220V vs 120V - Any benefit?

[jstang]

Look who shows up.....

Go for it John! If you don't use the 220v plug for the amps you could just hall the arc welder down there! LOL Just kidding Eddie!

 

[jstang]

Ok just was doing some testing....

Signal generator set to 30 hZ sine wave

Cover off the amp to be able to measure the rail voltages.

Hand held scope to measure the outputs, rail voltages and AC signal on the rail.

8 Ohm dummy loads. Ohm Fs are 4 ohms or lower at times....

Tap in the AC power line to put a clamp type amp meter.

The AC circuit is a direct line (at least labeled that way) with only a 60watt bulb also being run on it. ALTHOUGH I NEED TO DOUBLE CHECK THAT....

Ok some measurements.... I am able to see the 60 Watt bulb dim and the AMP Power meter lamps dim when I do this.

1. Volume set to produce about 100 Watts at 8 ohms in two both channels...

2. Rails sag by 3 DC volts. With an AC component of the 1.5 volts.

3. AC line voltage sags by 3 volts

4. AC current is 5 amps.

Measurements could be off by some.... I think most of the RAIL sag is cause by the AC Line sag.


This test suggests I have a weak connection with this AC line..... But also suggests to me that 220 could help...as it should sag less.

Thoughts...?


johnk

 

[whoaru99]

Even if you could maintain rock solid input voltage, it's likely the rail voltage will sag to some degree with increasing load because the amp probably does not have a regulated PS.

 

[jstang]

Agreed it does not have a regulated supply, but seems the AC line is sagging a little more than I expected....

Even if you could maintain rock solid input voltage, it's likely the rail voltage will sag to some degree with increasing load because the amp probably does not have a regulated PS.

I need to look at that the AC line I am using... Wonder if it is weak. 15 amp breaker.

I just moved the system to the Washer/Dryer outlet which is 20amp breaker....

The system sounds slightly better at high volumes and I re-ran the 30hz test 100WPC in 8 Ohm test.... the AC voltage drop is slightly less at 2Vs.


This would all point back to the Math done by ByteWrangler as being very close to the real world.

I was not measuring the AC sag with the scope but with a DMM... So I would assume that there are some real sag spikes that are occurring that the meter was not capturing.....

So for now.... Clearly a dedicate 20amp breaker helps some, which many others have seen before.... that leads to if higher voltage will help.... I would think Bytewranlger's math would hold turn there too for extreme amp power requirements....


Now I just have to start planning the 220v circuit... I am not sure I have room for it in the breaker box..... I would hate to have to upgrade the service for just this....but its time....


jk

 

[whoaru99]

Your choice, but to upgrade an entire service panel or even put in a 22V circuit to gain one or two volts seems a bit...ehhh....extreme to me.

Heck, the line voltage fluctuates more than that over the course of a day.

 

[jstang]

That is the issue....

I really want a dedicate line for the System.... 220 or 110....

The House could use a upgraded service anyways....

Oh by the way, some one on an other site recommended using a UPS .... that it made an improvement in the sound and technically should prevent any AC sagging due to transient loads because the batteries would be a short distance from the amp.... But, a correctly sized unit will cost $$$..... Hence the 220V is the cheaper solution. Would have been real cheap if I have the room in the box....

Extreme? That is an adjective that can be used for the 500....

jk

Your choice, but to upgrade an entire service panel to gain one or two volts seems a bit extreme to me.

Heck, the line voltage fluctuates more than that over the course of a day.

Ok just was doing some testing earlier today....

Signal generator set to 30 hZ sine wave

Cover off the amp to be able to measure the rail voltages.

Hand held scope to measure the outputs, rail voltages and AC signal on
the rail.

8 Ohm dummy loads. Ohm Fs are 4 ohms or lower at times....

Tap in the AC power line to put a clamp type amp meter.

