agedhorse

Maybe they discovered an error and revised the docs and chassis? Happens sometimes in spite of best efforts. The 900 watt models are 2 ohm capable and use a switch to operate at 2 ohms.

Not according to the docs on the Darkglass website: https://www.darkglass.com/app/uploads/2022/05/AO500-Manual.pdf Maybe you are looking at the wrong model, or there is an error in your documentation? 3 ohms minimum, which is 4 ohms nominal with room for excursions into sub-nominal territory. I am very familiar with the module they use and the following is accurate.

According to the docs, it’s 4 ohms minimum load. I wonder if this is the root cause?

Is there a switch that needs to select 2 ohm operation?

As a reminder, this is similar enough symptoms of an intermittent SpeakOn plug. I have seen intermittent plugs for two main reasons: 1. Counterfeit or knock-off, non-Neutrik branded plugs (major issue, and a cause of a fair amount of warrant claims unrelated to the amp) 2. Improperly assembled SpeakOn plugs where the assembler trimmed the wire, which then cold flowed under the pressure of the binding screw and loosened. Both of these are well known issues that I deal with way too often in customer support.

Any amp designed to IEC-60965 or 62368 in the EU must operate (and is tested by a nationally recognized test lab) at 230V +/-10%. That would be 253V high line and 207V low line. If the amp needs certification to operate in regions with nominal 240V, this would include Australia and New Zealand), the national differences approvals would add a 264V high line test. Virtually everything of any quality these days is designed to operate at a high line of 264V because it makes no sense to design multiple versions (at least with SMPS) because it would add more cost to the certification process than could be justified. The homogenization limits tolerances really do work quite well in practice, and in fact utilities have adjusted their generating and distribution voltages a few percent to improve compliance as well. Australia has some additional challenges, primarily around voltage regulation on long transmission and distribution lines with varying loads in the Outback.

That’s unfortunate.

Most repairs include a warranty on the repair. Did you follow up with them on this?

I posted before hearing the news...

If not in the UK, Italy isn't THAT far from the UK (though admittedly farther appearing since BREXIT)

Contact MarkBass and see what service options they have for you.

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.

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.

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".

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.

Tastes in speakers and speaker voicing certainly have changed. What we) as designers) can do with Neo drivers is something we had been wishing for decades ago. This is a better example of player’s constantly asking for something that designers were unable to deliver until the new technology came about.

Not IME, provided you have access to a QUALIFIED technician who knows how to CORRECTLY diagnose problems. In quality amps, failures of the power amp and class D sections are really quite rare. Most failures are related to exactly the same issues faced by older school amps, though overall the newer amps are better designed and built, with better quality parts. When there is a power supply or power amp failure, generally it's less expensive to replace the power module in a class D amp than it is to repair a class AB/G/H amp of similar power rating. Many older amps are not economically repairable with such failures because the cost of repair exceeds the value of the amp... ie. you can buy a used amp for less than it would cost to repair the bad one. With cheaper amps (say <$300), unless the shop is very good and accurate with diagnosis, it may not be worth repairing regardless of the type of amp. This is the nature of a highly efficient manufacturing environment. This is not an are where I have extensive experience, this mentality is at odds with the companies I have worked for throughout my career.

Actually, how an amp sounds when it's driven hard is not so much the type of power supply and power amp, but the intent of the designer and the choices made in voicing and dynamics of the circuitry. Music has evolved, so have the designs at the same time. If the voicing and dynamics response of an older school amp or voicing choices appeal more to you, then that's what you should play, and quit disparaging those who don't share your personal preferences and tastes.

This is not true, and most (not all) amp manufacturers no longer make class AB amps anyway, so why would they say this? IME, those who do not offer class D amps are the ones who have struggled with, or stumbled badly with class D technology. Those who haven't stumbled have not looked back and continue to move forward. This is not true of Mesa, certainly since 2014 when they "discovered" how much better and more reliable class D is. In most cases, they don't. Many switchmode power supplies are MUCH beefier than their heavy line frequency supplies, especially at 230V/50Hz. A quick test of SMPS output impedance shows how obvious this is too. Why can't those folks who live and die by the heavy gear as a preference refuse to acknowledge that other players might have different preferences and tastes that are just as valid? I've designed gear in both camps, each amp model does exactly what I intended with regards to performance and voicing with ZERO regard for the amp's size, weight or technology used.

Made in Italy or Indonesia?

Things are improving somewhat, but we are still backlogged by months. I’m still frustrated, that’s not improving

Can’t fix stupid…or lazy!

If the copper is damaged like this, there is something very wrong with the cable.

The proper footswitch won't damage your amp either!

The difference in maximum volume between the D-800 and D-350 is just about 3dB It's not a practice amp, it's a totally giggable amp with the features of the D-800, but with the bright switch replacing the deep switch, less power, convection cooling (no fan), smaller, lighter and with a USB power port. The D-350 doesn't support 2 ohms. An amp this low powered wouldn't be the ideal choice for driving the typical cabinet combinations that would make up a 2 ohm load, these players would be better served by the D-800 anyway.