Bi-Amping with Sunfire Cinema Grand???

MartinLogan Audio Owners Forum

Help Support MartinLogan Audio Owners Forum:

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
On the Sunfire Cinema Grand there are outputs for both Current and Voltage sources. As recommended from the dealer I have the current source conected to the panel (high/mid) jacks on my [ML] SL3s and the voltage source connected to the woofer (both from the respective L/R output chanels on my Sunfire).

My question is: Am I truely Bi-Amping my mains with this setup or is this the equivalent of bi-wiring them? Unless there are actually 2 amps on the front channels for the CG, I'm pretty sure this is really bi-wiring. :confused:

Main reason for asking is I am considering an Upgrade which may now be a multi channel amp to bi-AMP my mains :D

Thanks for clarifying - Jasper
 

C.A.P

Well-known member
Joined
Aug 23, 2005
Messages
2,049
Reaction score
0
Location
Michigan
Actually its a hybrids of both. The Sunfire has separate channels ! The separation is internal but it is separate. The only difference between the current source and the voltage source is a resister that changes the output impedance to sound tube-Y . If it sound good to you let it rock. I do not think that another separate box amp would do much better. Unless you went to another manufacture. The Sunfire is a great sounding amp. At least the 2 channel was I had.
 

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
Hmmm, Okay. That kinda makes sense (without going into the circuit diagram :D).

Any thoughts on moving the woofers from the main(s) output to another channel on the CG (currently powering L/R surround, I figure these could go to the back-up amp. Sounds like I may see some gain but maybe not as much as I orginally thought.

thanks!
 

sleepysurf

Well-known member
Joined
Jan 11, 2005
Messages
2,622
Reaction score
72
Location
Tampa, FL
Yes, you are "vertically bi-amping" your SL3's, which is precisely what I did with my Sunfire Cinema Grand and Aerius i's. I, too, preferred the "current" outs for the panels, and "voltage" outs for the woofers. Here's a great (though dated) review of the Sunfire Cinema Grand, with details about setting it up for bi-amping... http://www.vxm.com/21R.116.html BTW, my Sunfire is about to begin it's cross-country trek to Wisconsin, to be reunited again with (tsmooth's) Aerius i's!! As they say, what goes around, comes around!
 

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
Thanks guys. I guess I shouldn't be suprised at this point w/ Sunfire. They make some good stuff!

Appreciate the feedback - I'll now take my upgrade in another direction.

:bowdown:
 

JonFo

Super Moderator
Staff member
Moderator
Joined
Jan 16, 2005
Messages
4,675
Reaction score
402
Location
Big Canoe, GA
Jasper, in your current setup you are NOT bi-amping, you're basically bi-wiring your speakers individual elements (panel/woofer) to the current output (which adds a 1 ohm resistor to the line) and the voltage source (standard direct drive) of the same channel.

This is the same as taking a regular amp, using one wire with a built-in 1 ohm resistance to drive the panel, and another wire with no added resistance to drive the woofer.

All you are basically achieving is creating the dip at 10Khz shown in this graph of an SL3 panel with and without a 1ohm resistance in-line.


To truly bi-amp, you will need to y-split the output of your preamp and feed both the front and rear channels of the Sunfire CG the same signal, then take the current source (if you prefer a laid-back sound) and drive the panels with the front channels, then drive the woofers with the rear channels.
That means an extra amp for your rear speakers.

In either case, please ensure the SL3 speaker binding post bridge straps are removed. This is VERY important if you want an amp that works ;)
 

sleepysurf

Well-known member
Joined
Jan 11, 2005
Messages
2,622
Reaction score
72
Location
Tampa, FL
...To truly bi-amp, you will need to y-split the output of your preamp and feed both the front and rear channels of the Sunfire CG the same signal, then take the current source (if you prefer a laid-back sound) and drive the panels with the front channels, then drive the woofers with the rear channels....

Jon, if he has REMOVED the SL3 binding post bridges, and is properly running an RCA interconnect from the front to the rear channels (as described in my link above, and in the Sunfire Cinema Grand manual), it is functionally a y-split, and he is indeed vertically bi-amping. The panel and woofers are being independantly driven with completely SEPARATE amp channels.
 

Craig

Well-known member
Joined
Jan 1, 2005
Messages
1,463
Reaction score
1
Location
U.S.
The Cinema Grand is a 5 channel amp so he can truly biamp from a single component.
 

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
I went through the manuals (and the link info you guys posted). Yes I regressed back to RTFM. :rolleyes: Looks like I would need to go and bridge the inputs to another channel to truely Bi-Amp. I probably didn't describe my set-up well enough - sorry for the confusion.

