Gehe zu Seite: Erste Letzte |nächste|

Voltage stabilizer for audio system. Which one?

+A -A
Autor
Beitrag
Neutral
Stammgast
#1 erstellt: 18. Aug 2006, 18:13
I am currently at Chennai where the voltage fluctuates like crazy (thanks to the million ACs!). What type of voltage stabilizer would you recommend for an audio system?
1. Fridge or AC stabilizer
2. Electronic stabilizer
3. Servo controlled stabilizer

Please make your suggestions soon as I need to place the order to get delivery by next month. Existing Chennai/ Bangalore forum members would be in the best position to guide me.

I didn't care about any stabilisation whilst in Bombay.

Would 1 KVA be the right capacity for an audio system?
Jeeves
Stammgast
#2 erstellt: 19. Aug 2006, 07:34
Servo is the best option. There is a make called Vertex which make them specifically suited for audiophiles, under guidance from Prithvi. You could contact Prithvi for details.
SUNILYO
Stammgast
#3 erstellt: 19. Aug 2006, 08:41
Hi,

Jeeves / Prithvi:

any idea how do they cost??
Manek
Inventar
#4 erstellt: 19. Aug 2006, 15:19
Argo servo, with an isolation transformer. They do make excellent transformers and I believe they are available in bangalore.
ALS
Ist häufiger hier
#5 erstellt: 21. Aug 2006, 08:30
as mentioned by Jeeves, Vertex is good. It comes with RF & EMI filiters built in. I'm using one 2KV, well built.
SUB_BOSS
Gesperrt
#6 erstellt: 21. Aug 2006, 08:39
People I too need one.. please help!!!!
SUB_BOSS
Gesperrt
#7 erstellt: 21. Aug 2006, 08:47

Argo servo


I found some Agro stuff here.. any idea where in bang
SUNILYO
Stammgast
#8 erstellt: 21. Aug 2006, 10:22

SUB_BOSS schrieb:
People I too need one.. please help!!!! :hail


Same for me guys
Jeeves
Stammgast
#9 erstellt: 21. Aug 2006, 12:20
Prithvi's no is 9844094669
Neutral
Stammgast
#10 erstellt: 21. Aug 2006, 17:33

Jeeves schrieb:
Servo is the best option. There is a make called Vertex which make them specifically suited for audiophiles, under guidance from Prithvi. You could contact Prithvi for details.


I got a quote for a 2KVA servo stabilizer. Rs 5300 from an industrial manufacturer based in Chennai. With 2KVA, I can power my computer, music system, and a TV all from the same stabilizer. I haven't inquired about the isolation transformer and filters for RF and EMI though. BTW, I thought that a spike guard filtered out the RF and the EMI. At least that was what was written on an MX product I bought in Bombay.

Please tell me the Vertex price. Mohan and Sunilyo if that is not affordable, I can arrange for the industrial one for you folks.
bombaywalla
Stammgast
#11 erstellt: 21. Aug 2006, 19:35

Neutral schrieb:

Jeeves schrieb:
Servo is the best option. There is a make called Vertex which make them specifically suited for audiophiles, under guidance from Prithvi. You could contact Prithvi for details.


I got a quote for a 2KVA servo stabilizer. Rs 5300 from an industrial manufacturer based in Chennai. With 2KVA, I can power my computer, music system, and a TV all from the same stabilizer. I haven't inquired about the isolation transformer and filters for RF and EMI though. BTW, I thought that a spike guard filtered out the RF and the EMI. At least that was what was written on an MX product I bought in Bombay.

Please tell me the Vertex price. Mohan and Sunilyo if that is not affordable, I can arrange for the industrial one for you folks.


2KVA is not going to be enough! Go higher - 4-5KVA. You want ample headroom for dynamics & you want this "pipe" to be a big mother of a pipe! if this pipe is constricted, forget about your system sounding good.

My brother lives in BLR & he has a 3KVA stabilizer. We discovered that his system sounds much better WITHOUT it! He admits this himself as well. However, w/ the lousy power regulation such devices are needed. I think that he now listens to his system w/o the stablizer but when he is done listening he reconnects it for safety's sake. FWIW.
Manek
Inventar
#12 erstellt: 22. Aug 2006, 06:19
Also ask about output current rating. Best to get one which can deliver near about 15 amperes of current. Remember you will be connecting multiple devices to the stabilizer each with its own current draw characteristics.

Manek.
raftuq
Ist häufiger hier
#13 erstellt: 22. Aug 2006, 06:29

bombaywalla schrieb:
I think that he now listens to his system w/o the stablizer but when he is done listening he reconnects it for safety's sake. FWIW.


