Connect Sub to Cambridge Evo 150

[Slash86]

Hello!

Thanks to the great advice from your fellow forum members, im now the proud owner of a Cambridge EVO 150 and a pair of KEF LS50 Meta. I am not going to start some extensive comments about the audio Nirvana im currently in, having moved from Headphones setups to this very first high quality hifi.... i would continue for days. Im just in heaven.

Also thanks to the (now terrible advice as this was way out of budget )) advices i got here, i have also purchased a SVS 3000 Micro to complete this blissful setup.

I have not yet received and never used a sub before, but I am a little curious. I understand the sub can be connected either using the pre-out or using the subwoofer out. Now, i am wondering what would be the best approach?
One could think that sub out is the way to go, but i havent found any EQ or setup on the EVO 150 that would allow to have a hand on the signal sent to the sub. It feels like if i use the sub out, i will just have to go with whatever the Cambridge EVO's crossover does , with no hand on it. Whereas if i were to use the pre out , then i could use the sub crossover and play more finely with the cut frequency.

I must be missing something, but i do not see the added value of using the sub out compared to pre out ... and since it seems counter intuitive , i must be missing something.

Would anyone be able to explain to the newbie that i am why it would make more sense to use the sub-out rather than the pre-out ?

 

[ad_fletch]

I realise this is a month late, but hey you said you were still waiting for the sub so maybe it'll still be useful.

IIRC the sub out rolls off at 500Hz or so, which means (as you say) you'll need to use the low pass filter built into your sub anyway. I'd check in the manual, but the CA site won't let me download it for some reason.

One further thought is that the sub out is probably summed to mono (ie takes low frequency info from R & L channels and mixes it), which means you only need 1 cable from it to your LFE input.

Someone more knowledgeable will surely chime in with a more compelling reason (or to correct me), but hope that's some help.

 

[Mauiboy]

Coincidentally, I bought the Evo 150 and SVS 3000 Micro recently. I've just finished configuring the SVS 3000 Micro and equalizing it using REW and thought I'd post some notes.

The SVS 3000 Micro (just SVS from here on) manual says, when using LFE input on the plate amp, the low-pass filter is not used. And in fact, the SVS app does not allow the SVS crossover to be configured, if the LFE input is enabled.

An Dolby Digital LFE (low-frequency effects) source channel has a particular specification that the input signal is band limited to 120 Hz and is boosted relative to any single main channel speaker (in a Dolby Digital movie theater or home theater setup)...

https://www.dolby.com/uploadedFiles/Assets/US/Doc/Professional/38_LFE.pdf

The LFE channel carries additional bass information to supplement the bass information in the main channels. The signal in the LFE channel is calibrated during soundtrack production to be able to contribute 10 dB higher SPL than the same bass signal from any one of the screen (front) channels.

:

The subwoofer output, on the other hand, is bass information from up to all six channels that has been selected to be reproduced by a subwoofer. The specific combination of bass information in the subwoofer output is determined by the bass management settings chosen for that particular playback system’s speakers.

:

As can be seen from the above explanation, the terms LFE and subwoofer are not interchangeable, and the distinction between the two terms is very important.

Oddly, Cambridge Audio provides no bass management configuration for the Evo in the StreamMagic app and there are no settings on the front panel of this device. The only TV related setting is to allow the TV to command the Evo to wake from standby. The Evo sub out connector is lavender in color, implying that it follows the THX specification for LFE. But I wonder, and the manual is completely silent on this subject.

So if I choose a HDMI ARC input, I would expect the LFE channel to be combined in some undocumented way with the other channels in the TV audio source and presented to the Sub-Out connector. And if I choose a two-channel source (like Roon, CD, or LP), I would expect the sub-out to produce a signal sum of the two main channels, band limited at some undocumented rate and with an undocumented crossover point.

Without in-built bass management, and with only a Dickensian sliver of documentation for this $3,000 product, we are left to either guess or measure.

I placed the sub in a "double corner" (45 degrees to the corner of a column that sits in one corner of the living area). In this position, the two 8" active drivers fire at angles to the side and front walls of the room and it sits about 2' from each of the two corners on sides of the column.

