more help please....? problems with TBI sub.

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fu_man

more help please....? problems with TBI sub.
« on: 20 Dec 2007, 01:18 am »
 
Has anyone got suggestions on what my problem may be:

I added  my   sub  to the  Sig 30  RCA outputs and  got a LOT of  buzzing coming out of  my  speakers.  powering down  my  sub (quickly)  dropped  the buzz  away,  but still some noise.  and  unplugging the IC  from the sig  (obviously)  stopped the problem.

I  am  using a  TBI  passive  sub,  with a  TBI  200  sub  amp.  I  connected the  Sig  30 outputs  to the TBI amp RCA  inputs? 

[Previously I have used two subs and sub  amps coming  from the Sig speaker outputs (both mains  and sub  speakers  connectors  to the  same  posts) and  this worked  really well...  except  one  amp 'blew up'!  My  repair  guy  said it was  probably coincidence.  Repair of the TBI amp has  been long and drawn out   :cry: and  not  looking like being  fixed  any time soon  so I need a mono sub solution.  ]

(New  years  resolution - only  deal  with companies  with  stellar support   like  Vinnie!)


Vinnie R.

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Re: more help please....? problems with TBI sub.
« Reply #1 on: 20 Dec 2007, 01:32 am »

Has anyone got suggestions on what my problem may be:

I added  my   sub  to the  Sig 30  RCA outputs and  got a LOT of  buzzing coming out of  my  speakers.  powering down  my  sub (quickly)  dropped  the buzz  away,  but still some noise.  and  unplugging the IC  from the sig  (obviously)  stopped the problem.

I  am  using a  TBI  passive  sub,  with a  TBI  200  sub  amp.  I  connected the  Sig  30 outputs  to the TBI amp RCA  inputs? 


Hi fu_man,

I recommend you first try a "cheater-plug" with the TBI amp's mains power cable to disconnect the ground.  If this does not solve the problem, I suspect that there are some noise issues inside of that sub that are coupling to the RCA cables and feeding back into the Signature 30 (and then being amplified and sent to your speakers).

Quote
(New  years  resolution - only  deal  with companies  with  stellar support   like  Vinnie!)

If you are ever looking for a new sub, I HIGHLY recommend the new Omega DeepHemp:
http://www.omegaloudspeakers.com/deephemp.html

It is in an entirely different class compared to other subs I have heard used in 2-channel systems, and the price very low for such HIGH quality sound and build!  One other thing... I have one here and discovered that you can connect the speaker outputs of the Signature 30 (or 30.2) to this sub as the negative speakers posts on this sub's plate amp are not tied together (which is very common with so many other subs).  Both Louis and I have never been guys who liked subs in our 2-channel systems, but as I mentioned above, the DeepHemp is in an entirely different class!

Best regards,

Vinnie


fu_man

TBI ground loop ?
« Reply #2 on: 20 Dec 2007, 08:59 am »
Thanks Vinnie,
I  have confirmed that the  TBI  sub amp doesn't have a ground.
Actually with the sub amp switched off, no power cord, no  sub  cable  connected, but with  just the sig  RCA  outs connected to the switched off  sub amp the  hum  still occurs??  I guess that's some sort of ground  loop. funny that it hasn't happened before  although i have had the amp switched to 220 VAC now.

does proximity have any effect?


I saw Louis's subs -  seem like excellent  value!  actually i'm trying to use the  TBI's for more than just the low  freq, so  without them   my  music is  hollow :(

Vinnie R.

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Re: TBI ground loop ?
« Reply #3 on: 20 Dec 2007, 02:41 pm »
Thanks Vinnie,
I  have confirmed that the  TBI  sub amp doesn't have a ground.
Actually with the sub amp switched off, no power cord, no  sub  cable  connected, but with  just the sig  RCA  outs connected to the switched off  sub amp the  hum  still occurs??  I guess that's some sort of ground  loop. funny that it hasn't happened before  although i have had the amp switched to 220 VAC now.

does proximity have any effect?