The AC circuit is a direct line (at least labeled that way) with only a 60watt bulb also being run on it. ALTHOUGH I NEED TO DOUBLE CHECK THAT....

Ok some measurements.... I am able to see the 60 Watt bulb dim and the
AMP Power meter lamps dim when I do this.

ROUND ONE OF TESTING...

1. Volume set to produce about 100 Watts at 8 ohms in two both channels...

2. Rails sag by 3 DC volts. With an AC component of the 1.5 volts.

3. AC line voltage sags by 3 volts

4. AC current is 5 amps.

Measurements could be off by some.... I think most of the RAIL sag is caused by the AC Line sag.

This test suggests I have a weak connection with this AC line..... But also suggests to me that 220 could help...as it should sag less.


ROUND TWO OF TESTING

I moved the system to the Washer/Dryer outlet which is 20amp breaker direct circuit....

The system sounds slightly better at high volumes and I re-ran the 30hz test 100WPC in 8 Ohm test.... the AC voltage drop is slightly
less at 2Vs.

I regularly drive my Ohm Fs to 200 WPC levels. So I think the results would be more pronounced.

ROUND THREE OF TESTING

I went back and opened the junction boxes for the first circuit and found two lose wire nuts... Tighten them and return the system to that circuit. The voltage drop is reduced under load...


At least I have a methodology to test along with the ears.... Based on the testing and the drops recorded...I think 220 could help.

FUTURE ROUND FOUR OF TESING

I really want a dedicate direct line for the System.... 220 or 110....Now I just have to start planning the 220v circuit... I am not sure I have room for it in the breaker box..... I would hate to have to upgrade the service for just this....but its time....

The House could use a upgraded service anyways....

You guys have any additional test methods?

FROM THIS TESTING --- I an beginning to think that the majority of supply rail sag under high load is due to AC power circuit sag --- At least for the Model 500... and its doubtful that 220v 30amp circuit will sag any wheres near what 120 15amp circuit will.... Also the amperage figures in the above testing are for a purely resistive load that required NO DAMPENING FROM THE AMP... The Model 500 has tons of dampening (>400) and the Fs need tons of dampening.... 5amps AC draw at a steady state 100WPC in 8 ohm dummy load has got to be a less demanding than 200WPC into 4 Ohm Fs.


johnk

 

[HAL9000]

marantz MODEL 500 uses 100VDC capacitors.

If i'm correct the US uses 120VAC. This is a little tight on.

BUT, i was in a conversation with a P.A studio.disco equiptment.
The amps are more important then the Voltages. :yes:
i think marantz uses 100VDC ±----> 85/90Vdc perfect alignment.

I always measure the Voltage and the Amps coming out of my amps.

and marantz 2500 and 2600 receivers came with 5.35A and 6.69A :thmbsp:
that stuff will really burn you speakers........

the 2600 right channel amplifier i re-build.

i know that crown and altec lansing made extremely big amplifiers, and both are US made... don't forget phase linear 700 (i had the 400 s2)
or SAE2600 al fantastic amplifiers with too mush power

 

[ByteWrangler]

marantz MODEL 500 uses 100VDC capacitors.

If i'm correct the US uses 120VAC. This is a little tight on.

BUT, i was in a conversation with a P.A studio.disco equiptment.
The amps are more important then the Voltages. :yes:
i think marantz uses 100VDC ±----> 85/90Vdc perfect alignment.

The capacitors are 85V, not 100, but what matters is the voltage on the secondary side of the power transformer - not the primary. If it's properly wired for the input voltage, the secondary should give the same voltage regardless of the AC voltage in. In this case it's 80V according to jstang; that's what the capacitors see.

The AC circuit is a direct line (at least labeled that way) with only a 60watt bulb also being run on it. ALTHOUGH I NEED TO DOUBLE CHECK THAT....

Ok some measurements.... I am able to see the 60 Watt bulb dim and the
AMP Power meter lamps dim when I do this.

ROUND ONE OF TESTING...
[15 A circuit?]
...

