Class D Amplifier options in India

adakadavuley

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I am thinking of getting rid of my Rotel RA 971. I am getting a hissing sound for 5-10 seconds on cold start up. Because of this I tend to keep the amp switched on instead of turning it on every time. I have a suspicion that our increase in electricity bills could also be because of this. We don't have an A/C or other heavy electrical equipment running. The amp is warm to touch even if it is kept idle. I guess the hissing is because of a capacitor issue.

This whole experience is making me look at Class D amps more seriously. The compact size and ability to go into stand by mode on idle is appealing. I read a few threads here about how they are competing with class A and AB amps nowadays. But it is tough to find options in India. Especially with AliExpress not working any more. I am ideally looking for something below 20K INR. Can stretch a bit more maybe. The popular ones with good measurements are not available in India I guess.

Mine is a sealed speaker with a sensitivity of 86db and impedance of 8 ohms. I already have a PC with Roon + Topping E30 for streaming and DAC. So I don't really need features like bluetooth. I just need a class D power amplifier with a volume knob and RCA inputs. Though features like sub woofer output and HDMI/Optical In would be nice if I want to connect a TV in the future.

Can you please suggest good class D amps which can power my speakers and are readily available for purchase in India?

I looked at the Yamaha WXA-50 which is available with only one online provider now. But it is slightly out of my budget at 40k. But I really like the form factor and Amir of ASR has given it a good review. I also really like the looks and build of Teac AI-101DA-B but it has only 26w @ 4 ohms and also has only an optical in so I cannot use my DAC.

On a tangential note, does anyone have experience ordering via desert cart/ubuy.co.in? Is it recommended? They constantly keep showing up in results when I search for products but I ignore them.

Thanks!
 

IndianEars

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Several current models of NAD integrated amps incorporate Digital Power Amps. They are available in India.

I would recommend that you buy a Digital amp only after a Home Demo / Trial.

It is not infrequent that Digital amp users complain they lack Grunt and slam,.. when driving some speakers, even though they have a Higher power power rating, and impeccable distortion specs. I know 2 dissatisfied friends. One of them sold his new amp soo after purchase....
 

catalyst360

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Topping PA3 available on headphone zone, SMSL SA300 (Shenzhen audio)

Another option is to look into Crown amps. At 86db spl your speakers aren’t particularly sensitive and wouldn’t mind some extra oomph. The xls1002 can be had for around 20k. You can use the E30 in pre amp mode and control the volume using its remote.

The Crown also provides DSP control over the signal so you could add a HPF to the speaker out should you need to integrate a sub in the future.
 
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reubensm

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I am thinking of getting rid of my Rotel RA 971. I am getting a hissing sound for 5-10 seconds on cold start up. Because of this I tend to keep the amp switched on instead of turning it on every time. I have a suspicion that our increase in electricity bills could also be because of this. We don't have an A/C or other heavy electrical equipment running. The amp is warm to touch even if it is kept idle. I guess the hissing is because of a capacitor issue.
hissing on cold start - one channel or both channels?
does the hissing appear for warm starts as well?
 

adakadavuley

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I have an Allo Volt D+ amp with attenuator which sounds very good. Ypu take a look. This is available in India and use with Allo recommended LPSU.
Thank you. Will checkout out the Allo Volt+ D more closely. I got turned away by the fact that it requires a external power supply.

I would recommend that you buy a Digital amp only after a Home Demo / Trial.

It is not infrequent that Digital amp users complain they lack Grunt and slam,.. when driving some speakers, even though they have a Higher power power rating, and impeccable distortion specs. I know 2 dissatisfied friends. One of them sold his new amp soo after purchase....
Not sure if I will be able to get a home demo now. But will keep this in mind. Thanks!

Topping PA3 available on headphone zone, SMSL SA300 (Shenzhen audio)
Thank you. Was not aware of Topping PA3. Also did not know shenzen audio delivered to India. Will check their site. Amit of Audio science review has not given a favourable rating to the PA3 but looks like Topping might have an updated line of speaker amps. Maybe I should wait.

hissing on cold start - one channel or both channels?
does the hissing appear for warm starts as well?
Happens in both channels. Does not happen if I shut it down for 3-5 mins and immediately start again. The duration of hissing varies depending on how long the amp has been switched off. It lasts only a few seconds if I turn it on after 15-20 mins.
 

ssf

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I have two Crown XLS2502's and use it for both HT and Stereo. Happy with it.
HT with the Marantz 7010 and Stereo with Tidal -> Roon on desktop PC to iFi Zen Dac -> FX Audio Tube Pre -> Crown XLS 2502.

ASR has done measurements of the Crown. You could probably look it up.
 
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reubensm

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Happens in both channels. Does not happen if I shut it down for 3-5 mins and immediately start again. The duration of hissing varies depending on how long the amp has been switched off. It lasts only a few seconds if I turn it on after 15-20 mins.
Got it, so essentially you have the hiss on both channels, from a cold or partially cold start.

There can be many reasons, if it was on 1 channel only, the common culprits would have been failing coupling caps, failing semiconductors, dry solder joints or microscopic cracks in PCB strips.