When he's not listening, he connects it to protect the equipment - which presumably would be in standby or turned off? Now that's an interesting one!

Could a voltage swing (hi or lo or whatever) damage equipment that's even in standby?
SUNILYO
Stammgast
#14 erstellt: 22. Aug 2006, 07:34
Following are the things which i am going to connect to the stabilizer.

- 29" TV
- A DVD Player
- Marantz SR-4600 AVR

Maybe at a latter stage a CD player too.

So a 2 KVA wont be enough ???

Regarding filters / spike protection where can i find one in Delhi. any idea ???

I have seen locally made power strips which say they suppress spike and power surges. Do these work ???
Amp_Nut
Inventar
#15 erstellt: 22. Aug 2006, 07:39
Would be a better idea to keep the TV on a separate regulator / stabiliser.

It produces a LOT of electrical noise, which could get injected into the audio components from the common Electrical outlet at the Servo stabiliser.

Ideally, each unit should have their own noise suppression equipment.
SUNILYO
Stammgast
#16 erstellt: 22. Aug 2006, 07:50
Noise Suppression!!! are you refering to filters ?
Manek
Inventar
#17 erstellt: 22. Aug 2006, 08:35
Delhi has a good local make called Vinitech. Sturdy as a rock. I used to use large capacity UPS and stabilizers in offices and they would weather the voltage swings well. They can actually customize for 140V to 280 Volt swings, a common occurance in some places in Delhi. I think they have a website too.

manek.
bombaywalla
Stammgast
#18 erstellt: 22. Aug 2006, 14:57

raftuq schrieb:

bombaywalla schrieb:
I think that he now listens to his system w/o the stablizer but when he is done listening he reconnects it for safety's sake. FWIW.


When he's not listening, he connects it to protect the equipment - which presumably would be in standby or turned off? Now that's an interesting one!

Could a voltage swing (hi or lo or whatever) damage equipment that's even in standby?


Has this never happened to you before? It's happened to me several time esp. when I lived in a place that had lots of electrical storms preceeding the rain-fall (it was a climate much like Bombay's). Some of my equipment (TV, phone answering machine, VCR, etc) did blow out. I made the mistake of not connecting them thru a surge protector. I learnt my lesson now!!
neono
Ist häufiger hier
#19 erstellt: 22. Aug 2006, 15:30
[quote="bombaywalla"][quote="raftuq"][quote="bombaywalla"]I think that he now listens to his system w/o the stablizer but when he is done listening he reconnects it for safety's sake. FWIW.[/quote]

When he's not listening, he connects it to protect the equipment - which presumably would be in standby or turned off? Now that's an interesting one!

Could a voltage swing (hi or lo or whatever) damage equipment that's even in standby?[/quote]

Has this never happened to you before? It's happened to me several time esp. when I lived in a place that had lots of electrical storms preceeding the rain-fall (it was a climate much like Bombay's). Some of my equipment (TV, phone answering machine, VCR, etc) did blow out. I made the mistake of not connecting them thru a surge protector. I learnt my lesson now!!

I think its better to disconnect the equipment from mains during such conditions
bombaywalla
Stammgast
#20 erstellt: 22. Aug 2006, 15:40
[quote="neono"][quote="bombaywalla"][quote="raftuq"][quote="bombaywalla"]I think that he now listens to his system w/o the stablizer but when he is done listening he reconnects it for safety's sake. FWIW.[/quote]

When he's not listening, he connects it to protect the equipment - which presumably would be in standby or turned off? Now that's an interesting one!

Could a voltage swing (hi or lo or whatever) damage equipment that's even in standby?[/quote]

Has this never happened to you before? It's happened to me several time esp. when I lived in a place that had lots of electrical storms preceeding the rain-fall (it was a climate much like Bombay's). Some of my equipment (TV, phone answering machine, VCR, etc) did blow out. I made the mistake of not connecting them thru a surge protector. I learnt my lesson now!!

I think its better to disconnect the equipment from mains during such conditions [/quote]

Neono,
agree. it's better to disconnect the equipment. that's what I do. In my case the plug points are very easy to reach/access & plugging & unplugging the equipment is a few seconds job. Each time I plug & unplug I notice that the plug connections are a bit looser (i.e. they wiggle more). This is one reason I do not like to plug/unplug too often.
However, in the case for my brother the plug points in existing Indian homes (esp those that are not custom-made) are not always easily accessible. This makes it quite difficult to plug & unplug each time. More so if one listens regularly. So, out of part convenience & part laziness it has become easier to take the voltage stabilizer in/out of the loop since its rear panel is much easier to access (rather than sticking one's head under the sideboard & plugging/unplugging each time.)
raftuq
Ist häufiger hier
#21 erstellt: 23. Aug 2006, 06:50
Thanks.

