Anatomy of Norge 1000 GOLD Stereo Integrated Amplifier

[rishiguru]

this is for one of my friends.
budget is around 10K for the amp.

Go for Norge 1000 with eyes closed.

 

[Audiodoc]

Updated my Norge 1000 with a speaker protection circuit that I believe Mr. Bajaj should include by default. It eliminates the turn on pop as well as provides DC protection. Plus the amp doesn't continue to sing after turn of as in the stock due to stored charge in the electrolytics.

Few pics:

http://imageshack.us/f/707/52313673.jpg

 

[ganapsin]

what is the cost of the speaker protection circuit board and also model number of it.

 

[Teja]

Updated my Norge 1000 with a speaker protection circuit that I believe Mr. Bajaj should include by default. It eliminates the turn on pop as well as provides DC protection. Plus the amp doesn't continue to sing after turn of as in the stock due to stored charge in the electrolytics.

Few pics:

Imageshack - 52313673.jpg

Great job :clapping:
More details please - schematics, source of components, cost, DIY skill required etc. Would like to implement the same in both my Norges (1000 & 2060).

Thanks.

 

[quad]

Very nicely done!

 

[Audiodoc]

The speaker protection board comes for 500 bucks. Wanted to etch one for myself but I can only make single sided boards. Stumbled across the circuit from 8audio Hong Kong. Great double sided pcb. Few points to keep in mind.

1. The circuit uses 12V - 18V AC for the relays. However the problem with the Norge is that the supply voltage of the secondary is 15-0-15V so you will believe that connecting a 0-15V supply will make it work. However that seemed to be wrong. As soon I turned the power on the bridge rectifier on the PCB smoked (1A version). Then I derived the supply from the regulated DC side of the power supply board. Everything works alright now. The regulated 15V is reduced to regulated 12V by 7812 regulator on the board.

2. The results of the circuit being introduced is that the turn on pop is no more. On turning on the relays are energized indicated by the LED on the PCB. After a few second the speaker outputs get connected via the relay. Secondly the problem of music being played even after turning the amp off due to stored energy in the capacitors is also solved.

3. The circuit also provides DC protection.

If you plan to book more circuits from 8audio kindly go for a group buy. Shipping and customs will be cheaper. I have searched a lot on the net but they provide the cheapest DIY accessories. So I am in in case of group buys.

If some one plans to DIY the PCB I am in will deduce the schematics and design the same though I believe the PCB is value for money as in India it will be a toiling task to obtain all the components.

 

[Morten]

What I would love to see as a the next level of evolution for the Norge amps:

-The above mentioned speaker protection circuits.
-Higher quality speaker terminals and signal terminals
-An integrated phono stage
-Loosing the bass/treble/balance knobs. (These components do a lot more damage to sound reproduction than they do good. Every added component in the signal path acts as a filter and alters/distorts the original signal). Of course you have the Tone Defeat to bypass these components, but in my humble opinion it's better to loose them al together. This would reduce production costs, clean up the appearance of the amps and make them look all the more like serious hifi components.

-And last but not least all the above in a separate preamp/poweramp option

Just my two cents...

 

[avidyarthy]

-Loosing the bass/treble/balance knobs. (These components do a lot more damage to sound reproduction than they do good. Every added component in the signal path acts as a filter and alters/distorts the original signal). Of course you have the Tone Defeat to bypass these components, but in my humble opinion it's better to loose them al together. This would reduce production costs, clean up the appearance of the amps and make them look all the more like serious hifi components.

Agree 100% .......... have never used them till date.

 

[denom]

Have just learnt from Shyam Uncle that he is offering Separate Pre / Power Amps too. Am going to go & meet him one of these days, hopefully will get a chance to hear his new creations

 

[Audiodoc]

I am also planning on similar lines, will do the following:

Redesign the preamplifier stage with something discrete and no tone controls. Will also limit the input RCA to just one.

7mm brushed / anodized aluminum from fascia with back lit aluminum knob.

Powder coated back panel.

 

[rishiguru]

The speaker protection board comes for 500 bucks. Wanted to etch one for myself but I can only make single sided boards. Stumbled across the circuit from 8audio Hong Kong. Great double sided pcb. Few points to keep in mind.

1. The circuit uses 12V - 18V AC for the relays. However the problem with the Norge is that the supply voltage of the secondary is 15-0-15V so you will believe that connecting a 0-15V supply will make it work. However that seemed to be wrong. As soon I turned the power on the bridge rectifier on the PCB smoked (1A version). Then I derived the supply from the regulated DC side of the power supply board. Everything works alright now. The regulated 15V is reduced to regulated 12V by 7812 regulator on the board.

2. The results of the circuit being introduced is that the turn on pop is no more. On turning on the relays are energized indicated by the LED on the PCB. After a few second the speaker outputs get connected via the relay. Secondly the problem of music being played even after turning the amp off due to stored energy in the capacitors is also solved.