Here's my current plan - dedicate my Sunfire to serving my fronts (R/C/L) and offload my rear/surrounds to an Adcom 6-channel (currently collecting dust :D). I figure the fronts (SL3/Logos) will get the most benefit from this setup. Will probably play with Bridged vs. Bi-amping the surrounds since I've got the extra channels (adcom 5006). Eventually will upgrade this to another amp (Emotiva ? :devil:) and put the adcom back to work to run audio/stereo throughout the house.

Anyone have thoughts on bi-amping surrounds vs. bridging to get more power?

Also, if I can impose one more question to the thread - I'm planning to go Balanced/XLR btwn pre & amp. The description from the manual suggests using RCA between front and 2nd channel for bi-amping (since there are 2 internally connected RCA jacks on the front L/R inputs). Would it be better to go XLR and use a Y-splitter from the pre to get balanced input to both channels I use on the Amp?

Thanks a ton for all the feedback - I've been to 2 stereo shops this week and have learned more from these post/discussions than in the 2+ hours I was in the shops.

On to the Tweaking!!!!!
 

JonFo

Super Moderator
Staff member
Moderator
Joined
Jan 16, 2005
Messages
4,675
Reaction score
402
Location
Big Canoe, GA
I went through the manuals (and the link info you guys posted). Yes I regressed back to RTFM. :rolleyes: Looks like I would need to go and bridge the inputs to another channel to truely Bi-Amp. I probably didn't describe my set-up well enough - sorry for the confusion.

Here's my current plan - dedicate my Sunfire to serving my fronts (R/C/L) and offload my rear/surrounds to an Adcom 6-channel (currently collecting dust :D). I figure the fronts (SL3/Logos) will get the most benefit from this setup. Will probably play with Bridged vs. Bi-amping the surrounds since I've got the extra channels (adcom 5006). Eventually will upgrade this to another amp (Emotiva ? :devil:) and put the adcom back to work to run audio/stereo throughout the house.

Anyone have thoughts on bi-amping surrounds vs. bridging to get more power?

Also, if I can impose one more question to the thread - I'm planning to go Balanced/XLR btwn pre & amp. The description from the manual suggests using RCA between front and 2nd channel for bi-amping (since there are 2 internally connected RCA jacks on the front L/R inputs). Would it be better to go XLR and use a Y-splitter from the pre to get balanced input to both channels I use on the Amp?

Thanks a ton for all the feedback - I've been to 2 stereo shops this week and have learned more from these post/discussions than in the 2+ hours I was in the shops.

On to the Tweaking!!!!!


Jasper, Your plan for the fronts sounds good to me.

Adcom’s do not like low impedance loads when bridged, so I’d say do bi-amping on the surrounds as well (if the Aerius supports it).

As for the balanced feed to the amp, go ahead and try feeding a balanced signal to the front channels, then use a short RCA to bridge the front channel RCA input to the rear channel RCA input. That should work. If not, there are Balanced connection Y-Splitters. I use one to feed by sub amp.
 

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
Jasper, Your plan for the fronts sounds good to me.

Adcom’s do not like low impedance loads when bridged, so I’d say do bi-amping on the surrounds as well (if the Aerius supports it).

As for the balanced feed to the amp, go ahead and try feeding a balanced signal to the front channels, then use a short RCA to bridge the front channel RCA input to the rear channel RCA input. That should work. If not, there are Balanced connection Y-Splitters. I use one to feed by sub amp.

Thanks JonFo - I didn't get the impression that the Balanced input was tied to the RCA jacks (seemed like it was kinda either/or). Will see what comes out (guessing I'll know pretty quick if no signal :eek:).

Thanks again all - will be back with a report out... wish me luck.
 

FatJ

Well-known member
Joined
Jun 18, 2007
Messages
139
Reaction score
0
Location
Houston, TX
Jasper, Your plan for the fronts sounds good to me.

Adcom’s do not like low impedance loads when bridged, so I’d say do bi-amping on the surrounds as well (if the Aerius supports it).

As for the balanced feed to the amp, go ahead and try feeding a balanced signal to the front channels, then use a short RCA to bridge the front channel RCA input to the rear channel RCA input. That should work. If not, there are Balanced connection Y-Splitters. I use one to feed by sub amp.

