[c_note]

Hi, everyone.  Please take pity and help an accountant understand some of the more technical aspects of Torus products:

1)  I understand that the RM-20 has a 20 amp inlet and a 20 amp line cord is included.  Using the provided cord, can I plug this unit into a standard wall receptacle (15 amps I believe) or do I need dedicated 20 amp lines?  If I need dedicated lines, what is a reasonable estimate for how much that would cost--don't need high precision, but is this a $200 job or a $1000 job?  Is it relatively easy, or is it major surgery requiring the electrician to cut dry wall and generally make a big mess?

2)  My long term plan is to plug four items into the power conditioner: two Bryston 7B monoblocks at 600 watts each and two JL audio 12" powered subwoofers, each at 1500 watts RMS short-term.  Would an RM-15 provide enough "juice" for this load, or do I really need the RM-20?  (I have another, lesser-powered unit for other audio/video equipment.)

3) How important is voltage regulation?  I live in a condo unit in Atlanta GA, where summer temperature frequently rise into the mid-90s fahrenheit, so air conditioners are used extensively and power quality suffers--we frequently have "brown outs" and power surges.  My electrician previously told me that our building has substantial voltage fluctuation, and I frequently blow out halogen lamps in my track lighting because of this condition.  With regards to power conditioning, what does voltage regulation do, and is it worth the incremental investment?

4)  I've noticed the AVR line of Torus conditioners, but it appears this feature adds roughly 5" of depth to the unit, 22" instead of 17".  Is this correct?  22" is very deep!  As well, it seems odd that five extra inches of depth (+29%) only adds 5 pounds of weight (+5%) to the unit.  James, can you confirm?

Thanks in advance for any thoughtful replies!  This is a wonderful forum that I thoroughly enjoy reading!

[James Tanner]

Hi c-note

1. Yes the RM 20 comes with a 20 amp cord but you can also purchase an optional 20 amp to 15 amp adapter cord and that way use the 20 amp unit in a standard 15 amp circuit - my recommendation by the way.

2. The 7B can draw 7 amps each at full power into an 8 ohm load so given the subs and the 7B's you should be fine with a 15 or 20 amp Torus.

3. Voltage regulation is not critical with well designed linear power supplies.  For instance the 7B can operate from about 95 volts to 135 volts without a problem.  Switching power supplies (as used in a lot of source gear - not Bryston though) could care less what the voltage is so there is no problem there as well. My feeling is that unless you have major swings in voltage the voltage stabalization version is not required.

4. They have not release the AVR versions yet so I can not comment on the weight issue as yet.

Hope this helps.

james

[srb]

Although James and others can most likely give you real-world experiences on what you might comfortably hook up to a 15 or 20 amp unit, and you will probably never use the full 600W output of the 7Bs, do keep in mind that 600W is an output rating, not a power consumption figure.
 
Most analog amplifiers have an efficiency perhaps between 50% to 70%, and the 7B, when outputing 600W (at 8ohms - I don't know the impedance of your speakers),  consumes 1284W and 215W at idle.

[srb]

James,
 
If your spec sheet is correct, and the power cosumption at full power is 1284W @ 8ohm and 1980W @ 4ohm, would not the current draw be more on the order of 10A / 15A + ?

[James Tanner]

James,
 
If your spec sheet is correct, and the power cosumption at full power is 1284W @ 8ohm and 1980W @ 4ohm, would not the current draw be more on the order of 10A / 15A + ?

Hi,

I will check - in the past the tech guys have said about 7 amps at 8 ohms full power. I would agree with you though that these numbers are hardly ever going to be approached in normal use. Its the transient instantanious current draw that the Tous provides which is its main advantage. A typical 300 watt stereo audio power amplifier demands 10 amps RMS current from a 120 volt line (1200VA) but may demand up to 50 amp instantaneous peaks.

james

[James Tanner]

James,
 
If your spec sheet is correct, and the power cosumption at full power is 1284W @ 8ohm and 1980W @ 4ohm, would not the current draw be more on the order of 10A / 15A + ?