3. The circuit also provides DC protection.

If you plan to book more circuits from 8audio kindly go for a group buy. Shipping and customs will be cheaper. I have searched a lot on the net but they provide the cheapest DIY accessories. So I am in in case of group buys.

If some one plans to DIY the PCB I am in will deduce the schematics and design the same though I believe the PCB is value for money as in India it will be a toiling task to obtain all the components.

Audiodoc excellent work & DIY, just kindly continue this with our Indian jewel of an amp i.e Norge 1000 GOLD.:thumbsup:

My hands are heavy with my Yamaha DSP-A2070 right now, but very quickly I am going to turn my attention back to 1000.

Keep up the good work.:clapping:

 

[rishiguru]

Finally cracked into the 100 reputation points barrier. (Self proclaimed unashamed propaganda )



That too after posting only 196 posts in hifivision.hyeah:

My Rep Ratio : 196/100 = 1.96

Has anyone have a better rep ratio than me? Just for interest. :lol:

This means my every other post received a rep point. :yahoo:

Man i do not know how a noob like me get so much rep points.

I want to thank every audiophile & learned members of hifivision for giving me this opportunity and to be a part of this wonderful group of people and let me grow.

Warm Regards
rishiguru

 

[quad]

If some one plans to DIY the PCB I am in will deduce the schematics and design the same though I believe the PCB is value for money as in India it will be a toiling task to obtain all the components.

Among others, here's a simple Eagle PCB available for free -

ftp://ftp.cadsoft.de/eagle/userfiles/projects/speaker_protection.rar

Schematic

http://www.bgaudioclub.org/gallery/albums/userpics/14133/Speaker_Protection_SCH.pdf

 

[omishra]

Please also look at these DIY stuff - speaker protection kit
This could reduce your headache.
I used this, easy to install.

 

[sunder]

Re: Anatomy of Norge 2060

Teja took some great shots of Norge 2060 internals on our request.
http://www.hifivision.com/amplifiers/20340-norge-2060-internals.html

It is for his photos only that I can write this review. So, all the credit goes to Teja and not to me.

---------------------------------
Norge 2060(by Teja)

Norge 1000 & Norge 2060(by Teja)

------------------
2060 Inside view(by Teja)

2060 Pre-amplifier Module(by Teja)

Pre-amplifier Module: Both Norge 1000 & 2060 uses identical pre-amplifier modules i.e. PCB layout. Both houses three TL072 operational amplifiers but while 1000 uses Texas Instruments op-amp the 2060 uses ST Microelectronics ones. Quality wise both are same.

ST Microelectronics TL072CN(by Teja)

Like 1000, each of these three op-amps are used for bass, treble & balance management individually.

-------------------------
2060 Power-amplifier Module(by Teja)

Power-amplifier Module: Both 1000 & 2060 uses the same PCB layout + components. Like the 1000, identical CKT A1943/C5200 power transistors per channel are used. They can produce 150 watts of peak dissipation regardless of load.

2060 using A1943/C5200 power transistors(by Teja)

The calibration of the power-amp module will be different from Norge 1000, since they have different voltages feeding them.

-------------------------
The Power Supply: Here lies the big difference. Looking at the size of the toroidal transformer it seems to be at 207VA one, while the 1000's is 311VA. So, 2060 has less juice than 1000, thus less power.

2060 Toroidal Transformer(by Teja)

Toroidal Transformer Details [My guess]
VA Rating: 206.50 VA
Primary Input: AC 230V/50Hz
Secondary Output :
i) 24.5VAC x 2, 4A (Goes to the power amplifier)
ii) 15VAC X 2, .35A (Goes to the pre amplifier)

This transformer will be able to deliver:

49V X 4A = 196.00 VAC [goes to Power amps]
30V X 0.35A = 10.50 VAC [goes to Pre amps]
---------------------------
Total = 206.50 VAC = 206.50 watts ~ 207 watts

Rectifier + Ripple filters + Voltage Regulators (AC to DC PCB) (by Teja)

This module is also identical to 1000, the upper part handling the power amp module having same pair of Samwha 4700uf, 50V capacitors per channel as found on 1000.

The Ripple Filter Capacitors(by Teja)

The diodes(tiny black ones) are beefier in 1000 since it has to handle +/- 35 VAC. Here the transformer's +/- 24.5 VAC secondary for the power amp module after passing through the rectifier & power capacitors will be +/- 35 VDC, the current being 4A. With a pair of A1943/C5200 power transistors, 60 watts @ 8 ohms per channel is easily obtainable at +/- 35 VDC while using a suitable transformer.