On a related note: I've read someplace that you need at least 50,000 surge amp protection to keep your equipment safe from surges and spikes.

I dont recall any stabilizers or spike protectors (I have the MX spike protector strip) mentioning anything about the surge amp value. Is there some way to check it or are there brands who declare the value? And how reliable is this protection or is it notional or at best unpredictable?
screamgigi
Stammgast
#22 erstellt: 23. Aug 2006, 09:13
[warning]
Long gibberish follows
[/warning]

Which brand stabilizer?
Basically all stabilizers have the same, nasty plot inside. Some are built better, some not so.

Fortunately I live in a place where the AC main is perfectly steady. It may dip 10~15 volts in summer when the entire neighbourhood is using AC. So I don’t have much experience with stabilizer. Back in 70’s our fridge had a WIPRO servo stabilizer and I remember it was nothing remarkable.

As it appears the original poster is looking for protection from sudden and violent spikes in the line voltage. I don’t think a stabilizer is going to cut it. To the best of my knowledge a stabilizer will try to maintain a steady out of 220V in the event of under or over AC input. They do this by employing a SS sensing circuit, which will switch the transfer primary (or secondary) by a relay bank. The choice is limited, usually 3 or max 4 steps.

I don’t know how a servo stabilizer works. Maybe they have an infinite ratio input ratio to maintain a 220 Volts AC output. Is this ratio maintained by triacs?

In either case a nano-second spike will get through before the stabilizer has a chance to act. Worse a spike may trigger a violent action within the stabilizer while it tries to find it’s mooring by switching, in a quick succession, various relays to “stabilize”. So there goes your protection.

Spike Busters:
A real spike buster is sort of a kamikaze device. It will protect only once and sacrifice itself in the process. You will need to replace the passive device for protection from next spike. Not very practical in a home environment. RF circuits use a Gas Discharge Tube for spikes caused by lightenings or EMI puls. Spike buster strips that are available in the market will have a rudimentary line noise suppresser or at worst just a fuse which will try best not to blow itself up when required to do so.

Then we have expensive online UPS system. I yet do not know if they are suitable for audio equipment. I strongly believe a voltage stabilizer will adversely effect the sound quality of your amplifier.

So what is the solution? If your voltage dips or climbs at certain time of day then worry not. Equipments are designed to work to take into account a wide variation in AC line voltage. But if it spikes or fluctuates violently, then the solution is expensive online active industrial grade equipment. Or as bombaywalla-ji has suggested, disconnect your system.

But most importantly, if you are getting spikes in your AC line then you need to check your wiring right from the HT transformer that is feeding your home or apartment building. Ask your linemen to check the neutral and earth connection at both the transformer and in your home. A well-executed wiring plan will not allow spikes or dips.

I would rather look for a 1:1 isolation transformer (preferably balanced) and/or a simple Line Noise Suppressor using a few chokes, resistors and X1/Y2 Safety Capacitors across the AC line. Keep this only for your audio equipment. As Amp_Nut-ji mentioned a TV or PC can induce a lot of RF/EMI into the line.


[Beitrag von screamgigi am 23. Aug 2006, 09:20 bearbeitet]
Amp_Nut
Inventar
#23 erstellt: 23. Aug 2006, 10:56



In either case a nano-second spike will get through before the stabilizer has a chance to act. Worse a spike may trigger a violent action within the stabilizer while it tries to find it’s mooring by switching, in a quick succession, various relays to “stabilize”. So there goes your protection.



I whole-heartedly agree. The switched Tap regulators, using relays to switch diferent (auto) transformer taps, are ineffective in situations.





I don’t know how a servo stabilizer works. Maybe they have an infinite ratio input ratio to maintain a 220 Volts AC output. Is this ratio maintained by triacs?



The servo stab uses an Auto Transformer with a sliding tap, pretty much like a potentiometer.

The sliding tap is drived by a servo motor, which is driven by a difference between the reference voltage and the output voltage.

The servo motor will keep moving ( in the appropriate direction) untill the difference between the reference voltage is equal to the output voltage.

It thus maintains the output voltage, at the same level as the ref voltage.

