Puriss A1000A. Class A amp for serious listening

[denom]

Please explain a bit more about this aspect.
Joshua

As in if the source is single, you can avoid a pre-amp. Also he had attached the volume pot to the amp itself, maybe it was temporary, better Akshay clears this aspect.

 

[captrajesh]

Captain sir, take one amplifier for south region demo. So that we from the extreme south can audition and order. So that you could support an indian hifi r&d gentleman. I am interested i have also given ad for class a amp. But the audition problem and the distance and its weight is the main problem.

Thank you very much for the suggestion. Wish my budget permitted this!:sad:

 

[ravi_d]

Congrats Akshay :clapping:

Nice explanation on Class A vs Class AB.

Asking out of curiosity. Would a XLR/Balanced input make the amp more future proof? May be for those having other components in the chain with balanced connectors would make it balanced end to end.

 

[rikhav]

Hi Akshay
Congratulations on the amp build.

The build quality looks great. Will try my best to come to your place to listen to it

Regards

 

[santhosh]

Very nice build Akshay. Thanks for explaining in a simple language (not that I understood everything).

I am in Mumbai from tomorrow until Monday (will be staying in Andheri, not sure East or West yet. Hopefully close to your place). I would like to drop in for a listen. Kindly PM me your mobile number. I'll call and drop by.

Thanks in Advance.

 

[GeorgeO]

Nice build. Such locally developed products need encouragement.

 

[akshayjha]

Asking out of curiosity. Would a XLR/Balanced input make the amp more future proof? May be for those having other components in the chain with balanced connectors would make it balanced end to end.

To a certain extent, the XLR connectors do make it future proof.

However the amp can be used with a balanced source only as a mono-block. The amp does not have XLR ip's for both the channels but a single XLR. So if you want to use a balanced source with the amp you would need two power amp units, 1 unit for each channel.

I hope that answers your query.

 

[akshayjha]

Please explain a bit more about this aspect.
Joshua

3) Can be used without a pre-amp.

The gain of the amp is 26db with an input sensitivity of 1 volt. this means that you would get 50 watts of o/p power when you provide 1volt at the input.

Now, typical output levels from sources like cd players and cassette decks is 150mv-200mv. So a pre-amp would need to have a gain of around 7 so that the peak power output is reached viz 50 watts.

The purpose of a pre-amp is to:

1. Provide for source selection cd,dvd etc
2. provide a gain of around 7
3. control the signal level fed to the amp (volume).

Considering that normal listening levels is around 2-3 watts, a simple level control(volume control) between the DVD player and the amplifier is sufficient to provide enough power to the speakers.

In fact this theory forms the basis of a "Passive pre-amp", which does nothing but selects multiple sources and controls the volume. The advantage of a passive pre-amp is that it does not have any electronic circuitry.

In totality, if you want to connect a single source, this power amp can be modified to work as an integrated amplifier (by simply adding level control, which is nothing but a 50Kohm volume potentiometer)


Cheers

 

[magma]

the simplest preamp , also one of the highly regarded expensive ones is the Passion pre
when one opens it
you see how simple a preamp actualy should be
no fuss or nonsense

just a really good pot

google some pics of the passion pre

 

[keith_correa]

just a really good pot

For $1000+, I don't think there will be a pot. in there. It most likely is a Stepped Attenuator.

 

[magma]

For $1000+, I don't think there will be a pot. in there. It most likely is a Stepped Attenuator.

correct!
im an idiot when it comes to electronics

 

[santhosh]

I visited akshayjha's place yesterday afternoon to checkout his DIY Puriss amp. First thing that strikes you is its sheer size. I should have taken Denom more seriously when when he told me on the phone that the amp was HUGE!!hyeah:
Here's a pic to give you all an idea of its size.

The build quality is exceptionally good infact over engineered. The faceplate is made up of a thick 8mm aluminium sheet finished in a superb black brushed aluminum look. The chassis and casing(drilled with holes) is made up of stainless steel. Peeping through the drilled holes I could see a very neat and spacious layout of components that included two massive torroidal transformers, two large heat sinks and several huge capacitors.

Listening impressions were that the amp was very powerful and able to drive akshay's DIY speakers comfortably with ease and should be able to drive the most difficult of loads. Akshay's speakers were a very unique design in that he has used a 10 inch bolton woofer for the mids and lows and has used a v
Vifa tweeter(upto 16Khz) and a super-tweeter to cover the rest of the high frequency spectrum. I have never heard a speaker of this configuration and would really have loved to do an A/B comparison with a familiar speaker. Imaging was good except that it was as though the singer(Sade, Dianna Krall) was sitting on short stool - much shorter image than I am used to for the same songs. I think is more to do with the speakers than the amp itself. The amp has amazing headroom and never ran out of breath in driving the 10 inch driver even in difficult passages (pink Floyd - the wall and one other hindi number from that MF Hussain movie). I could feel the control and grip that the amp had on the speakers.