I'm using SVS SoundPath wireless subwoofer kit, a pair of transmitter and receiver units. The SoundPath can accept and pass a full-range stereo signal, without compression, and with very low latency. For simplicity, I've connected the Evo lavender Sub-Out connector to a single channel of the SoundPath transmitter, using the provided mono RCA-TRS connector. I have no idea which channel is being used, and it doesn't matter. I've then connected the SoundPath receiver to the SVS using the matching TRS-RCA mono cable, and I've jacked it into the LFE input on the SVS and activated LFE mode in the SVS app, which disables the manual crossover adjustment.

I used REW to qualify the full-range signal that I fed via AirPlay2 to the Evo and measured with the UMIK-1. I manually set the gain in the SVS using the iOS app to roughly blend with the main speakers (Monitor Audio CS-180 in-ceiling speakers, two on the left channel, and two on the right, using the Evo's "A" binding posts).


The little SVS 3000 is a monster! At the default gain setting of -10db, it was way too loud! The living room is 18' x 30', open on two sides and this little sub is more than adequate. Balanced gain across the spectrum came at about -25db (set in the SVS app). The SVS has three band PEQ in-built to the plate amp. So I want to use REW to select the filter coefficients.

First, I did a quick measure and see the SVS response rolling off at 200 Hz.

So this Evo Sub-Out is not LFE, when playing a two-channel source, but rather a sum of the left and right channels. I can't tell from this whether the band limiting is in the SVS or in the Evo (or likely in both). (Perhaps someone with both an Evo and an Audio Precision instrument can determine what's coming out of the Evo Sub-Out port for 2-channel and Dolby ARC signals.)

So there are a few nodes and a couple of modes to tackle, but otherwise, not bad!

I set the target to the lower edge of the measured response line, with the room curve I've been using. I opened REW's EQ panel and unchecked all but 5 of the filters and then ran the Match Response to Target. When looking again at the EQ panel, I selected the three best adjustments and turned off the others. Then ran the Optimize gains and Q's. And experimented with iterating these optimizations (not the same results each time!)

I got a nice prediction in the end, and loaded the coefficients of the three selected bands into the SVS app PEQ settings page. Here's an example of the first PEQ loaded into the app:

Then with the SVS configured, I re-ran a full-speaker, full-range measure and generated a correction filter. This I loaded into Roon.

Up to 10K, this is good. I had to make one manual gesture in the EQ settings. I applied a High Shelf at 2K to bring up the treble response. My listening position is within the matrix of ceiling speakers. The speakers have aimable tweeters, but they only pivot so far. It is not possible to get a better treble response without standing under the speaker! Given this is a living room, not a home theater, I have limited options for what I can bring into the room.

So with Roon providing the convolution (and with a few db of headroom protection) it sounds very good! Even with the lack of high-frequency response within this listening area, the sound is very musical with the dampening of treble more a function of the room and listening position.

The SVS brings deep bass extension that I've never experienced in the living room before. It is not boomy, just tight and reactive. Acoustic bass tracks are just remarkable. Brian Bromberg "Wood" is a reference here. Hand plucked 300-year old upright double bass. I also listened to Tchaikovsky's Nutcracker Suite (given the opening of holiday season is upon us), and at elevated listening volume the bass never overpowers, and the Evo never sounds "dangerous". Sonically lovely.

I'm very grateful to this community for your sharing of experience. I hope this description of my first attempt at subwoofer equalization and room correction is somewhat helpful. This is a work in progress and I expect I'll do this all over again when I learn more. And I'd be grateful for any impressions the community has or suggestions (other than to move my furniture to restore the treble!)


Some impressions of the SVS:

• The plate amp is a monster: 800 watts RMS class-D. All that power comes from a switching power supply in-built to the unit. And it makes audible noise even at idle. It's like an old PC power supply, if you get up close to it. (In my case that would mean crawling under the piano, something I'm not going to do very often.) But be aware. If you put this thing in a bedroom corner with a hardwood floor, you'd likely hear it sparkling along during the night. It does this even on "standby." Might be worth a conversation with SVS support as to whether this is normal.
• And the capacitors in the power supply are enormous! I unplugged the unit last night and it failed to notice for the better part of a minute...continuing to power the wireless receiver, and the panel lights remained fully illuminated. Turning the power switch off makes no difference, it still takes a long time for the caps to discharge. I'm not sure what "standby" does, other than as some camera flashes do, perhaps trickle charge the capacitors with limited supply to reduce the startup time. This is more of a curiosity than anything, but notable.