Ofcourse there is a time lag taken to regulate. The design is always a compromise between the correction time and the overshoot / hunting of the servo motor.
Manek
Inventar
#24 erstellt: 23. Aug 2006, 15:36
There are devices called TVSS (transient voltage surge supprssor) made by APC and Emerson...would those help ?

manek.
Arj
Inventar
#25 erstellt: 23. Aug 2006, 17:46
Amp_Nut..you have a very interesting signature

I tend to agree with Gigiji and b'walla on the impact on amplifiers..the best option is a pure sinewave generator with 3-4 times the capacity of the amp to provide for Dunamic current..but boy are they expensive.

conditioners/Audio grade UPS are good for source equipment/pre amps where the variation in current is not sop much.

But I presume if you have a Class A device which is not very high power then a UPS with a much higher KVA rating should be good as the amp is anyway only going to draw constant current and the duanamic variation of output is managed only in the amp and extra dissipated as heat (This is pure self thought theory so please feel free to blow holes)

an audiophile i know in another forum used to mention that pure Class A amps are sadomasoschists..the more u abuse them the more they enjoy it
SuhasG
Ist häufiger hier
#26 erstellt: 20. Sep 2006, 14:16
[quote="Amp_Nut"][quote]

In either case a nano-second spike will get through before the stabilizer has a chance to act. Worse a spike may trigger a violent action within the stabilizer while it tries to find it’s mooring by switching, in a quick succession, various relays to “stabilize”. So there goes your protection.

[/quote]

Voltage Stabilizers (either type; Relays based or Servo) provide no protection.

Best solution is 'On Line UPS' but it will cost a bomb! 1 KVA Online UPS costs anything between 30K to 50K!!

Next best solution is to use a good quality Isolation Transformer. This guy will take care of power line surges, dips , spikes etc. 1 KVA , isolation transformer will cost around 4K.

Want to go real first class, then use an Utra Isolation transformer which has more shielding etc. (this is used for high end medical / Life support equipments, sensitive analytical/ scientific instruments) , 1 KVA Ultra Isolation Transformer will cost anything between 15K to 25K.

Midway solution is , use plain vanila Isolatiion Transfrmer (4K) and add some spike protectors (TVSS type).

It is also very important to have proper electrical earthing.
Neutral
Stammgast
#27 erstellt: 24. Sep 2006, 07:28
Perfect protection is too expensive. Some simple alternatives that I would suggest:
1. Use a spike buster strip (like MX) combined with a voltage stabiliser (preferably servo). This is what I have opted for.
2. Use a sine-wave invertor combined with a truck battery to run your music system even without mains power, for say an hour. This kind of system is in operation at the B&O showroom in Nungambakkam, Chennai.

I don't properly understand the working of an "isolation transformer". Could someone please explain.

As you folks say, stabilisers won't handle very high voltages (caused by say lightning strikes). Disconnect your equipment when not using it during the thunderstorms. Basic spike suppression technology is also built into stabilisers, as in the spike buster strips. But don't expect any magic.

From my experience, I would say that Bombay and the city areas of Chennai have fairly steady voltage. So a stabiliser is really only for peace of mind. Outside city limits, it may be a necessity. Just borrow someone's multimeter and test the voltage before deciding on this investment.
audio_engr
Ist häufiger hier
#28 erstellt: 24. Sep 2006, 19:01
I am using a Krykard Servo Voltage stabilizer (3kVA) and a Krykard Isolation transformer (2kVA) since 1989 and have no regrets. The earlier Krykard Servos used DC motors for the servo correction hence there are some maintenance issues from time to time (2-3 yrs) like replacement of brushes etc. But the newer krykards are coming with AC Servo motors nowadays. The build quality and fit-n-finish was excellent for an Indian brand but oflate Krykard have skimped on this.
Brand is Krykard, company is Alacrity Electronics, Chennai.
Neutral
Stammgast
#29 erstellt: 24. Sep 2006, 20:20
Please Audio-Engr,

Tell me what is an isolation transformer? Why do you also need it after taking a voltage stabiliser? The ratings for your protection devices are very high. Do you have a lot of electronic equipment connected to them?
SDhawan
Stammgast
#30 erstellt: 24. Sep 2006, 20:30

audio_engr schrieb:
I am using a Krykard Servo Voltage stabilizer (3kVA) and a Krykard Isolation transformer (2kVA) since 1989 and have no regrets. The earlier Krykard Servos used DC motors for the servo correction hence there are some maintenance issues from time to time (2-3 yrs) like replacement of brushes etc. But the newer krykards are coming with AC Servo motors nowadays. The build quality and fit-n-finish was excellent for an Indian brand but oflate Krykard have skimped on this.
Brand is Krykard, company is Alacrity Electronics, Chennai.



Hi !