3. AC line voltage sags by 3 volts

4. AC current is 5 amps.

ROUND TWO OF TESTING

I moved the system to the Washer/Dryer outlet which is 20amp breaker direct circuit....

The system sounds slightly better at high volumes and I re-ran the 30hz test 100WPC in 8 Ohm test.... the AC voltage drop is slightly
less at 2Vs.

Those voltage drops under 5A load are way too big. Something's wrong. A fully loaded circuit (15A delivered by a 15A circuit, 20A by a 20, etc.) should have less than 5% voltage drop (<3% is recommended). You're looking at well over that. The fact that the 60W bulb dims noticeably under a moderately light load also suggests that your measurements are reasonable and something's amiss.

 

[kcollins4]

The capacitors are 85V, not 100, but what matters is the voltage on the secondary side of the power transformer - not the primary. If it's properly wired for the input voltage, the secondary should give the same voltage regardless of the AC voltage in. In this case it's 80V according to jstang; that's what the capacitors see.



Those voltage drops under 5A load are way too big. Something's wrong. A fully loaded circuit (15A delivered by a 15A circuit, 20A by a 20, etc.) should have less than 5% voltage drop (<3% is recommended). You're looking at well over that. The fact that the 60W bulb dims noticeably under a moderately light load also suggests that your measurements are reasonable and something's amiss.

Huh? Three volts drop is less than 3% of 120v. In most homes 5% is acceptable by code, because the breakers feeding the circuit are also at the main disconnect. Also, the length of the circuit can be just as large a factor in voltage drop. Unless I missed it, we don't know how far this circuit runs.

Also confused by your statement about the seconday voltage of a transformer. If the input (primary) voltage is low, the output (secondary) voltage will also be lower by the same percentage.

 

[jstang]

If it's properly wired for the input voltage, the secondary should give the same voltage regardless of the AC voltage in. In this case it's 80V according to jstang; that's what the capacitors see.



Those voltage drops under 5A load are way too big. Something's wrong. A fully loaded circuit (15A delivered by a 15A circuit, 20A by a 20, etc.) should have less than 5% voltage drop (<3% is recommended). You're looking at well over that. The fact that the 60W bulb dims noticeably under a moderately light load also suggests that your measurements are reasonable and something's amiss.

On Monday I measured the AC when I got home from work....because the Monster Power center was indicating low voltage below 110VAC....with nothing turned on....

106 Volts... It was a hot day...lots of ACs turned on... I measured it a the Main and with very little load.


Ok straight from the 500 owners manual....

100 volt configuration Range 90 to 110 VAC
120 volt configuration Range 108 to 132 VAC
220 volt configuration Range 198 to 242 VAC


Technical at 106 I was below spec....hence dim meter lights...

But yet when I measured across the two mains it still was exactly 220VAC...

I am uncomfortable with service box really want to upgrade it and secondly I don't like the one phase being 106 volts at one point today while the other stays at 114. I have seen my Monster Power center indicate low voltage before and now I know why.... I am going to call the power company and call the electrician see about upgrading the service box.


Tuesday....

Electrician came this morning and then the Power company....

Electrician: "You could use an upgrade in the service ( money in his pocket ), but from what you described the power company has problem.... No way it should be 106VAC at the main... Perhaps a bad connection or bad poll wire that needs upgrading. However, 220V is more consistent and better for higher loads. Your amp has a 15amp AC Source Fuse ?...it might benefit from the 220V."

Power Company Line Man Tech: "You measured the voltage with cheap meter, it was wrong...., we the power company have the real measuring equipment that cost thousands...., your Voltage Monitoring system ( Monster Power ) is Junk..., DID YOU MEASURE ACROSS THE PHASE? And you got 220? See there was nothing wrong.... Your electrician does not know what he is talking about...get another one....Your house is too big for the service."

Then I told him I measured 105Vac with the Mains turned off....and that stopped the BS...