For both channels to have the same problem, the root cause has to be somewhere in the amp, where resources are shared between both channels. Not sure about the design features of your amp but generally, the common resources shared are the PSU, protection circuitry, input selector, sectional filter capacitors, shared OP Amps between channels, multiple-pole switches/dual POTs (they are technically separated electrically but are in close proximity), the PCBs themselves and the amplifier chassis. They key to fixing this issue is to be able to isolate the problem. If its an integrated amp, the first step would be to check whether the root case is with the Power or Preamp stages and go from there. In extremely rare cases, the amp may be also picking up some RF interference or electrical interference which is filtered when the amp warms up but this is highly unlikely. It is highly unlikely that coupling caps from individual channels will fail together (unless it is a magical coincidence).

One common characteristic that accompanies this problem is slight channel imbalance, but not always. An amp tech will always prefer to fix a dead amp as these require mostly mainstream diagnosis for obvious issues. If the amp plays normally with these exceptional traits, an experienced tech will require to go stage by stage.

My apologies as this is a bit off topic, with reference to the context of this thread but thought I'll share a perspective, just in case you decide to get the amp repaired. This is good info to know.
 

adakadavuley

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Got it, so essentially you have the hiss on both channels, from a cold or partially cold start.

There can be many reasons, if it was on 1 channel only, the common culprits would have been failing coupling caps, failing semiconductors, dry solder joints or microscopic cracks in PCB strips.

For both channels to have the same problem, the root cause has to be somewhere in the amp, where resources are shared between both channels. Not sure about the design features of your amp but generally, the common resources shared are the PSU, protection circuitry, input selector, sectional filter capacitors, shared OP Amps between channels, multiple-pole switches/dual POTs (they are technically separated electrically but are in close proximity), the PCBs themselves and the amplifier chassis. They key to fixing this issue is to be able to isolate the problem. If its an integrated amp, the first step would be to check whether the root case is with the Power or Preamp stages and go from there. In extremely rare cases, the amp may be also picking up some RF interference or electrical interference which is filtered when the amp warms up but this is highly unlikely. It is highly unlikely that coupling caps from individual channels will fail together (unless it is a magical coincidence).

One common characteristic that accompanies this problem is slight channel imbalance, but not always. An amp tech will always prefer to fix a dead amp as these require mostly mainstream diagnosis for obvious issues. If the amp plays normally with these exceptional traits, an experienced tech will require to go stage by stage.

My apologies as this is a bit off topic, with reference to the context of this thread but thought I'll share a perspective, just in case you decide to get the amp repaired. This is good info to know.
Thank you for the detailed reply. This is very helpful! I definitely want to get this fixed regardless of whether I get a new amp. Do you by any chance happen to know any good technician in Pune? I am new to this place so I don't know where to take it.

EDIT: I also forgot to mention that even the above is happening only after I connected a v guard stabilizer. Without the stabilizer, the hissing wouldn't stop and it would keep on increasing in intensity.
 

adakadavuley

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I have two Crown XLS2502's and use it for both HT and Stereo. Happy with it.
HT with the Marantz 7010 and Stereo with Tidal -> Roon on desktop PC to iFi Zen Dac -> FX Audio Tube Pre -> Crown XLS 2502.

ASR has done measurements of the Crown. You could probably look it up.
Sure will check it out. I guess it more suited when lot of power is required for HT/Subwoofer etc. Might be little over kill for me.
 

adakadavuley

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Thank you for the detailed reply. This is very helpful! I definitely want to get this fixed regardless of whether I get a new amp. Do you by any chance happen to know any good technician in Pune? I am new to this place so I don't know where to take it.

EDIT: I also forgot to mention that even the above is happening only after I connected a v guard stabilizer. Without the stabilizer, the hissing wouldn't stop and it would keep on increasing in intensity.
This is the stabilizer I use https://www.vguard.in/product-details/digi-200

Could it be a power issue with the line? We just moved in and it is kind of an old apartment.
 

Nitin K

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This is the stabilizer I use https://www.vguard.in/product-details/digi-200

Could it be a power issue with the line? We just moved in and it is kind of an old apartment.
The digi200 is ok for TV and small appliances and not for expensive gear.. For HT equipment avoid using it as it's voltage correction is +- 10 units.
Even I have it and have kept it only for the TV. For HT am using the Krykard 3KVA servo stabilizer and it's correction is +- 2 units. Vertex servo is also very good.
There is a thread on stabilizer on the forum. Would suggest you to go through it.
 

adakadavuley

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The digi200 is ok for TV and small appliances and not for expensive gear.. For HT equipment avoid using it as it's voltage correction is +- 10 units.
Even I have it and have kept it only for the TV. For HT am using the Krykard 3KVA servo stabilizer and it's correction is +- 2 units. Vertex servo is also very good.
There is a thread on stabilizer on the forum. Would suggest you to go through it.
oh okay but I would like to be sure it is a power problem before investing in it. We don't have any kind of fluctuations otherwise.
 

Nitin K

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oh okay but I would like to be sure it is a power problem before investing in it. We don't have any kind of fluctuations otherwise.
Yes sure, better to find out that first since the issue could be something else.
If your power is stable, try connecting directly to the mains and bypassing the digi 200.
 
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