How would you connect the equipment to these two - stabiliser & isolation transformer? Would you connect amp to stabiliser & digital source to isolation transformer or any other way?

Regards

Sanjay
SuhasG
Ist häufiger hier
#31 erstellt: 25. Sep 2006, 09:10

SDhawan schrieb:


Hi !

How would you connect the equipment to these two - stabiliser & isolation transformer? Would you connect amp to stabiliser & digital source to isolation transformer or any other way?

Regards

Sanjay


1> First connect the Servo voltage stabilizer to the regular AC mains.
2> Then connect Isolation transformer to voltage stabilizer.
3> Then Connect a terminal strip to the output of Isolation transformer.
4> Finally Connect all your Audio gear to this terminal strip.

And before anything else, check and recheck your AC mains earthing. Usually earthing wire is connected to water taps but this is not enough, earthing has to be done via specialized earthling connector (Usually a thick copper plate) which is buried in a earthling pit (2 feet deep) filled with charcoal, sand etc (to kip it dry all the time).

If required seek help from a qualified electrician.

Also it is very important to properly earth the shielding of that Isolation transformer.
SUNILYO
Stammgast
#32 erstellt: 25. Sep 2006, 11:00

SuhasG schrieb:

And before anything else, check and recheck your AC mains earthing. Usually earthing wire is connected to water taps but this is not enough, earthing has to be done via specialized earthling connector (Usually a thick copper plate) which is buried in a earthling pit (2 feet deep) filled with charcoal, sand etc (to kip it dry all the time).


Hi,

At my place the earthing has been done (as you mentioned) via water pipes connected to a borewell which goes 250 ft deep.

What are the requirements for a proper earthing:

- is it depth. The deepest the better.
- or as you mention 2 feet, will do.

Because according to my electrician you need to dig a pit almost 10 ft deep, then as u have mentioned the earthing cable should be connected to a copper plate filled with charcoal (sand, i dont know) and should be wet in order for the earthing to be stronger.

What do u say on this ??

One more thing is the earth same as the neutral ??? get confused everytime on this one.
SuhasG
Ist häufiger hier
#33 erstellt: 25. Sep 2006, 12:29

SUNILYO schrieb:

SuhasG schrieb:

And before anything else, check and recheck your AC mains earthing. Usually earthing wire is connected to water taps but this is not enough, earthing has to be done via specialized earthling connector (Usually a thick copper plate) which is buried in a earthling pit (2 feet deep) filled with charcoal, sand etc (to kip it dry all the time).


Hi,

At my place the earthing has been done (as you mentioned) via water pipes connected to a borewell which goes 250 ft deep.

What are the requirements for a proper earthing:

- is it depth. The deepest the better.
- or as you mention 2 feet, will do.

Because according to my electrician you need to dig a pit almost 10 ft deep, then as u have mentioned the earthing cable should be connected to a copper plate filled with charcoal (sand, i dont know) and should be wet in order for the earthing to be stronger.

What do u say on this ??

One more thing is the earth same as the neutral ??? get confused everytime on this one.


Depth of the pit depends on power rating (voltage and current). 2 feet is bare minimum required and of course the more deep it is better yet.

Sand , charcoal are to keep the area dry.
SDhawan
Stammgast
#34 erstellt: 25. Sep 2006, 14:51
Hi !

Don't you think you need two separate isolation transformer for the two components? And if you had a separate power amp then this would not require isolation transformer but would require high current stabiliser.

Regards

Sanjay
audio_engr
Ist häufiger hier
#35 erstellt: 25. Sep 2006, 23:42
The correct method of following the connections has been mentioned by SubhasG. This is what I follow. And as mentioned earlier, proper earthing is mandatory.

Neutral> No, I dont have too many components & oflate have simplified the system. A CDP, Single inp/Single output dual-mono Passive pre, active bass-alignment filter to convert 4th order bessel to 6th order butterworth (mono) x 2 for my Spks, a Stereo Pwr amp (Pure Class A) biwiring the Spks. Sometimes, 2 Stereo identical Pwr amps (Class A/AB) - one per spk for vertical biamping in the Summer i.e. approx 6-7 months of the year. Coming Oct '06 will shift back to Pure Class A say till end March '07.

Am totally a 2-ch guy!
screamgigi
Stammgast
#36 erstellt: 26. Sep 2006, 07:09
Using the household plumbing for safety earth is asking for serious trouble. Both for the equipment and for people who live in that home.
Amp_Nut
Inventar
#37 erstellt: 26. Sep 2006, 07:28
There IS a BIS specification on Electrical Earthing.

I had read it years ago. Very nice and detailed.