Here you go:

 Hi James;
 
The 7B SST2 is rated to deliver 600 Watts at 8 Ohms.  At 70% efficiency, that would calculate to about 860 Watts from the wall. Divided by 120 Volts that works out to 7.14 Amps.  We tend to assume efficiency to be closer to 50% for estimating power draw, thus the 1200+ Watts specified on the spec sheet, but at full power, efficiency is closer to 70%.  However, the 7B can deliver at least 750-800W at 8 Ohms on peaks, so peak current draw is likley to be as much as 9.5-10 Amps when operating near clipping.
 
cwr

[Gojo]

Hi C Note

Cost will depend on how "handy" you are.  I own the same Torus 20 RM unbalanced.  I was curious to see how it would improve my 4B sst2 plugged into a regular 15 receptable which was on the same breaker as about 1/4 of my house. After a 2 week break in period there was a noticeable improvement. 6 months later I decide to open the wall and eventually  run a single 12 g wire on a separate 20 amp breaker for the Torus. Actually a licensed electrican ran the wire.    I opened up the wall (2 ft by 3 ft cut; need to find the studs in order to rescrew the drypiece back in place) using a utility knife.  An electrican drilled the hole thru the floor (from the basement)  and installed the wire, breaker and receptable.  This occurred in Canada.  His time was about 1.5 hours. My time considerabley more. I was on holidays at the time (about a week)  Given he was working after hours and a friend, the cost ran round $100.  If the work has been legit, maybe $200 Cdn. I redrilled the piece of drywall in place after taping some new vapour barrier to the exisiting, taped and mudded.  Actually mudded a couple of times.  It took about a week for the Torus to regain it's "bass" back after being uunplugged for about a week.  Can't tell the corner of the living room was ever opened! Since then I have added 3 x 7sst2 to the Torus (but not the 4B). So far, so good.  I'm looking to do the the other corner.  If you don't have room in your panel, an electrician can create a subpanel and make more room.  Use the 15 amp chord until you're ready to do the upgrade.  There is a noticeable improvement in sound, particularly at higher volumes with the 20 amp service: 15 amp better; 20 amp best!  Good luck.  If you have any further questions, please ask!

[drummermitchell]

I think I'd go with the 20a also,I had a 15a with 3X7B-ssts+2X4B-ssts(all'sfine)then I figured I wanted my components separate,I ordered a 20a.MAJOR DIFFERENCE,as James says on music peaks the amps like more and I have to tell you go for the 20a it isn't much more
you'll hear a HUGE improvement,I couldn't believe it as I had to e-mail James as to what was happeneing.having power in reserve for the amps makes a huge authoritive difference.I do also have dedicated lines.when i gave my amps power in reserve,all i can say It's SHOWTIME. PS,my 15a could not give what my amps wanted,but like I say when I put the 20a with the amps,It'll scare your sheep right back into the pen .

[alexone]

James,

maybe you could give us a general recommendation what Torus we should use!?
starting from the 2B...28B amplifiers. this could be helpful for those of us who have in mind to order a Torus unit.

thanx,

al.

[James Tanner]

James,

maybe you could give us a general recommendation what Torus we should use!?
starting from the 2B...28B amplifiers. this could be helpful for those of us who have in mind to order a Torus unit.

thanx,

al.

Hi Alex,

Sounds like a good idea.  The rule of thumb though is that most source gear only needs small amounts of current so your main concern is the amplifiers and possibly the Projector (as some take a few amps).

So if you go to our website and click on the specs for each amp you have it will give you the maximum current draw at both 4 and 8 ohms.  Add those up and divide by 2/3rds.  That will give you a good real world estimate of the Torus unit required.

Remember in Europe where you are because its 230V you would need 1/2 the current that the 120 volt figures on the Bryston website give you which are based on 120 Volt.

james
 

[alexone]

thanks for your support, James!

al.