• The sub doesn't really move around when its playing. I was worried that it might "dance", but the dual opposing active drivers cancel the motion. And it doesn't seem to need isolation feet, as it has rubber feet already attached. Might want spikes for a carpet, I haven't investigated that.

• The convenience USB-A outlet on the back of the unit can power the SoundPath receiver. This is a nice feature that saves unnecessary additional cords to the wall. But the port is flimsy. So flimsy that the connection can work its way loose when the sub is doing the job it is supposed to do. The SoundPath kit comes with two USB power adapters, so you don't have to use the USB port on the sub. It doesn't pass signal, only power.

• The SoundPath wireless has a blue LED on it that was specified by someone with an E.T. complex (or that loves blue light) or else wanted to save the cost of a current limiting resistor (about US$0.01 as I write this). It used to be that you had to provide 20mA of current to get any light out of an LED. But that hasn't been true for a very long time. I had a look inside the SoundPath box and found they are driving the LED (on a stalk) directly from a port on the microprocessor/DSP. So the full ~3.2V with no current limiting resistor when this thing would likely light up nicely bright at 2.4Vf, drawing a couple of mA. Why! Oh Why! does every LED on every appliance now have to be visible from space! @#$% I glued two layers of paper over the top of the LEDs and they are now visible only when I go over and look at them, but no longer a focus of attention, and no longer visible from the street.

 

[cheungliu]

Coincidentally, I bought the Evo 150 and SVS 3000 Micro recently. I've just finished configuring the SVS 3000 Micro and equalizing it using REW and thought I'd post some notes.

The SVS 3000 Micro (just SVS from here on) manual says, when using LFE input on the plate amp, the low-pass filter is not used. And in fact, the SVS app does not allow the SVS crossover to be configured, if the LFE input is enabled.

An Dolby Digital LFE (low-frequency effects) source channel has a particular specification that the input signal is band limited to 120 Hz and is boosted relative to any single main channel speaker (in a Dolby Digital movie theater or home theater setup)...

https://www.dolby.com/uploadedFiles/Assets/US/Doc/Professional/38_LFE.pdf

:

:


Oddly, Cambridge Audio provides no bass management configuration for the Evo in the StreamMagic app and there are no settings on the front panel of this device. The only TV related setting is to allow the TV to command the Evo to wake from standby. The Evo sub out connector is lavender in color, implying that it follows the THX specification for LFE. But I wonder, and the manual is completely silent on this subject.

View attachment 165709

So if I choose a HDMI ARC input, I would expect the LFE channel to be combined in some undocumented way with the other channels in the TV audio source and presented to the Sub-Out connector. And if I choose a two-channel source (like Roon, CD, or LP), I would expect the sub-out to produce a signal sum of the two main channels, band limited at some undocumented rate and with an undocumented crossover point.

Without in-built bass management, and with only a Dickensian sliver of documentation for this $3,000 product, we are left to either guess or measure.

I placed the sub in a "double corner" (45 degrees to the corner of a column that sits in one corner of the living area). In this position, the two 8" active drivers fire at angles to the side and front walls of the room and it sits about 2' from each of the two corners on sides of the column.

I'm using SVS SoundPath wireless subwoofer kit, a pair of transmitter and receiver units. The SoundPath can accept and pass a full-range stereo signal, without compression, and with very low latency. For simplicity, I've connected the Evo lavender Sub-Out connector to a single channel of the SoundPath transmitter, using the provided mono RCA-TRS connector. I have no idea which channel is being used, and it doesn't matter. I've then connected the SoundPath receiver to the SVS using the matching TRS-RCA mono cable, and I've jacked it into the LFE input on the SVS and activated LFE mode in the SVS app, which disables the manual crossover adjustment.

