[smerlas]

OK let me start by saying I looked back through a bunch of previous postings on Torus and could not find the answer to this.  Search is not working the last few times I have tried .......... so if this has been addressed before I apologize.

Based on the manual for a 14BSST at full power into 8-ohms and 4-ohms respectively, the power consumption is between 10.7 and 16.5 amps @ 120v, page 9 of the on-line manual downloaded from Bryston.

Based on the manual for a 7BSST at full power into 8-ohms and 4-ohms respectively the power consumption is between 10.7 and 17.5 amps @ 120v. (for a single amp), page 9 of the on-line manual downloaded from Bryston.

First question ........... is this correct?  That is to say that a single 7BSST consumes as much power as a 14BSST?

Second question ............ 14BSST would want a 120v - 20 amp Torus unit, and will the 240v -20 amp balanced unit work? I assume the balanced unit is drawing 10 amps per leg and handles a 20 amp load? (16.5 amp plus a little head room?) And a pair of 7BSST's would want to be a wall mount unit (45 amp) or a balanced 45 amp unit?

Looking to add a Torus unit but am also planning an upgrade in amplifier from 4BSST to a 14BSST or a pair of 7BSST's.  I only want to do the Torus thing once.

While I am at it ....... are there any thoughts / opinions on a separate unit for TV, not from a current standpoint but from a high current draw versus a low current draw where voltage fluctuations are more critical.  Front end components are across the room but TV is at the same end of the room as the amp.  Since the Torus is primarily being purchased for the amp not sure if it matters if the TV is on their as well or to get the smaller 2.5 amp unit and isolate the TV.

[James Tanner]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

[James Tanner]

double entry

[drummermitchell]

It sure makes a HUGE difference making sure that your amps are getting enough amperage from the size
of Torus you pick.I went thru a couple and James straightened me out on that.
I believe you'll qiute shock at what a Torus will do for you system aa .

[drummermitchell]

 ERROR,That should be: be Quite shocked .

[werd]

Hello

James do u know if Torus has any plans on building a rm-20 or rm-15 with only one or two receptacles. I think that configuration would bring down.

thankyou

[James Tanner]

Hello

James do u know if Torus has any plans on building a rm-20 or rm-15 with only one or two receptacles. I think that configuration would bring down.

thankyou

Hi werd,

No plans on that -- in fact people usually want more inputs not less.

james

[werd]

Hello

James do u know if Torus has any plans on building a rm-20 or rm-15 with only one or two receptacles. I think that configuration would bring down.

thankyou

Hi werd,

No plans on that -- in fact people usually want more inputs not less.

james

Hi James

I know its just that it seems to me that people are dedicating these units for amps and having several inputs seems wasteful .

[95Dyna]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

Hi James,

On one of the other Torus threads Chris Russel explained that the 7B required peaks of 15 to 18 amps each or 30 to 36 both channels and the 14B up to 35 amps total (both being peak requirements).  If the RM15 and the RM20 provide up to 300 and 400 amps for peak demands I'm confused as to why you would require an RM 20 for each 7B.  Help!

[James Tanner]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

Hi James,

On one of the other Torus threads Chris Russel explained that the 7B required peaks of 15 to 18 amps each or 30 to 36 both channels and the 14B up to 35 amps total (both being peak requirements).  If the RM15 and the RM20 provide up to 300 and 400 amps for peak demands I'm confused as to why you would require an RM 20 for each 7B.  Help!

Hi Dyna,

Just to allow for other components to be used with each of the 20 amp Torus's as well without compromising the power amps. I guess if you were just going to use 'only' the amps you could get away with one 20 amp Torus.

james

[alexone]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

James,

if you are using a Torus 2.5 for your TV do really see a better picture (regarding the quality)?

al.

[James Tanner]

^

Hi Al, 

Yes the Torus removes all the noise from the powerline and improves the dynamic range of the colour.  The bigger the screen size the more effective it is. Be careful though because some of the larger projectors need a lot of current and a 120 volt 2.5 amp may not be big enough.

james

[drummermitchell]

That's why my TV is on my 60A Torus(just in case ).

[smerlas]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

James,

Thanks for the response.

Now for the follow up silly question portion of the program.  The 14BSST is available in a 15 amp and 20 amp configuration, correct?  How is it drawing 30 amps or 150% of the UL rating if purchased as a 20 amp unit.  Is the 30 amp load based on the peak reserve power required by the amp?

[James Tanner]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

James,

Thanks for the response.

Now for the follow up silly question portion of the program.  The 14BSST is available in a 15 amp and 20 amp configuration, correct?  How is it drawing 30 amps or 150% of the UL rating if purchased as a 20 amp unit.  Is the 30 amp load based on the peak reserve power required by the amp?