He replaced the wire clamps on the service feed at the Poll and the house. They go bad over time. But I kind of doubt that will fix it. This is crappy 120V service and 220 is better.... Not unless they fixed something further down the street at the transformer.

Hehehehe.... The power company tech was fun.... I had to bite my tongue not to laugh in his face.... HE HAD ALL THE LIES LINED UP AND READY TO GO.....I have to give him credit, he was good at spinning out the BS....

I will monitor this over over time.... But clearly the system sounds better with AC staying above 118VAC now... Over the last Day & half it has not dropped below 117....

But Monster Power sells the AVS2000 that is design specific as power conditioner for audio. It corrects the sags under load. UPS will do this too... The AVS goes for about 1000$ , a used UPS about 400$ or 500$.... Parts for a 220V circuit that I install myself --- PRICELESS ( about 75$....)

But I am still charging a head with the 220VAC circuit. It cost a lot less and will be provide benefit.... Tonight I bought every thing I need to install the circuit.... 78$.... Even with using 10gauge wire. Saturday's project....


Rail voltage will track the VAC via the turns ratio that is why the VAC sag is bad for fidelity... Double affect of DC side being dragged down and then that load affect the AC side.... NO DIFFERENT THEN HAVING 30 FEET OF 20GAUGE LAMP CORD FOR THE SPEAKERS....

jk

 

[kcollins4]

Did you buy 3 conductor plus ground cable? If so, you have the option of changing it to two 120 volt circuits. Anyway, good luck with your 220v. Seems to me that's what you wanted from the start of this thread.:thmbsp:

 

[jstang]

Yes 3 plus the ground.... I was headed to the 220V from the start....but was not sure about engineering and logic.... At this point, it makes sense to me....just need to try it and see.


jk

 

[jstang]

Ok one point on how 220Vac might benefit the 500....

Straight from the 500 owners manual....

For 120Vac use a 15Amp fuse.

For 220Vac use a 10Amp fuse.


Using the standard KVA power calculation

http://www.tvss.net/train/tools/05.htm

http://www.dieselserviceandsupply.com/Power_Calculator.aspx

120V * 15amps = 1.8KVA

220V * 10amps = 2.2KVA

Steady state power draw at the rated value of the transformer.

2.2KVA / 120V = 18.33amps

The Power rating of the 500's transformer is 2.2KVA..... Not to say it will not surge to 2.2KVA with 120Vs, but the suggested 15amp back panel fuse and the 15amp circuit I am currently using for it is under sized for the possible draw of a 2.2KVA transformer.

This suggests that the 500 should be on at least a 20amp 120vac circuit and even with that the 15amp back panel fuse may start limiting it. Time Delayed fuses will allow more current for a give time frame, but start becoming a resistive bottle neck.

The typical house wiring for 15amp 120Vac wiring is 14 gauge and with multi drops at other outlets.

Also the above calculation assumes a power factor of 1. Power factor of 1 implies that the AC Voltage peak and the Current Draw peak are in Phase.... I doubt that very much with a power AMP playing music....

Makes me more convinced that 220 will help it....Saturday is the day...

I almost think Marantz chose to use a 15amp back panel fuse, so that they would not force the typical US buyer into installing a 20 amp circuit just for this amp.... I think some people would have chosen NOT to buy the 500 if it required a special circuit. On 220Vac 10amps is no problem.


johnk

 

[MudPuppy176]

The fact the factory built it with a 15A (@120v) fuse means it draws less than that at full output. Its not that large an amp. The VA rating of the transformer is moot. Its simply oversized (like most quality amps of that era). Use the wire you bought for two 20A 120V circuits and you'll be better off. By the way if you use both legs, you get 240V, not 220V. I'd bet that amp will clip long before it draws 12 amps at 120V. My MC252 only draws 10 amps.

 

[jstang]

Well lets go back check some of the numbers....It was pulling 5amps with 100WPC into 8 Ohm loads.... That was creating a 3volt ac drop on the line....