All in all a fantastic effort by Akshay. My recommendation to him is that he should try this amp with few other types of speakers to get a fair assessment of the amp. It would be great if members help him by carrying their speakers to his house or if Akshay can get his amp over to member's houses and also get their feedback. Akshay is very sound technically and explains queries very patiently and clearly and is super-receptive to feedback.

Thanks akshay for having me over and letting me listen to your DIY creation(s). All the very best for your future projects.

OT: It was a coincidence that Akshay lived in the same apartment complex as the friend whose marriage I was attending. The two families know each other very well and I will be meeting Akshay again at the wedding tomorrow. Small world indeed

 

[gobble]

just a really good pot

You mean "Just Really good Pot"!! hyeah:

I know the mystic in you meant that only.

Smoking weed can make the most budget'o'phile gear sound the most audiophile. :licklips:

Cheers

 

[captrajesh]

Smoking weed can make the most budget'o'phile gear sound the most audiophile.

'Pot' 'o' philia eh!!

 

[magma]

You mean "Just Really good Pot"!! hyeah:

I know the mystic in you meant that only.

Smoking weed can make the most budget'o'phile gear sound the most audiophile. :licklips:

Cheers

!
picked it up from you
one of the best ways to know fatigue free systems no?

 

[gobble]

OT: It was a coincidence that Akshay lived in the same apartment complex as the friend whose marriage I was attending. The two families know each other very well and I will be meeting Akshay again at the wedding tomorrow. Small world indeed

Wow! Small World, Yep! :clapping:

cheers

 

[denzong]

I visited akshayjha's place yesterday afternoon to checkout his DIY Puriss amp. First thing that strikes you is its sheer size. I should have taken Denom more seriously when when he told me on the phone that the amp was HUGE!!hyeah:
Here's a pic to give you all an idea of its size.

The build quality is exceptionally good infact over engineered. The faceplate is made up of a thick 8mm aluminium sheet finished in a superb black brushed aluminum look. The chassis and casing(drilled with holes) is made up of stainless steel. Peeping through the drilled holes I could see a very neat and spacious layout of components that included two massive torroidal transformers, two large heat sinks and several huge capacitors.

Listening impressions were that the amp was very powerful and able to drive akshay's DIY speakers comfortably with ease and should be able to drive the most difficult of loads. Akshay's speakers were a very unique design in that he has used a 10 inch bolton woofer for the mids and lows and has used a v
Vifa tweeter(upto 16Khz) and a super-tweeter to cover the rest of the high frequency spectrum. I have never heard a speaker of this configuration and would really have loved to do an A/B comparison with a familiar speaker. Imaging was good except that it was as though the singer(Sade, Dianna Krall) was sitting on short stool - much shorter image than I am used to for the same songs. I think is more to do with the speakers than the amp itself. The amp has amazing headroom and never ran out of breath in driving the 10 inch driver even in difficult passages (pink Floyd - the wall and one other hindi number from that MF Hussain movie). I could feel the control and grip that the amp had on the speakers.

All in all a fantastic effort by Akshay. My recommendation to him is that he should try this amp with few other types of speakers to get a fair assessment of the amp. It would be great if members help him by carrying their speakers to his house or if Akshay can get his amp over to member's houses and also get their feedback. Akshay is very sound technically and explains queries very patiently and clearly and is super-receptive to feedback.

Thanks akshay for having me over and letting me listen to your DIY creation(s). All the very best for your future projects.

OT: It was a coincidence that Akshay lived in the same apartment complex as the friend whose marriage I was attending. The two families know each other very well and I will be meeting Akshay again at the wedding tomorrow. Small world indeed

Buddy even i was at Akshay's place yesterday early afternoon. seems like i missed you by a cpl of hrs.

i fully agree to your assessment of his DIY's. all have been able to drive the class of a good quality build and performance. infact he is doing the restoration for my sansui too.

it was amazing to listen to Pink Floyd at his place

 

[santhosh]

Here's a pic to give you all an idea of its size.

Sorry, the pic did not get posted properly as I uploaded and posted from my phone. Here it is:

Checkout the size of the amp in relation to the dvd player and the iPod:thumbsup:.

 

[santhosh]

Buddy even i was at Akshay's place yesterday early afternoon. seems like i missed you by a cpl of hrs.

i fully agree to your assessment of his DIY's. all have been able to drive the class of a good quality build and performance. infact he is doing the restoration for my sansui too.

it was amazing to listen to Pink Floyd at his place

Sorry mate, would have been nice to meet you....if only I had known.

 

[captrajesh]

it was as though the singer(Sade, Dianna Krall) was sitting on short stool - much shorter image than I am used to for the same songs. I think is more to do with the speakers than the amp itself.

Hi Santosh,

I assume you are comparing the imaging with your listening experience with your B&Ws. Trust me, I was amazed at how tall the imaging was when compared to the height of the speakers. So in that respect they are special. No wonder you found that the singer was sitting on a short stool.

Yes, I too have a feeling that the Amp deserves to be heard with different speakers to experience it's true potential.

Rgds


Rajesh