I used REW to qualify the full-range signal that I fed via AirPlay2 to the Evo and measured with the UMIK-1. I manually set the gain in the SVS using the iOS app to roughly blend with the main speakers (Monitor Audio CS-180 in-ceiling speakers, two on the left channel, and two on the right, using the Evo's "A" binding posts).


The little SVS 3000 is a monster! At the default gain setting of -10db, it was way too loud! The living room is 18' x 30', open on two sides and this little sub is more than adequate. Balanced gain across the spectrum came at about -25db (set in the SVS app). The SVS has three band PEQ in-built to the plate amp. So I want to use REW to select the filter coefficients.

First, I did a quick measure and see the SVS response rolling off at 200 Hz.

View attachment 165722

So this Evo Sub-Out is not LFE, when playing a two-channel source, but rather a sum of the left and right channels. I can't tell from this whether the band limiting is in the SVS or in the Evo (or likely in both). (Perhaps someone with both an Evo and an Audio Precision instrument can determine what's coming out of the Evo Sub-Out port for 2-channel and Dolby ARC signals.)

So there are a few nodes and a couple of modes to tackle, but otherwise, not bad!

I set the target to the lower edge of the measured response line, with the room curve I've been using. I opened REW's EQ panel and unchecked all but 5 of the filters and then ran the Match Response to Target. When looking again at the EQ panel, I selected the three best adjustments and turned off the others. Then ran the Optimize gains and Q's. And experimented with iterating these optimizations (not the same results each time!)


View attachment 165732
View attachment 165731

I got a nice prediction in the end, and loaded the coefficients of the three selected bands into the SVS app PEQ settings page. Here's an example of the first PEQ loaded into the app:

View attachment 165734

Then with the SVS configured, I re-ran a full-speaker, full-range measure and generated a correction filter. This I loaded into Roon.

View attachment 165735

Up to 10K, this is good. I had to make one manual gesture in the EQ settings. I applied a High Shelf at 2K to bring up the treble response. My listening position is within the matrix of ceiling speakers. The speakers have aimable tweeters, but they only pivot so far. It is not possible to get a better treble response without standing under the speaker! Given this is a living room, not a home theater, I have limited options for what I can bring into the room.

So with Roon providing the convolution (and with a few db of headroom protection) it sounds very good! Even with the lack of high-frequency response within this listening area, the sound is very musical with the dampening of treble more a function of the room and listening position.

The SVS brings deep bass extension that I've never experienced in the living room before. It is not boomy, just tight and reactive. Acoustic bass tracks are just remarkable. Brian Bromberg "Wood" is a reference here. Hand plucked 300-year old upright double bass. I also listened to Tchaikovsky's Nutcracker Suite (given the opening of holiday season is upon us), and at elevated listening volume the bass never overpowers, and the Evo never sounds "dangerous". Sonically lovely.

I'm very grateful to this community for your sharing of experience. I hope this description of my first attempt at subwoofer equalization and room correction is somewhat helpful. This is a work in progress and I expect I'll do this all over again when I learn more. And I'd be grateful for any impressions the community has or suggestions (other than to move my furniture to restore the treble!)


Some impressions of the SVS:

• The plate amp is a monster: 800 watts RMS class-D. All that power comes from a switching power supply in-built to the unit. And it makes audible noise even at idle. It's like an old PC power supply, if you get up close to it. (In my case that would mean crawling under the piano, something I'm not going to do very often.) But be aware. If you put this thing in a bedroom corner with a hardwood floor, you'd likely hear it sparkling along during the night. It does this even on "standby." Might be worth a conversation with SVS support as to whether this is normal.
• And the capacitors in the power supply are enormous! I unplugged the unit last night and it failed to notice for the better part of a minute...continuing to power the wireless receiver, and the panel lights remained fully illuminated. Turning the power switch off makes no difference, it still takes a long time for the caps to discharge. I'm not sure what "standby" does, other than as some camera flashes do, perhaps trickle charge the capacitors with limited supply to reduce the startup time. This is more of a curiosity than anything, but notable.

• The sub doesn't really move around when its playing. I was worried that it might "dance", but the dual opposing active drivers cancel the motion. And it doesn't seem to need isolation feet, as it has rubber feet already attached. Might want spikes for a carpet, I haven't investigated that.