Hi,

We no longer offer the 14B or the 28B in a 20amp /120volt version. It takes a whole new set of Electrical standard tests and we do not sell enough of the 20 amp versions.

james

[werd]

I own a monster cable avs2000 voltage stabilizer. It has an on the fly current meter that displays current demands. I barely get over 3 amps with my 4b and my 400watt paradigm sub and thats with some pretty good volume. I know it works because when i plug a hairdyer in instaneousily reads over 12 amps. I also know that the soundstage can benefit from an ample source(overkill even) of current reserves, how much is an overkill and how much is an overkill of the overkill is confusing to me? If u calculate the max current reserves of the 4b and paradigm it comes in over 20 amps when using bryston's calculations but yet the meter on my avs2000  never reads close to that. My avs2000 is also rated at 120 amps instaneous current recovery, it never tells me when the demands are peaked as ive watched it carefully over the years. 

[SF]

I think Werd brings out a very good point. I have a 20A version of the 14B, but it is only fitted with a 15A plug for obvious reasons. I have debated the benefit that I would derive from having an electrician install a 20A line + adding a 20A Torus. I don't have any doubt that the Torus would make a big difference based on what all the owners have blogged. But how much current can one need for listening to music? Let's take Werd's 3A average draw from the plug. At 120V that translates to 360 Watts (V x I). Assuming a 90dB/W sensitivity on the speaker the 360 Watts translates to 90 + 10*(log 360/1) = 115 dB!!! A 15A plug at full draw means the amp is running at 5400 W: you are looking at 127 dB. Ouch. So if you listen at 115dB, you have enough headroom for an additional 12dB using the 15A plug. I have not taken into account heat loss etc.. this is a rough calculation. So the question remains, do I really need to upgrade from 15A to 20A wall socket and circuit?
To look at it from the other end, at most I have run my system at 100 dB (average, not accounting for transients). My speakers of 90dB/W, will then need 10 more dB. 10 = 10*(log Wf/1) where Wf stands for final Watt power. Solving for Wf, Wf = 10!! And 100 dB is pretty loud to begin with. You don't need that much current on 120V line to achieve 10W (0.08 A). Ok, let's assume 10% efficiency with heat loss etc.., you will need 0.8A to run 10W which with a 90dB/W speaker would give you 100 dB average loudness. There is still plenty head room.
My friend, who uses a 50W F5 Pass amp, used a similar argument to show me that 50W was enough power for in-home listening. I still think having ample power on board improves the sound and dynamic range. No questions there. That's why I have the 14B as opposed to the 4B for my 200W max B&W 804S speakers. But how much is too much? I am relatively new, and I may have made a mistake in my calculations. But before the electician comes, I have to justify why I need a 20A line.
Thank you for reading this somewhat long and numeric post.

[smerlas]

Hi smerlas,

The ratings in the manuals of the 7B and the 14B are RMS ratings (as opposed to peak ratings which can be 3 times as much) so the limit is the 120V/15 amp wall socket.  That's why it appears that a single 7B draws the same as a 14B.  The Stereo 14B is limited to the one wall socket whereas the MONO 7B's can be put on two different 15 amp circuits. The 14B could actually draw 2 times the power of the 7B but the 15 amp wall socket limits that.

The maximum amperage draw on a 14B is 15 amps at 8 ohms and 30 amps at 4 ohms. The 7B is 7 amps at 8 ohms and 15 amps at 4 ohms.

So I would suggest two 7B's and a 20 amp 120 volt Torus unit per 7B or go with a 230 volt 45 amp Torus unit for the 14B or the 7B's.

I use a Torus 2.5 amp unit for my TV and my Quad 2509's.

james

James,

Thanks for the response.

Now for the follow up silly question portion of the program.  The 14BSST is available in a 15 amp and 20 amp configuration, correct?  How is it drawing 30 amps or 150% of the UL rating if purchased as a 20 amp unit.  Is the 30 amp load based on the peak reserve power required by the amp?

Hi,

We no longer offer the 14B or the 28B in a 20amp /120volt version. It takes a whole new set of Electrical standard tests and we do not sell enough of the 20 amp versions.

james

Thanks again James

Since there is no local dealer I am limited to what is on the Bryston Web Site.  So if I were to purchase a 14BSST2 it would be available in a 15A/120v or 10A/240v configuration?  Is that correct?  James can you confirm what configurations are available?

Thanks

[James Tanner]

^

Hi,

Correct 15 Amp/120 Volt or 10 Amp/240Volt

james

[smerlas]

Would the 240volt version of the 14BSST require the 240 volt input - 240 output international series Torus?  If that is the case then the Torus unit could not be used to power any 120 volt front end equipment?