I saw Louis's subs -  seem like excellent  value!  actually i'm trying to use the  TBI's for more than just the low  freq, so  without them   my  music is  hollow :(


Hi fu_man,

Something doesn't sound right about those RCA inputs of the sub... with the power cable disconnected from the sub, there should not be any ground loop.  You might want to first check your connections to make sure they are clean and if you have another pair of interconnects, try them out as well.  If that doesn't fix the problem, I am not sure what is going on.

Quote
does proximity have any effect?


I highly doubt it, but you might want to check this as well.

Please feel free to email me if you are still having trouble.

Quote
actually i'm trying to use the  TBI's for more than just the low  freq, so  without them   my  music is  hollow

Out of curiosity, where are you setting the sub's crossover frequency? 

Vinnie


ohenry

Re: more help please....? problems with TBI sub.
« Reply #4 on: 20 Dec 2007, 03:56 pm »
I have an SU200 and that happened once to me.  Try taking a piece of small gauge wire and touch one end to a bare metal part the SU200 (a screw head or at the vent slots) and the other to a bare spot on the amp chassis.  That did the trick for me and I made a permanent gnd connection between the two boxes (not the signal or output connections).

genjamon

Re: more help please....? problems with TBI sub.
« Reply #5 on: 20 Dec 2007, 04:11 pm »
I have a buzzing through my sub when I turn off my Sig. 30 while the wall wart is charging the batteries.  It's just some sort of transformer hum/buzz from the charger and not a grounding effect (I tried the cheater plug approach with my sub power cord to no avail).  It's not present when the Sig. 30 is powered up, nor when the charger is done with its business. 

Is it possible this is what's going on, Fu-man? 

Is this indicative of any flaws in my unit, Vinnie?  I just bought it second-hand and am thoroughly enjoying it, but you never know if something is awry when you buy second-hand.


Vinnie R.

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Re: more help please....? problems with TBI sub.
« Reply #6 on: 20 Dec 2007, 05:52 pm »
I have a buzzing through my sub when I turn off my Sig. 30 while the wall wart is charging the batteries.  It's just some sort of transformer hum/buzz from the charger and not a grounding effect (I tried the cheater plug approach with my sub power cord to no avail).  It's not present when the Sig. 30 is powered up, nor when the charger is done with its business. 

Is it possible this is what's going on, Fu-man? 

Is this indicative of any flaws in my unit, Vinnie?  I just bought it second-hand and am thoroughly enjoying it, but you never know if something is awry when you buy second-hand.


Hi genjamon,

With the Signature 30, the charger GND is tied to the GND of the RCA jacks, and it is possible that when you turn your amp off (and the charger is connected and charging), some noise will couple to the sub since since it is connected to the amp.  This is because the sub is still ON... if you were to switch it OFF, you would not have this noise.  To answer your question, nothing is wrong with your Sig 30. 

Quote
It's not present when the Sig. 30 is powered up, nor when the charger is done with its business.

Correct, because when the Sig 30 is ON, the charger is disconnected via the power toggle switch --  and when the charger is finished charging, you are going to get the noise of the charger on the GND that connects to your sub (via the RCA jacks).
The Sig 30.2 does not have this problem because the SMART module makes sure that the amplifier ground (which is the same as the RCA jack ground) is isolated from the charger ground at all times. 

Regarding the problem that Fu-Man is having, this is something totally different.  His sub is not even plugged in, but when he plugs into the RCA input jacks of his sub, he is getting noise through his speakers.... this is quite odd.


Best regards,

Vinnie

fu_man

Re: more help please....? problems with TBI sub.
« Reply #7 on: 20 Dec 2007, 11:11 pm »
Thanks  Guys!

Vinnie, that's  right, nothing  plugged in  except the interconnects,  and  I tried  two different  IC's  and the problem still  exists?
I'll  try  what  Ohenry  suggested.  If I  read that  right I  should  connect the chassis of  the TBI sub  amp to the  chassis of the Sig 30  amp.  (Bummer  is  that I  have  the  Omega  Sig  30 -  beautifully enclosed  in a  wooden case  - no  obvious   place to  connect to ground!  oh boy :?  )

Vinnie, my horns  naturally  cut off at about  150hz and the  TBI  subs  are  supposed to  be  able to  go up to   around  200hz.  (unfortunately,  I  realised a  bit  late that the matching  TBI  sub amps  only  reach to  around  150hz.) If I'm lucky it  will work out...