Honestly at this point, I am using/testing the 220 ( Yes 240....commonly referred to as 220 ) based on the math, reference material and testing that I have preformed.... and the 78$ it cost me.

Over sized transformer yes... but seeing the Model 500 is capable of 600WPC into 4 ohms before clipping.... I don't consider the VA rating of the Transformer to be meaningless. There are many things that I once considered to be meaningless, but have learned that paying attention to the details and understanding the principals helps in the long run.

Most amps that can not double their 8 Ohm power rating when going into 4 OHM are limited by the Transformer and other bottle necks. The 500 doubles its output from 8 to 4 Ohms.

Also, if the amp clips early, it maybe because the DC rails have sagged do due the AC side transformer sagging under the load....

What does an MC252 deliver into 4 ohms? I think with the Autotransformer output you are still producing 250WPC in 4 Ohms.

Last point of all this need for AC power....the Model 500 has a dampening factor well over 400 and I am using Ohm Fs ( 4 ohms ) which will soak dampening...High Dampening implies high servo control of the speakers by the amp, which sucks up power....

I know one of the original designers of the Ohm F....he clearly indicates the Fs need amps with tons of dampening and power to perform at their best. I know someone who blew their Mac Amp with a set of Fs due to the low Dampening factor of 40 which is into 8 ohms. One channel of amp went into oscillation, blew its output and the speaker. Usually when you half the Load you half the Dampening Factor rating. So that would be a Dampening Factor of 20 for Mac into 4 ohms. Do you know if that still holds true for the Mc252?

So loose comparisons really don't work for me, devil is in the details....Just like IF after testing, 220 (240) helps the Model 500 with a set of Fs...it may NOT help another amp with a less demanding load.... I doubt that 220 would even be needed for a Model 500 with less demanding speaker loads.

Now if you said you had a Model 500 and pair of Ohm Fs and you tried 220VAC and it did not help....well we should dig into those details more to try to understand why not.....

jk

The fact the factory built it with a 15A (@120v) fuse means it draws less than that at full output. Its not that large an amp. The VA rating of the transformer is moot. Its simply oversized (like most quality amps of that era). Use the wire you bought for two 20A 120V circuits and you'll be better off. By the way if you use both legs, you get 240V, not 220V. I'd bet that amp will clip long before it draws 12 amps at 120V. My MC252 only draws 10 amps.

 

[ByteWrangler]

Huh? Three volts drop is less than 3% of 120v. In most homes 5% is acceptable by code, because the breakers feeding the circuit are also at the main disconnect. Also, the length of the circuit can be just as large a factor in voltage drop. Unless I missed it, we don't know how far this circuit runs.

If a 15A 120V circuit sags 3 Volts under a 5A load, then it can be expected to sag 9V under full 15A load. That's 7.5%, which is way too much. If it's because the run is too long, it needs larger conductors (i.e. 12 instead of 14) to keep the drop less than 5% (or better, 3%). If it's because of a single dodgy connection, that really needs to be fixed because it may be dissipating a lot of power (up to 9V * 15A = 135W in a small area, which will get very hot).

If the voltages on the two legs are unbalanced, the problem is usually an open or poor neutral, and should be fixed. If I read jstang's post about the electrician and POCO (power company) guy right, POCO replaced some clamps on his service drop and service is back to snuff.

How big is your electric service, 'stang? If it's less than 150A and you have central A/C it probably is too small. You should seriously consider upgrading to 200A service and install the CB panel with the largest number of circuits you can get.

Also confused by your statement about the seconday voltage of a transformer. If the input (primary) voltage is low, the output (secondary) voltage will also be lower by the same percentage.

That was in regard to HAL9000's observation

"marantz MODEL 500 uses 100VDC capacitors. If i'm correct the US uses 120VAC. This is a little tight on."

which suggested to me that he thought the caps were sized for the primary voltage.