Sorry, I dont have the BIS Spec number, but you could go over to your Local BIS library / retail outlet, and they will give you the Master catalog and you can find the spec number and read it.

Cheers

Check out :

http://www.bis.org.in
SuhasG
Ist häufiger hier
#38 erstellt: 26. Sep 2006, 08:06

SDhawan schrieb:
Hi !

Don't you think you need two separate isolation transformer for the two components? And if you had a separate power amp then this would not require isolation transformer but would require high current stabiliser.

Regards

Sanjay


Isolation Transformer is for protection to entire set up. It isolates all noise, spikes, voltage transients associated with normal AC mains supply by creating the equivalent of a dedicated or isolated ground circuit. Standalone isolation transformers serve the function of removing common mode noise.

Naturally one isolation transformer (with appropriate Voltage and current rating) is enough for your entire Audio set up.
SDhawan
Stammgast
#39 erstellt: 26. Sep 2006, 11:05
Hi !

I had read somewhere that ideally you need an isolation transformer for each sensitive component or at least isolate the digital source & preamp from the power amp.

Regards

Sanjay
SuhasG
Ist häufiger hier
#40 erstellt: 26. Sep 2006, 13:58

SDhawan schrieb:
Hi !

I had read somewhere that ideally you need an isolation transformer for each sensitive component or at least isolate the digital source & preamp from the power amp.

Regards

Sanjay

This particular suggestion , that is having a separate isolation transformer for each sensitive component etc is for better sound quality.

While my suggestion about having a single Isolation Transormer for the entire audio set up , is for protecting costly audio gear from voltage spikes etc.
juggy_25
Ist häufiger hier
#41 erstellt: 26. Sep 2006, 13:59
What is a Power Conditioner? Doesnt it do the same work of the Isolation Transformer??
SuhasG
Ist häufiger hier
#42 erstellt: 27. Sep 2006, 08:43

juggy_25 schrieb:
What is a Power Conditioner? Doesnt it do the same work of the Isolation Transformer??


Power conditioner is a very loose term. It could be a simple surge suppressing passive device such a MOV or TVSS put into a nice looking box with a hefty price tag!

(I have seen a power conditioner costing $2000!)

Or it could be a solid state voltage stabilizer or even an Isolation transformer.
stevieboy
Stammgast
#43 erstellt: 27. Sep 2006, 11:37

Isolation Transformer is for protection to entire set up. It isolates all noise, spikes, voltage transients associated with normal AC mains supply by creating the equivalent of a dedicated or isolated ground circuit. Standalone isolation transformers serve the function of removing common mode noise.

Naturally one isolation transformer (with appropriate Voltage and current rating) is enough for your entire Audio set up.


hi suhas,

so what you're saying is instead of a servo stabilizer one can go in for an isolation transformer which someone mentioned was round 4 k? what specs would one need for a normal set up of the average amp and bookshelf speakers?

thanks
steve
Neutral
Stammgast
#44 erstellt: 27. Sep 2006, 15:27

stevieboy schrieb:

Isolation Transformer is for protection to entire set up. It isolates all noise, spikes, voltage transients associated with normal AC mains supply by creating the equivalent of a dedicated or isolated ground circuit. Standalone isolation transformers serve the function of removing common mode noise.

Naturally one isolation transformer (with appropriate Voltage and current rating) is enough for your entire Audio set up.


hi suhas,

so what you're saying is instead of a servo stabilizer one can go in for an isolation transformer which someone mentioned was round 4 k? what specs would one need for a normal set up of the average amp and bookshelf speakers?

thanks
steve


From what I understood, you first use the servo stabiliser and then feed its output to the isolation transformer. There are spells of low voltage (160V) in Chennai. I don't see how an isolation transformer would correct this. A servo stabiliser is most probably essential. Would add another 5K to your cost.
Neutral
Stammgast
#45 erstellt: 27. Sep 2006, 15:32

audio_engr schrieb:
The correct method of following the connections has been mentioned by SubhasG. This is what I follow. And as mentioned earlier, proper earthing is mandatory.

Neutral> No, I dont have too many components & oflate have simplified the system. A CDP, Single inp/Single output dual-mono Passive pre, active bass-alignment filter to convert 4th order bessel to 6th order butterworth (mono) x 2 for my Spks, a Stereo Pwr amp (Pure Class A) biwiring the Spks. Sometimes, 2 Stereo identical Pwr amps (Class A/AB) - one per spk for vertical biamping in the Summer i.e. approx 6-7 months of the year. Coming Oct '06 will shift back to Pure Class A say till end March '07.