• The convenience USB-A outlet on the back of the unit can power the SoundPath receiver. This is a nice feature that saves unnecessary additional cords to the wall. But the port is flimsy. So flimsy that the connection can work its way loose when the sub is doing the job it is supposed to do. The SoundPath kit comes with two USB power adapters, so you don't have to use the USB port on the sub. It doesn't pass signal, only power.

• The SoundPath wireless has a blue LED on it that was specified by someone with an E.T. complex (or that loves blue light) or else wanted to save the cost of a current limiting resistor (about US$0.01 as I write this). It used to be that you had to provide 20mA of current to get any light out of an LED. But that hasn't been true for a very long time. I had a look inside the SoundPath box and found they are driving the LED (on a stalk) directly from a port on the microprocessor/DSP. So the full ~3.2V with no current limiting resistor when this thing would likely light up nicely bright at 2.4Vf, drawing a couple of mA. Why! Oh Why! does every LED on every appliance now have to be visible from space! @#$% I glued two layers of paper over the top of the LEDs and they are now visible only when I go over and look at them, but no longer a focus of attention, and no longer visible from the street.

Hi I just got my evo 150 and i had my sub svs 1000 pro. In order to activate the svs sb 1000 pro, what setting should I be using in the svs/evo 150 side?

 

[Dulcow]

Hi there,

I'm using a Subwoofer on my EVO 150 (SVS SB-1000 Pro) and I'm trying to think about how the following setup could work:

- Denon X4700H: Subwoofer 1 output to left line-level input on the SB-1000 Pro
- Cambridge EVO 150: Subwoofer output to the right line-level on the SB-1000 Pro

I would use the pre-out front from the Denon AVR to the EVO 150 auxiliary input with HT bypass enabled. I don't have the Denon yet but I tried this morning with an analogue source on the auxiliary input and the subwoofer still works...

This is going to be an issue because while watching movies, my subwoofer will get 2 signals which aren't going to be the same (likely slightly offset by electronics).

The only option I see to get my 2.1 system coexists with 5.1.2 is to add a switching box for the subwoofer inputs meaning I will have to commute it manually each time I want to listen/watch.

Any ideas how I can sort this problem out?

Thanks,

D.

 

[RiverDeep]

Hi folks.

Looking for some setup advice please.

I have:
Cambridge Audio Evo150
Kef LS50 Metas (not wireless)
Kef KC62 Subwoofer (new purchase).

How best to connect these three up?

Step 1:
Getting the audio from the Evo into the KC62 would appear to be a choice of:
1. Subwoofer out (single cable into the KC62 LFE input)
2. Pre-amp out (pair of RCA into the LFE and Sound Connect labelled inputs)

Step 2:
KC62 settings - LFE or Manual? The crossover only works for Manual, right?

Step 3:
HPF / sending the audio out to the Evo - I can't see a way to make this part of the loop work. There's an Aux input / source on the Evo, but I can't select Tidal Connect and Aux simultaneously. Anyway, help with Steps 1 & 2 - how to get the best sound into the sub is what I'm really asking. Thanks in advance.

 

[soundaholic]

Hi folks.

Looking for some setup advice please.

I have:
Cambridge Audio Evo150
Kef LS50 Metas (not wireless)
Kef KC62 Subwoofer (new purchase).

How best to connect these three up?

Step 1:
Getting the audio from the Evo into the KC62 would appear to be a choice of:
1. Subwoofer out (single cable into the KC62 LFE input)
2. Pre-amp out (pair of RCA into the LFE and Sound Connect labelled inputs)

Step 2:
KC62 settings - LFE or Manual? The crossover only works for Manual, right?

Step 3:
HPF / sending the audio out to the Evo - I can't see a way to make this part of the loop work. There's an Aux input / source on the Evo, but I can't select Tidal Connect and Aux simultaneously. Anyway, help with Steps 1 & 2 - how to get the best sound into the sub is what I'm really asking. Thanks in advance.

Hey, just ran into your post. How did you solve it in the end?
I also have the LS50 Metas and the KC62 and am looking for a new amp to power them. Was wondering exactly the same in terms of how I would set them up with the CA Evo 150, since that is one potential choice.
Thanks and cheers