 

[jstang]

You know all you guys have really helped me dig into this to this in detail.... I greatly appreciate it.... I have been mostly on the low voltage side, not a lot on the AC side....

I have 150amp service...and agree that 200 would help the house.... I am getting a quote. But the legs were out of balance the other day 114 and 106. The stereo was on the 106... NOW THEY ARE ALMOST EXACTLY THE SAME EVERY TIME 117 to 120....

5amp & 3 Volt drop verses higher load is exactly what I was concerned with...my measurements were with a steady state of 100wpc.... I have seen 300WPCs at the speaks at the speaker with an O-scope with actual bass passages. What drops are occurring then ? I guess I could put the scope on the AC side with a slow scan and store the trace... But don't feel a need to do that...as it almost certainly is a large drop.

I did try the amp on the 20 Amp direct line for the Washer Dryer.... for the same load that produced a 3 Volt drop on the original 15amp line...there was a 2 Volt drop on the 20 amp circuit.... and that line is on the other leg..... I will reproduce the testing on the 220 line.


thanks!!!!
johnk

If a 15A 120V circuit sags 3 Volts under a 5A load, then it can be expected to sag 9V under full 15A load. That's 7.5%, which is way too much. If it's because the run is too long, it needs larger conductors (i.e. 12 instead of 14) to keep the drop less than 5% (or better, 3%). If it's because of a single dodgy connection, that really needs to be fixed because it may be dissipating a lot of power (up to 9V * 15A = 135W in a small area, which will get very hot).

If the voltages on the two legs are unbalanced, the problem is usually an open or poor neutral, and should be fixed. If I read jstang's post about the electrician and POCO (power company) guy right, POCO replaced some clamps on his service drop and service is back to snuff.

How big is your electric service, 'stang? If it's less than 150A and you have central A/C it probably is too small. You should seriously consider upgrading to 200A service and install the CB panel with the largest number of circuits you can get.

 

[whoaru99]

Last point of all this need for AC power....the Model 500 has a dampening factor well over 400 and I am using Ohm Fs ( 4 ohms ) which will soak dampening...High Dampening implies high servo control of the speakers by the amp, which sucks up power....

I know one of the original designers of the Ohm F....he clearly indicates the Fs need amps with tons of dampening and power to perform at their best. I know someone who blew their Mac Amp with a set of Fs due to the low Dampening factor of 40 which is into 8 ohms. One channel of amp went into oscillation, blew its output and the speaker. Usually when you half the Load you half the Dampening Factor rating. So that would be a Dampening Factor of 20 for Mac into 4 ohms. Do you know if that still holds true for the Mc252?

I've never heard that low damping factor on an amp blows speakers or blows the amp, nor has anything to do with oscillation. :scratch2: I think something else (EDIT: meaning not low damping factor) caused the amp to blow...


BTW, have you repeated your testing now that the service drop wires are repaired?

Actually, even a test of the 240V circuit really won't entail the evolution of the voltage drop. You'd need to have the same gauge of cable, running the same distance, except that one circuit is 120 and the other 240. That's the only way you'll get a true apples-to-apples comparison of the voltage drop between a 120 vs 240 circuit.

Of course, it could be calculated using "book" numbers for wire resistance and an arbitrary length and load, but then assumptions have to be made about connection resistances, etc.

 

[Paul C]

Do any of you know how the amp is switched from 110 to 220?

Most every dual voltage amp I've seen, there are two primary windings in the transformer. For 110/120 vac, those windings are in parallel. When the amp is plugged into 220 vac, and the voltage selection switch is switched to the 220 vac position, those windings are now in series.

The end result is... it won't make a difference. The amp will still have the same voltage (and available amperage) on the rails.

 

[whoaru99]

Yes, in theory it will be the same.

However, jstang's point is that if he cuts the voltage drop on the primary side under load there will be proportionally less rail sag on the secondary side due to the primary drop.