Am totally a 2-ch guy!


That's simple 2-ch! Mine's real simple: a comp sound card feeding a dual-mono power amp that drives the speakers.
I am not aware of the advantage of converting filters from 4 to 6. BTW, why does the weather influence your audio setup? Just curious. What's "vertical biamping"? Usually, the mids and highs get one amp and the lows the other.
SDhawan
Stammgast
#46 erstellt: 27. Sep 2006, 15:39
Hi !

When you play your audio system you can hear your refrigerator, TV, light dimmer, mosquito repellant, cellphone charger and other elctrical devices attached to the power lines of your house. All these devices send back signals in the power lines - the electrical noise. Isolation transformer cuts out this noise by "isolating" your system. This affects the sensitive equipment like pre-amp, phono preamp, DAC, digital source, etc. as they all work with low current feeble signals. The high current devices like power amp or speaker are not affected by it so much. A power amp would be happy with just receiving ample supply of current at a stable voltage. And in fact the power amp could actually send some noise to your other components. Therefore, one should avoid putting power amp one the same isolation transformer as other components.

Regards

Sanjay
audio_engr
Ist häufiger hier
#47 erstellt: 27. Sep 2006, 21:09
Neutral> answers to your questions (though not related to the Topic - hence pls excuse fellow members).

Ques: Why use filters for 4 to 6 and advantages if any?

Ans: I use B&W Marix 802 series 2 purchased in 1990 & xover come standard with 4th Order @ 24dB/Oct Bessel alignment. This gives a low freq limit of 52Hz at +/- 2dB (free field). The speakers were designed by John Bowers (founder of B&W) to normally function without any filters. In rooms that can support podious amounts of low frequencies, the use of the Bass alignment filter was recommended by B&W. The filter with a Q=2 converts the 4th Order @ 24dB/Oct to 6th Order @ 36dB/Oct that gives a low freq limit of 27Hz +/- 2dB (free field). Also, since the limit is now 27Hz, unwanted box resonance is greatly reduced by a very steep slope @ 36dB/Oct. Hence, the low end is satisfying, deep yet a fast decay without hangs. Since the low end now with the Bass-alignment filter moved down by an octave from 52 to 27Hz, there's an apparent increase in the other extreme of the freq too, i.e. the extreme treble section which seems to develop greater amounts of air - at least to the ear.... Frankly, I see theoretially no reason why this should. All in all, wider bandwidth develops!

The filters were supplied as standard equip by B&W for models Matrix 801 & 802. In 1992, Dan D'Agustino of Krell made the same for the 801s & 802s. The circuit topology was absolutely the same as B&Ws with a Q=2 but of much tighter tolerance components, higher grade parts, much superior power supply, solid chassic etc by Krell. The design was also monoblock, 2 required for stereo. The Krell one does full justice to these speakers. I have both but use the Krells.

Ques: Why does the weather influence your audio setup?

Ans: I use an Accuphase A-60 Pure Class A Pwr amp & this beast runs hot. I have a dedicated listening room, totally treated with RPG Diffusors, so its rather difficult to manage the heat build up. Was worse when I was using Pass Labs Aleph Monos earlier. In summer, with air-conditioning, I am happy to sacrifice quality for cooler running Quad 606-II x 2.

Ques: What's "vertical biamping"

Ans: There are 2 ways you can bi-amp. In both these cases, the 2 Pwr amps must be identical.
(1) Stereo Pwr amp A drives the speakers LF (L & R) while Stereo Pwr amp B drives the speakers HF (L & R). This is known as HORIZONTAL biamping.
(2) Stereo Pwr amp A drives only the Left Spk - amp L-ch for LF & R-ch for HF. Similarly, Pwr amp B drives the Right Spk in the same fashion. This is VERTICAL biamping.

There's an obvious advantage in vertical biamping, the arrangement allows you monoblocking - an independent amp with its power supplies per Speaker. Hence, no power supply sharing between input Left & Right signal channels, leading to better dynamics, transients, reduced clipping etc. Also, monoblocking gives superior channel separation.

Hope I've answered your queries entirely.

SDhawan> I fully second you that isolation transformer is not necessary for high voltage/high power devices. I have a Servo, followed by an isolation transformer. My low voltage devices are plugged after the isolation transformer. My pwr amp only uses the servo.
SDhawan
Stammgast
#48 erstellt: 28. Sep 2006, 07:55

There's an obvious advantage in vertical biamping, the arrangement allows you monoblocking - an independent amp with its power supplies per Speaker. Hence, no power supply sharing between input Left & Right signal channels, leading to better dynamics, transients, reduced clipping etc. Also, monoblocking gives superior channel separation.