The lower portion of the PCB for preamp module is also same, using four 1000uf caps, except that these capacitors of Norge 1000 are of a slightly better quality. The transformer's +/- 15 VAC secondary for the pre amp module after passing through the rectifier & power capacitors will be +/- 20 VDC. Now, the voltage regulator cuts down the voltage by further 10 volts, so that the DC voltage supply to the pre amp module be a 'clean' +/- 15 VDC, the current being 0.35A

Norge 2060 amps continuous power output capability

Since, 196VAC is channeled to the power amplifier module, the Norge 2060 will produce a maximum of 100 watts of continuous power at around 50~60% efficiency regardless of load.

This means Norge 2060 is always capable to provide 100 watts i.e. 50 watts of continuous power per channel to the speakers regardless of the impedance(1 ohm, 2 ohm, 4 ohm, 6 ohms, 8 ohms, ....) of the speaker. But, for safety reasons one should not use speakers below 4 ohms impedance with this amp.

Continuous Power Output of Norge 2060 :
4,6,8 ohms load : 50W X 2 = 100W

Dynamic Power Output of Norge 2060:
i) 4 ohms load : 80W X 2 = 160W
ii) 6 ohms load : 65W X 2 = 130W
iii) 8 ohms load : 50W X 2 = 100W

Wonder what difference a transformer can make.

-------------------------------------
Where Goes The Heat?

Heat Sink(by Teja)

Considering the case that Norge 2060 in Class-AB mode will deliver 100W with 50~60% efficiency, it will be dumping something around 96 watts of heat to this heat sink. A heat-sink of this size can handle a max of 60 watts of heat dissipation.

---------------------------------
Norge 1000 vs Norge 2060

1) Sound Quality : From a theoretical point of view both should be identical.

2) Continious Power Output : The Norge 1000 posses the upper hand here with 160 watts while 2060 is capable of 100 watts. The 1000 will also posses more "depth" & "warmness" in sound due to its better power output capability. The listener will always feel that the 1000 have lot in reserve and is hardly strained.

3) Dynamic Power Output : Of-course the 1000's toroidal transformer have more internal capacitance since it's bigger, which means the dynamic power rating will be much higher than 2060 at a certain load. EI transformers have even lower internal capacitance than toroidal ones. This is the reason why they are considered inferior to toroid.

CP: Continious power, DP: Dynamic Power

Say at 4 ohms loads,

Norge 1000:
CP-->160W, DP-->250W, Difference--> 250-160=90W

Norge 2060:
CP-->100W, DP-->160W, Difference--> 160-100=60W

So, the bigger the transformer the more you can push the upper ceiling(dynamic power) of the amp. NAD is famous for this.

4) Stability & Reliability : The 2060 is definitely more stable & reliable of the two.

While 1000 uses +/- 42VDC for power amp module which really pushes the power transistors & its associated circuitry to the absolute limit of their performance, Norge 2060 uses only +/- 35VDC, and thus performs in a relaxed & lazy manner. The power transistors of 2060 always operates with ease having a lot of headroom, and always remaining under the safe operating area(SOA).

Since absolute max current & voltages are supplied to the Norge 1000 power amp module to generate maximum power output that this module was designed for, I will preferably avoid 4 ohm speakers and use 6 or 8 ohm or above rated speakers with 1000. Norge 2060 will have no such problem and 4 ohm speakers can be easily used with it. These are my personal views.

Looking at the heatsink, I find Norge 1000 is dumping (300-160) = 140 watts of heat in the heat-sink, while it is capable to radiate only half of it(70 watts). To me this is critical thermal issue.

Heat assimilation of Norge 1000 heatsink = 140 - 70 = 70 watts

But for Norge 2060, (196-100) = 96 watts of heat will be dumped in the heatsink, while it is capable to radiate more than half of it(60 watts).

Heat assimilation of Norge 2060 heatsink = 96 - 60 = 36 watts

So while 1000 gets crazy as of what to do with this additional 70 watts of heat that it cannot dissipate through the heatsink at max volume thereby incrementally rising the temperature of the power transistors until they go bust, the 2060 somehow manages this 36 watts of additional heat at full volume, though this 36 watts will have a detrimental effect on the power transistors sooner or later and they will go bust too.

But then again who listens at full volume for an extended period of time? I assume no one. So, for normal listening(less than 60% volume) both amps are excellent & durable.

Considering the relaxed manner in which 2060 operates & with much better heat dissipation capability than 1000, there is no doubt that 2060 will be the preferred one for long listening duration's at high volume.

After the fan modding, Norge 1000 also becomes a very capable amp for the long listening hours at high volume.

------------------------------
Verdit :

The 2060 have more than enough power & performance to satisfy every Indian audio fanatic. But we are never satisfied, are we? For them I suggest the Norge 1000. So,

Sane & looking for normal listening pleasure : Norge 2060

Insane & looking for raw performance : Norge 1000

Not satisfied even?

