Biamping help and opinions

[anirudhchandrashekar]

Hi all. Just wanted to know the optimum way to bi-amp speakers.

Had this signal chain in mind - DAC -> Analog in of an Integrated amp. The binding posts of the IA will drive LF of speakers and preouts from the IA will connect to a pro amp (with gain control) needed for the headroom and LF.

Would a biamping scenario like this be feasible? Has anyone tried biamping in this way? Looking for your valued opinions on the same.

Regards.

 

[ravikumar-rotel]

Its advisable to use the IA's pre out to connect to a good stereo amplifier meeting your speakers power requirements. If your IA has 2 pre outs(which is a rare thing) then connecting each pre outs to two different stereo power amps(preferably mono blocks) to drive your speakers which actually qualifies for a true bi amping. Your idea of a Daisy chain connectivity will not provide you desired results due to gain mismatch and synergy completed gone.

 

[anirudhchandrashekar]

Had another question: Is it compulsory to use a filter or an active EQ before sending power to the tweeters? Will sending the full range signal blow the HF unit?

 

[ravikumar-rotel]

I dont know what you mean by filters..

Speakers have crossovers built in which does this of splitting the right frequencies to the drivers. The crossovers in Speakers is also one of the factors affecting the cost of the speakers.. that is why some speakers are very very expensive.
When are you are bi-amping, you normally remove the links connecting the HF & LF on the binding posts to send seperate power to HF and LF either through two stereo power amps or through mono-blocks, the latter being the best and ultimate for stereo.

 

[ravikumar-rotel]

Its advisable to use the IA's pre out to connect to a good stereo amplifier meeting your speakers power requirements. If your IA has 2 pre outs(which is a rare thing) then connecting each pre outs to two different stereo power amps(preferably mono blocks) to drive your speakers which actually qualifies for a true bi amping. Your idea of a Daisy chain connectivity will not provide you desired results due to gain mismatch and synergy completed gone.

The daisy chain method may also affect imaging and sound staging due to the nature of signal separation

 

[ravikumar-rotel]

your PSB Synchrony One with a 4 OHM impedance and 300 watts power is a hard to drive speakers which seriously needs clean power from a good power amp or mono blocks to get the complete potential of those speakers. And it also needs the right paring, which can blend with its character.. a very good power amp is what you need, NOT ATI, emotiva or anything in that league. 300 watts actually needs a big room with right acoustics.
in my opinion an integrated amp wont be the right choice for those speakers. if you overdrove those speakers with your integrated amp, you will end up smoking those tweeters due to clipping.. Over-powered AMP/s with a headroom of atleast 50% more power is what i prefer in my setups.

 

[newlash09]

Hi all. Just wanted to know the optimum way to bi-amp speakers.

Had this signal chain in mind - DAC -> Analog in of an Integrated amp. The binding posts of the IA will drive LF of speakers and preouts from the IA will connect to a pro amp (with gain control) needed for the headroom and LF.

Would a biamping scenario like this be feasible? Has anyone tried biamping in this way? Looking for your valued opinions on the same.

Regards.

Hi Anirudh...there are lots of ways to do it. First is active or passive. Active is the best. But is complex. In this you will be removing the cross overs and driving the drivers direct with the power amps. Passive won't really give you any gains, unless your present amp is under powered for the speakers. So you will be in effect be adding more power to them.. However if your present amp is up to the job, Iam afraid you might not find the required benefits.

However if you do intend to go down this route, then you ideally need a second IA amp of the same model to drive different drivers. Then there is vertical and horizontal bi amping to consider. So lots of ways to skin a cat here.

However if you are considering to add a pro power amp. Then I would suggest adding it to the bass driver. But then the proamp has to have the exact gain of the power amp section of your IA, or you will have frequency imbalance leading to a complete bass over load or under loading.

If you can't find a pro power amp with the same gain as your IA, then you will need to add a external preamp to the control the volume of the power amp

So all in all, it's complex. And your best and easier way is to get another IA amp of the exact same model you presently have. Trying to mate 2 different amps with different gains requires a lot more kit. Iam planning for active triamping soon. But it will be a very complex and long chain. I can share here if you are interested. But I can assure it, Iam only doing it out of boredom, and no one in their right mind should go down this route. There better ways to get good music more easily.

 

[newlash09]

Had another question: Is it compulsory to use a filter or an active EQ before sending power to the tweeters? Will sending the full range signal blow the HF unit?

As long as you don't remove the crossover inside the speaker, then there is absolutely no harm in feeding a full signal to tweeters binding posts. The crossover will filter out the rest of the frequency range , only letting the required high frequencies reach the tweeter. But it is a huge loss of power. Tweeters never need more than a few measly watts. With 20W being max for most of them without blowing. So it would be a big waste of power trying to feed the tweeters with a dedicated amp. By the way..Iam curious to know what you are trying to achieve here. In my case Iam going biamped as I want to run tubes for mids and highs. And solid state class A for bass.

My chain is a dac > preamp > eternal analogue crossover with gain and phase adjustment > power amps > drivers.

