[Don Maico]

Read somewhere that they are not suited because "of internal wiring incompatability" and yet the guy who makes TBI Diamonds speakers (and  subs} say there should be no problem, indeed he markets his Diamonds and SI class t as an item.I use mine with an active sub( not TBI) at times keeping output low just in case and it seems fine but is there a chance of "frying" the amp which is very good I think?
another thing = why 12 volt batteries instead of mains?
Thanks

[jrebman]

The TBI sub amp is a little different than most because each of the high-level inputs has a resistance of 300 ohms between them and to chassis ground so there is no chance that the negative terminals of the T-amp will short to each other or to ground.  If you don't completely trust this you can always put a series capacitor in each line coming from the outputs of the amplifier that go to the high-level inputs of the sub amp.  A film type is best, and should be somewhere between 100 uF and 200 uF -- with values near 100 uF you will start to roll off the sub-sonic frequencies, which could be a useful thing if you're getting rumble feedback from a turntable.

I ran the outputs of an original Sonic Impact T-amp directly into a Magellan 200su sub amp with no problem.  I never tried it with my Clari-T, but it is basically the same thing as far as the sub amp issue goes.

I suspect that most sub amps are not like this, so if you own something other than a TBI, you should check with the amp manufacturer to make sure there is at least 300 ohms from each terminal to ground, and between themselves.

There is a link on Vinnie's web site  which explains the benefits of SLA battery power.

Good luck,

Jim

[Vinnie R.]

Hi Don,

I moved this post to the two-channel audio forum because it does not involve a Red Wine Audio product, and it will be benefitial for more exposure to others over here (I'm sure there are lots of SI T-Amp users around here).

jrebman did a nice job answering your questions (thanks, Jim!). 

Best regards,

Vinnie

[Don Maico]

The TBI sub amp is a little different than most because each of the high-level inputs has a resistance of 300 ohms between them and to chassis ground so there is no chance that the negative terminals of the T-amp will short to each other or to ground.  If you don't completely trust this you can always put a series capacitor in each line coming from the outputs of the amplifier that go to the high-level inputs of the sub amp.  A film type is best, and should be somewhere between 100 uF and 200 uF -- with values near 100 uF you will start to roll off the sub-sonic frequencies, which could be a useful thing if you're getting rumble feedback from a turntable.

I ran the outputs of an original Sonic Impact T-amp directly into a Magellan 200su sub amp with no problem.  I never tried it with my Clari-T, but it is basically the same thing as far as the sub amp issue goes.

I suspect that most sub amps are not like this, so if you own something other than a TBI, you should check with the amp manufacturer to make sure there is at least 300 ohms from each terminal to ground, and between themselves.

There is a link on Vinnie's web site  which explains the benefits of SLA battery power.

Good luck,

Jim

Oh dear . After reading your post I quickly switched the sub off if only because I am in no way technically minded and had no understanding of what you said. This is the sub I bought albeit a rather earlier version(mk1):
https://www.bkelec.com/HiFi/Sub_Woofers/XLS200-DF.htm
The top left hand side has the high level input I use and has a special dedicated cable which connects to the T amp lft /rt and one of the negatives

[Don Maico]

Hi Don,

I moved this post to the two-channel audio forum because it does not involve a Red Wine Audio product, and it will be benefitial for more exposure to others over here (I'm sure there are lots of SI T-Amp users around here).

jrebman did a nice job answering your questions (thanks, Jim!). 

Best regards,

Vinnie

Its ok Vinnie , I wasnt sure where to put it

[Vinnie R.]

Oh dear . After reading your post I quickly switched the sub off if only because I am in no way technically minded and had no understanding of what you said. This is the sub I bought albeit a rather earlier version(mk1):
https://www.bkelec.com/HiFi/Sub_Woofers/XLS200-DF.htm
The top left hand side has the high level input I use and has a special dedicated cable which connects to the T amp lft /rt and one of the negatives

Hi Don,

Switching off the sub is not the same as disconnecting the T-amp from it.  Did you disconnect the T-amp from the sub? 

Best regards,

Vinnie

[Don Maico]

Oh dear . After reading your post I quickly switched the sub off if only because I am in no way technically minded and had no understanding of what you said. This is the sub I bought albeit a rather earlier version(mk1):
https://www.bkelec.com/HiFi/Sub_Woofers/XLS200-DF.htm
The top left hand side has the high level input I use and has a special dedicated cable which connects to the T amp lft /rt and one of the negatives

Hi Don,

Switching off the sub is not the same as disconnecting the T-amp from it.  Did you disconnect the T-amp from the sub? 

