave a glowing report.

 

I contacted the company and re-read the specs and noticed that the upper limit for main voltage was 240V. As @agedhorsementioned a few posts earlier, we used to have a nominal mains voltage of 240V before joining the EU but sensibly WE persuaded the EU that mains voltages should be harmonised. It was of course a compromise but it did remove those two pesky 220/240V taps on amplifiers, reducing costs.

 

As an aged dog myself, I grew up with 240V and sort of assumed that the particular amp would work in the UK. I contacted the company and they were very helpful. As a retired Electronic Engineer, I still have much of my equipment (boasting again) and  I was able to talk to them on a technical level and we soon sorted the problem out. The point here is that there are some good Chinese companies, but many either do not understand out local conditions or simply don't care as they are just resellers.

 

So the lesson is, understand and study the specs and buy from reputable sellers. There are Companies here in the UK, Europe and the USA that sell low cost amps and if they sell them, they are responsible for them. However the safe bet is to buy from reputable brand from a reputable seller.

Aye.

In my case, the amp was shipped to my address in the UK and supplied with a UK 13A plug mains lead.

It was sold with the following description: "Input Voltage: AC220~240V, 50/60Hz  /    AC110~120V, 50/60Hz ( 110V US Versions only have New Design Versions, please choice new design if you use it in USA)".

The case has a "Do not open" anti-tamper sticker over one of the lid screws.

The seller's rating is: easydo2012 (3742)

[agedhorse]

13 hours ago, Chienmortbb said:

As some of you know I have used and evaluated many class D modules over the years and some of them included mains Switch Mode Power Supplies. One in particular, from a long established Chinese company would work intermittently but most of the time it would go into the protect mode.  I had contacted some buyers of this amp in Europe to check that they were happy and to get their opinions on the amp. In all cases they gave a glowing report.

 

I contacted the company and re-read the specs and noticed that the upper limit for main voltage was 240V. As @agedhorsementioned a few posts earlier, we used to have a nominal mains voltage of 240V before joining the EU but sensibly WE persuaded the EU that mains voltages should be harmonised. It was of course a compromise but it did remove those two pesky 220/240V taps on amplifiers, reducing costs.

 

As an aged dog myself, I grew up with 240V and sort of assumed that the particular amp would work in the UK. I contacted the company and they were very helpful. As a retired Electronic Engineer, I still have much of my equipment (boasting again) and  I was able to talk to them on a technical level and we soon sorted the problem out. The point here is that there are some good Chinese companies, but many either do not understand out local conditions or simply don't care as they are just resellers.

 

So the lesson is, understand and study the specs and buy from reputable sellers. There are Companies here in the UK, Europe and the USA that sell low cost amps and if they sell them, they are responsible for them. However the safe bet is to buy from reputable brand from a reputable seller.

 

 

The harmonizing of the UK to 230V nominal European standards means that the high line limits are the same. 
 

For amps that truly comply with CE under the CB scheme, they are tested at the high line limits, it’s one of the required tests that the amp must pass.

 

Most of the “no name” amps available on the various websites do not carry valid CB safety or EMC certifications, and those that have the CE mark applied are often not eligible to carry that mark.

[agedhorse]

15 hours ago, prowla said:

I don't recall you trying to warn me?

eg. in this thread

The following post is from TalkBass, ahead of you post about looking at a cheap 1300W x 4 channel Chinese amp. Yes, the information was provided and discussed by other members in detail.

 

Some manufacturers understand the value that premium platforms like ICEPower bring to their customers. They also tend to follow safety and EMC rules, and avoid no-name amp solutions because they know the pitfalls in performance and reliability.

Some manufacturers also understand how to exploit unpublished attributes of the ICEPower platforms to go farther than the published specs might (inaccurately) indicate.

[prowla]

9 hours ago, agedhorse said:

The following post is from TalkBass, ahead of you post about looking at a cheap 1300W x 4 channel Chinese amp. Yes, the information was provided and discussed by other members in detail.

 

Some manufacturers understand the value that premium platforms like ICEPower bring to their customers. They also tend to follow safety and EMC rules, and avoid no-name amp solutions because they know the pitfalls in performance and reliability.

Some manufacturers also understand how to exploit unpublished attributes of the ICEPower platforms to go farther than the published specs might (inaccurately) indicate.

Ah - I do find TalkBass a bit difficult to follow.

[Phil Starr]

On 02/07/2022 at 22:17, prowla said:

I got around to connecting it up this evening. 
Plugged it in, pop!, house power tripped, slight electrical smell. 
Grrr, now I’ve got to chase up the issue with the seller. 

I think in one of the other threads you said you hadn't even turned it on? If so that suggests to me that the fault has to be before the mains switch on the amp and something is shorting before the power even reaches the amp. 

 

Obviously it's better to get your money back from the seller and you don't want to invalidate anything by opening her up but tripping the RCD with the amp switched off......

[prowla]

53 minutes ago, Phil Starr said:

I think in one of the other threads you said you hadn't even turned it on? If so that suggests to me that the fault has to be before the mains switch on the amp and something is shorting before the power even reaches the amp. 

 

Obviously it's better to get your money back from the seller and you don't want to invalidate anything by opening her up but tripping the RCD with the amp switched off......

Yes - it was just on plugging in the IEC cable, with the front switch of the amp off.

[BassmanPaul]

10 hours ago, prowla said:

Ah - I do find TalkBass a bit difficult to follow.

Me too! Especially after they banned me! LOL