Hi !

Don't you think that in vertical bi-amping driving HF & LF drivers may distort each other's signal - this is minimsed in horizontal bi-amping.

Regards

Sanjay
Arj
Inventar
#49 erstellt: 28. Sep 2006, 08:39

SDhawan schrieb:


Hi !

Don't you think that in vertical bi-amping driving HF & LF drivers may distort each other's signal - this is minimsed in horizontal bi-amping.

Regards

Sanjay



what mono blocking achieves to remove is crosstalk.vertical Bi amping would still have crosstalk so not sure if that would improve on that. what biampind does is give more power hence in systems requiring more power there is an apparent benefite. you may get no benefit in a high sensitivity setup from vertical bi amping.

but again many preamps are equally susceptible to crosstalks


regarding power amps i remember reading a theory that that output power of the power amp is purely the input power but modulated by the control signal in the source/pre (any of the technical gurus please do correct me)

hence power in - is the signal which goes to the speaker ..only modulated by the musical signal. hence dirty power into the amp directly gets fed intto the speaker. My understanding of the reason for not having power amps in the "regulated" circut is the since amplifier requirement is very dynamic, most regulators are unable to keep up with this dynamic reequirement thur robbing the music out of air and urgency.

you should not have the problem in SETs due to low power requirements and in Pure class As as they always draw constant current..as long as the power rating is much higher than the power rating of the amp.
Neutral
Stammgast
#50 erstellt: 28. Sep 2006, 17:16
Thanks Audio Engr, for the detailed reply
I will desist from asking you any further questions as it will scare away noobs from this thread I started. BTW, my amp is dual mono and in a sense my speakers are vertically biamped too. But separating the kick-back from the woofer from the tweeter's input is the usual objective of biamping, which benefit I certainly won't obtain.

27Hz. Wow! Wish I could listen to a church organ or double bass at your place. Glad you roll it off so quick (6th order) or the poor drivers would fry

Your amp acts as a hotplate - great for winter but I wouldn't want it in Chennai. I'd get tanned. If you halved the lowest freq to which your speakers will go, you quadrupled the power the amp will have to put out - if my maths is correct. I guess you rein in the volume to compensate.

To return to the original post of mine, my supplier tells me that a 2KVA servo stabiliser is sufficient for an audio system, so that's what I've taken.
SDhawan
Stammgast
#51 erstellt: 28. Sep 2006, 18:22
Dear Neutral,

The reccomendation here is to total all the max power requirement of your current & future components and then add 50 % to it to determine what you should go for.

Regards

Sanjay
Suche:
Gehe zu Seite: Erste Letzte |nächste|
Das könnte Dich auch interessieren:
Voltage stabilizer
cheraz am 02.02.2004  –  Letzte Antwort am 03.02.2004  –  8 Beiträge
Voltage Converter for nad320bee amplifier.
Hemanth am 17.01.2005  –  Letzte Antwort am 18.01.2005  –  2 Beiträge
Which portable cd-system?
erikek am 05.02.2006  –  Letzte Antwort am 17.02.2006  –  9 Beiträge
Which Interconnect ?
abhi.pani am 31.07.2006  –  Letzte Antwort am 10.08.2006  –  50 Beiträge
which Speaker with which amp?
Manags am 28.10.2005  –  Letzte Antwort am 29.10.2005  –  6 Beiträge
Recommendations for audio setup
Nagaraj am 18.11.2004  –  Letzte Antwort am 22.11.2004  –  9 Beiträge
Which Headphones?
soulforged am 21.09.2006  –  Letzte Antwort am 11.10.2006  –  25 Beiträge
Can I use UPS for Protection of my Stereo
abhi.pani am 15.07.2006  –  Letzte Antwort am 24.07.2006  –  33 Beiträge
which ones are better?
VivekMansata am 24.11.2007  –  Letzte Antwort am 29.11.2007  –  12 Beiträge
Voltage conversion
mmx_2 am 25.12.2004  –  Letzte Antwort am 28.12.2004  –  11 Beiträge
Foren Archiv

Anzeige

Aktuelle Aktion

Partner Widget schließen

  • beyerdynamic Logo
  • DALI Logo
  • SAMSUNG Logo
  • TCL Logo

Forumsstatistik Widget schließen

  • Registrierte Mitglieder925.736 ( Heute: 11 )
  • Neuestes Mitgliedwonieryn
  • Gesamtzahl an Themen1.551.115
  • Gesamtzahl an Beiträgen21.538.480

Hersteller in diesem Thread Widget schließen