Best regards,

Vinnie

Errr no! Are you saying I shouldnt use this sub at all? :?Jan Plummer(TBI) didnt seem to think i should have a problem . Maybe I should tell him what you told me otherwise there is going to be some disappointed people out there.
Best regards
Mike

[Vinnie R.]

Hi Don,

I would explain to Jan that the outputs of the SI T-Amp are not single-ended.  Tripath does not recommend connecting the speaker outputs of their amps to the high-level inputs of their subs, even if there is some resistance between the negative terminals. 

Since the T-amp does not have volume controlled RCA output jacks (to feed the RCA inputs of your sub), you can either have it modded for this, or you might want to try something like this:
http://www.tnt-audio.com/ampli/t-preamp_e.html

Use an RCA splitter to split the volume controlled RCA output between the low-level inputs of your sub and your T-Amp.  Set the T-Amps volume control to max.  If it gets loud too quickly on the preamp's volume control, you can cut back the gain of the T-Amp but reducing its volume.

Hope this helps,

Vinnie

[Don Maico]

Since the T-amp does not have volume controlled RCA output jacks (to feed the RCA inputs of your sub), you can either have it modded for this, or you might want to try something like this:
http://www.tnt-audio.com/ampli/t-preamp_e.html

Use an RCA splitter to split the volume controlled RCA output between the low-level inputs of your sub and your T-Amp.  Set the T-Amps volume control to max.  If it gets loud too quickly on the preamp's volume control, you can cut back the gain of the T-Amp but reducing its volume.

HI VInnie
Its so difficult  for me to understand I know what an RCA splitter is: http://cpc.farnell.com/jsp/endecaSearch/partDetail.jsp?sku=CN06928 but am unsure how to use one within the context of my stereo setup.I have a coax cable I used to use for the low level input in the back of the sub when it was connected to my AV amp. Are you suggesting I should connect those somehow with the RCA cable( via splitter) that is at the moment connected to amps inputs(only one pair)?The cable I  had been using with this t amp was  supplied with the sub and screw fixes( quarter turn) into the back of the sub. Its a special cable.
The other option might be easier because i have a preamp knocking around - an Audio Innovations 800c (tube). Then again I cannot see how I can connect my sub to it as the subs connectors on the rear panel are for single cables not  pairs. The low level one is for a single coax and the high level is some other kind I have not seen before which I why I sent you that (BK) link with the pics on the back in case you might be able to enlighten me

[Don Maico]

I just read ,quote:"you should check with the amp manufacturer to make sure there is at least 300 ohms from each terminal to ground, and between themselves."from your first post. This confuses me as I only have single input to the back of my sub amp. Anyway i have emailed BK quoting the above and await a response

[Don Maico]

Just got a reply from BK:
"Our high level input has a 100K input impedance between OV and signal, but the OV are common and connected directly to ground and therefore are unsuitable for connection to the class T amp.  The only way I can see around this problem is to wire 2 x 330 ohm resistors from the class t amp to the high level lead black wire and then wire the yellow and red lead to the class t left and right outputs. You may want to run this past the manufacturer of the amplifier to make sure |I am not missing any points"
So it looks like wont be able to use the sub at the moment but will email Sonic Impact and see what they say regarding above.What I find odd is that given their incompatabilty its surprising that Sonic Impact dont warn potential purchasors of this fact. Surely there is going to be lot of disgruntled customers out there with fried T amps if they use them with active subs (I assume that is what would happen)
 

[Don Maico]

Got in touch with Jan Plummer and this his reply:
"The 330 resistors will protect the T-amp from any shorts but if it is working then you are okay.
 
Our Magellan VIP has 200 ohm resistors in each leg and work fine when connected to the t amp. There is no common ground.
 
If your sub is operating connected as you have it then there should be no forthcoming problem. As long as you don't hear any distortion there will be no problem. The t-amp claims protection against short circuits so apparently you haven't shorted anything."
 

[timothyharnett]

Why not two small subs instead of one?  That really would be a giant killer.

[Don Maico]

Why not two small subs instead of one?  That really would be a giant killer.

Its a very small room 12 ft x11ft