In the new  year  i  hope  to  engagge  an  audio consultant to  come and   measure  my  system and  help integrate the two.  May need  to  go to new  amps  and  crossovers. Hopefully he can solve this buzzing problem too  if  i can't resolve it  by then.

ohenry

Re: more help please....? problems with TBI sub.
« Reply #8 on: 20 Dec 2007, 11:22 pm »
HI fu_man,
Just touch chassis to chassis with the wire in your hands.  You'll quickly know if that will help.

Good luck! :D

Alwayswantmore

Re: more help please....? problems with TBI sub.
« Reply #9 on: 21 Dec 2007, 02:03 am »
I have one here and discovered that you can connect the speaker outputs of the Signature 30 (or 30.2) to this sub as the negative speakers posts on this sub's plate amp are not tied together (which is very common with so many other subs). 
Vinnie, assuming a Sig 30.2, do you have a recommendton for RCA vs speaker level inputs for driving the Deep Hemp???

Vinnie R.

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Re: more help please....? problems with TBI sub.
« Reply #10 on: 21 Dec 2007, 02:15 am »
I have one here and discovered that you can connect the speaker outputs of the Signature 30 (or 30.2) to this sub as the negative speakers posts on this sub's plate amp are not tied together (which is very common with so many other subs). 
Vinnie, assuming a Sig 30.2, do you have a recommendton for RCA vs speaker level inputs for driving the Deep Hemp???

Hi Kent,

Yes... if using a Sig 30 or 30.2 (with built-in volume control) with the DeepHemp, I recommend using the speaker-level inputs.  I tested it both ways and prefer the speaker-level inputs when using the DeepHemp with the Sig 30.2.

Best regards,

Vinnie




fu_man

Re: more help please....? problems with TBI sub.
« Reply #11 on: 21 Dec 2007, 10:28 am »
Oh that's odd!

I tried connecting the chassis's, it made a  difference... the  buzzing  got slightly louder.

I  shifted the amp as  far away  as  I could ... and the buzzing  dropped  by about 50%

I  unplugged the  RCA from the TBI amp and the  buzzing  continued and the other  IC too and the buzzing  got  louder?  so it seems that the buzzing comes  just  from having IC's plugged in to the  sig?
 

fu_man

SORTED!
« Reply #12 on: 21 Dec 2007, 11:11 am »
Thanks  again all!

OMG I  can't  believe how good  my speakers  are  now sounding.  Even with insufficient gain, and only mono bass.

I tried a  third  pair  of  interconnects.  All I had left  was a  $0.50c  pair of  giveaway IC... but  no more buzzing!

The  two  cables  that  gave problems are both  silver cables,  different brands and structures., but  both employ  Eichmann Bullet  Plugs.  A  cable manufacturer I know  had suggested  that if  there  was a  really  bad impedance  mis-match it  could  cause  some buzzing.... maybe  that's  what  was  wrong??

Anyway, I really appreciate  everyone's help!  Back to the  sweet  music...OMG 
 :D :D :D

Vinnie R.

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Re: SORTED!
« Reply #13 on: 21 Dec 2007, 01:56 pm »
The  two  cables  that  gave problems are both  silver cables,  different brands and structures., but  both employ  Eichmann Bullet  Plugs.  A  cable manufacturer I know  had suggested  that if  there  was a  really  bad impedance  mis-match it  could  cause  some buzzing.... maybe  that's  what  was  wrong??

Hi fu_man,

I had a good feeling that it was a bad connection.  I'm curious of those cables are simply defective (poor solder joints, broken ground, etc.).  Anyway, glad everything is working great now!  :thumb:

Happy Holidays / Happy Listening!

Vinnie