Then look for Krell, NAD, Marantz, Yamaha, ....................................... the never ending list

Hi rishiguru, the anatomy of Norge is Exemplary!! Thanks. Please clarify for the internal fuse cartidges. what are the values
of the fuses of Norge 2060. What are the Ampere? Are they Slow blow or Fast blow?
Are they Small or Large? Are all the FOUR fuses same value? Any Directionality should follow to fix the fuses? Please let me know.
Thank you,
Regards,
Sunder.

 

[rishiguru]

Re: Anatomy of Norge 2060

Hi rishiguru, the anatomy of Norge is Exemplary!! Thanks.

I love that you like it sunder. Enjoy!!!

Please clarify for the internal fuse cartidges. what are the values of the fuses of Norge 2060. What are the Ampere?

Well all the five fuses used in Norge 1000 are T3AL250V.EI type. This means the fuse is rated at 3 ampere & 250 volts.

Are they Slow blow or Fast blow?

Well for sure these are slow blow fuses. i believe the "L" represents Time Lag.

Are they Small or Large?

They are of normal fuse size.

Any Directionality should follow to fix the fuses?

You can put it in any way you want. I personally have changed the direction with no effects.

 

[sunder]

Re: Anatomy of Norge 2060

I love that you like it sunder. Enjoy!!!



Well all the five fuses used in Norge 1000 are T3AL250V.EI type. This means the fuse is rated at 3 ampere & 250 volts.



Well for sure these are slow blow fuses. i believe the "L" represents Time Lag.



They are of normal fuse size.



You can put it in any way you want. I personally have changed the direction with no effects.

Thank you rishiguru, It will be helpful to me. Then, can you please let me know the availability of Best Quality Fuse Cartridges in India for the specification? If we get ceramic body fuses, that will be nice. Any Indian Brands? Did you upgrade the fuses in Norge? Seen any improvements?
Thank you,
Regards,
Sunder.

 

[sunder]

rishiguru, in Norge amplifiers, there is one Great nuisance: Cracking noise. This occurrence when the electrical swiches are put on & off. Any remedy for this? Can we do anything? This is not good for speakers' health.
Once I reported to Bajaj, but he didnt reply.
Thank you.
sunder.

 

[Audiodoc]

I have already remedied the problem of crackling noise in the norge 1000 can be done to the 2060 too. Though you can make a breadboard kit of the speaker protection circuit many ready made kits (un soldered/ soldered) are available on ebay for less than 500 bucks. I have used them in many DIY amps. Better still go for a group buy for the PCBs and procure the components from India. Doing this will cut the price below 250 bucks. Here is a pic of my no turn on pop and instant off with DC protection mod to norge 1000.

BEFORE
http://imageshack.us/photo/my-images/268/90188634.jpg/

AFTER
http://imageshack.us/f/707/52313673.jpg

I have also improved the preamplifier section. Desoldered the TL072 and put IC sockets for all three OPamp chips. Yesterday I popped in some NE5532 opamps instead and I hear a subtle change for the better. Waiting for the burr brown OPamps to land from farnell. Will post the pics of the PREAMPLIFIER mods as soon as they come.
They will also be arriving soon. Have my fingers crossed for custom clearance. Don't want to say it but they are a PIT*. DIY should be encouraged in this country.This is why thinking minds mostly flee across borders to greener pastures worldwide!

When would I hear that there is no custom duty on kits.

Hope this helps.

Next up is the up gradation to 20000 microfarad nichicons on both rails. Hope that increases the bass. THE FINAL MOD WILL BE A OPA627 BASED SWITCH ABLE PREAMP SECTION WITH A RELAY BASED SOURCE SELECTOR WHICH WILL BE ADDED IN THE NEXT MONTH AND POSSIBLY A NEW HEADPHONE AMPLIFIER SECTION. MAN THERE IS SO MUCH FREE SPACE IN THAT PAR METAL CHASSIS. IF I FIND AN ALUMINUM MILLING AND BRUSHING FACILITY IN CHANDIGARH I WILL REDESIGN THE FRONT FASCIA EVEN WITH SOLID ALUMINUM VOLUME & SOURCE SELECTOR KNOBS WITH INDICATOR LEDS AND LASER MARKING WHO NEEDS BASS, TREBLE AND BALANCE CONTROLS.

 

[murali_n]

Hi audiodoc,

I had a Norge 2060, in which the bass was a little bit leaner . When I had swapped the stock opamp to NE5532, there wasn't much of a difference in SQ, may be the OPAMP 4562 could have made it better in the pre-amp section. Also I did not try the Power caps upgrade path. Hence I upgraded my Amp to Marantz PM 6003. The difference between the two is that the Marantz has loads of Bass, is very fast, has good resolution, and a crisp treble, freq response is flat.

Anyway keep us posted, about the Capacitor upgraded performance, we will like to hear from you.

N.Murali