Please provide some info on where you picked up the XLR-Y. I need to get one of these for my descents. Thanks!
 

timm

Well-known member
Joined
Apr 30, 2005
Messages
2,085
Reaction score
4
Jasper - let me know if you try a Y adapter on your balanced out/inputs... I would be curious about that... I have a sunfire cinema sig ... and I do bi-amp my odysseys with the rca connectors as described in the manual. I don't think I've ever run it without bi-amping since that was my intention when I bought it. I used to run current/voltage for years... then I went voltage/voltage for 6 months....and now I am back to current/voltage for 3 months... I think I am going to stick with it in this configuration... Don't do the math on the watts/channel in the odysseys based on a 4 ohm load....it is....ahem....1700/channel for the signature amp.... I use this for stereo - but then have a seperate amp for movies - I use the sunfire for the center and L/R... and I have an old Carver 500t for the rears.... I wouldn't worry about bi-amping the rears.....
 

JonFo

Super Moderator
Staff member
Moderator
Joined
Jan 16, 2005
Messages
4,675
Reaction score
402
Location
Big Canoe, GA
Please provide some info on where you picked up the XLR-Y. I need to get one of these for my descents. Thanks!

I got these from Sweetwater.com, where I get most of my pro-audio gear.

If looking to split the output from a processor to feed two subs, you probably want one of these:
http://www.sweetwater.com/store/detail/YMXM2XF1/


To do what Jasper wants, then two of these: http://www.sweetwater.com/store/detail/YMXF2XM1/

would do a great job. You keep your existing balanced XLR cable, and just add this right before the amp.
 

Jasper

Member
Joined
Feb 4, 2008
Messages
14
Reaction score
0
Location
Livermore, CA
I used to run current/voltage for years... then I went voltage/voltage for 6 months....and now I am back to current/voltage for 3 months... I think I am going to stick with it in this configuration... Don't do the math on the watts/channel in the odysseys based on a 4 ohm load....it is....ahem....1700/channel for the signature amp.... :bowdown: I use this for stereo - but then have a seperate amp for movies - I use the sunfire for the center and L/R... and I have an old Carver 500t for the rears.... I wouldn't worry about bi-amping the rears.....

timm - You mention that you went back to current/voltage from v/v - was there a discernable diff?

Also - Jonfo - I just checked AVcables.net and they DON'T have any XLR Y adapters so your post is coming in very handy for all of us; I'm currently waiting on my XLR (straight) cables to arrive (they didn't come this weekend :( ). Oh, the anticipation!!!!
 

Craig

Well-known member
Joined
Jan 1, 2005
Messages
1,463
Reaction score
1
Location
U.S.
timm - You mention that you went back to current/voltage from v/v - was there a discernable diff?

Also - Jonfo - I just checked AVcables.net and they DON'T have any XLR Y adapters so your post is coming in very handy for all of us; I'm currently waiting on my XLR (straight) cables to arrive (they didn't come this weekend :( ). Oh, the anticipation!!!!

You may be able to find them and similiar XLR parts at your local Pro Audio or Guitar store.
 

timm

Well-known member
Joined
Apr 30, 2005
Messages
2,085
Reaction score
4
timm - You mention that you went back to current/voltage from v/v - was there a discernable diff?

Also - Jonfo - I just checked AVcables.net and they DON'T have any XLR Y adapters so your post is coming in very handy for all of us; I'm currently waiting on my XLR (straight) cables to arrive (they didn't come this weekend :( ). Oh, the anticipation!!!!


I would say - there is a diff - but not a HUGE diff... When I had it voltage/voltage - I would say t heard more snap crackle & pop to the sound. On Current/voltage - there was a little more space/air/ smoothness to the sound. It just depends on what you like. I like both - swore I liked voltage/voltage better - because to me it sounded like things were faster-- but then went back after I demo'd it again. I would suggest doing the same - Play it for awhile in one mode - then switch over to see what you like. better. I think both have attributes. You will love this amp... I don't know or remember if you mentioned doing any direct comparisons - but I did - and I had never heard a huge diff in an amp before. I A/Bd it to a Rotel.
 

uncle_paul

New member
Joined
Sep 20, 2022
Messages
2
Reaction score
0
Location
Washington DC
Hello, I just acquired an almost brand new Carver C-1000a that is a beast and really sounds fantastic. Since I will not be using it for cinema and want to run 2 channel, I want to Bi-Amp my speakers. Since this unit is the pre-sunfire, would the process for bi-amping this unit be the same and the sunfire? Any help is greatly appreciated!

Thanks,
Paul
 

JonFo

Super Moderator
Staff member
Moderator
Joined
Jan 16, 2005
Messages
4,675
Reaction score
402
Location
Big Canoe, GA
Does the C-1000a have preamp-level inputs for each amp? ie, a pre-out, amp-in loop?

To biamp, you will need to feed the L/R input signal to four different amps, so the unit must have some config or wiring option that allows that.
 
Top