The key component in the above chain is the analogue crossover. I will be equalizing the different gains of the SS amps and tubes with its inbuilt gain control. So that I can achieve the same balance when I increase or decrease the volume via the preamp. So having a single volume control is essential , as we don't want to be adjusting multiple volume controls every time. To achieve that balance without a this analogue crossover, id need to have all the amps of the same type. Fondly hope you get my drift. All the best

 

[anirudhchandrashekar]

@newlash09 Thanks a lot for the detailed insight, appreciate it. Well, my speakers which are the PSBs are notorious to dip down to 2.6 ohms at LF. So needing the headroom for this, was my first goal. Since, the room treatment is going on and the absorption limit of the room is higher, I tend to push the setup to almost reference levels. And in doing so, the speakers demand an ample amount of current.

So, I decided to head towards the Pro amp route and I am driving them fullrange with Crowns currently. I am still evaluating the amp, tbh! Fortunately for me, it does come with a gain control or an input attenuator which helps to control the volume in case it is biamped and another amp is added to drive a section of the speakers.

My original intent here was to use either tubes or an IA to drive the highs while letting the proamp drive LF and give me the ample headroom that's required. Since it's just an experiment, I want to try it out to sate my curiosity, haha!

 

[newlash09]

@newlash09 Thanks a lot for the detailed insight, appreciate it. Well, my speakers which are the PSBs are notorious to dip down to 2.6 ohms at LF. So needing the headroom for this, was my first goal. Since, the room treatment is going on and the absorption limit of the room is higher, I tend to push the setup to almost reference levels. And in doing so, the speakers demand an ample amount of current.

So, I decided to head towards the Pro amp route and I am driving them fullrange with Crowns currently. I am still evaluating the amp, tbh! Fortunately for me, it does come with a gain control or an input attenuator which helps to control the volume in case it is biamped and another amp is added to drive a section of the speakers.

My original intent here was to use either tubes or an IA to drive the highs while letting the proamp drive LF and give me the ample headroom that's required. Since it's just an experiment, I want to try it out to sate my curiosity, haha!

Thanks for the reply Anirudh...we both seem to be in the same boat

Iam doing exactly the same thing right now. Tubes for mids and highs. And SS for bass. But as I mentioned I have a external analogue crossover to compensate for the different gains of both the amps. Even though the tube amps have gain switches on them to adjust same directly. But to get maximum efficiency out of my amps, especially tube amps, I will be using the external crossover to cut off bass frequencies from the tube amps, and cut off mid and high frequencies from the SS amp running the bass. This is more important for the tube amps, as bass is very demanding and don't want them to get strained running full range.

Since the crown has a attenuation switch to balance it's gain to what ever tube or IA amp you get. I think you are on the right track.

But I have friends running power hungry speakers with crowns and they are very happy with the sound. And they have tried some expensive amplification too. So I feel you have a second option here. How about adding a tube pre amp and an additional crown power amp. So you can use both the crowns for biamping, and a tube pre will give you the tube magic as well.

One of my friends was very happy driving his Maggie's with a crown power amp, and my tube dac cum preamp. He was running SS preamp before. But he felt the sound a bit edgy at times. Adding that tube preamp cum dac, seems to have smoothened the sound out for him. So he is very happy with a tube preamp, driving crown power amps now. So maybe worth a try. All the best

 

[anirudhchandrashekar]

Hey guys. Slight update. Tried biamping the PSBs with a Class AB power amp and my Crown XLS2502.

The AB amp was driving the HFs and the Crown was handling the LFs. My chain was like this:

DAC -> Preamp Controller (Onkyo AVR) -> Tube Buffer -> RCA Y Splitter cable -> Taking signals to Two Power Amps -> Speakers.

I could get the setup to work but the mid bass was very muddy and the bass became very loose even though it was the same Crown which was driving it (It is very very tight when Crown drives the speakers full range)

So, this is how the speaker measured when John Atkinson reviewed it on Stereophile back in the day. Since the Crown comes built-in with DSP which involves LPF, HPF and BPF (Pass Filters), I was wondering at what frequency to set the LPF on the Crown so it just drives LF and not worry about HF.

As per spec, the crossover from the bass drivers to the midrange should be around 500Hz, but with LPF set at this frequency, it took away some of the essence from the mid bass. So I bumped it up to 600 and was playing around in steps of 30Hz, couldn't get it to work. Can someone look at the graph below and suggest a crossover frequency?


Or I assume, it was just plain gain mismatch but the Crown has input attenuators and I was playing around with it, no fruition however.

Can someone help me why this is the case? Is it because the Crown is a class D and the other amp is a class AB? I am a neophyte when it comes to biamping and I would love some insight. I was also reading about using an AC voltmeter to measure gains from both amps or something of that sort.

My intention to biamp is to see if I can repurpose the Crowns for LF to give me the headroom I need while a sweeter sounding class AB to give me good HFs. With this arrangement I am hoping to not spend a lot on a high current class AB for now. If the biamp route does not work, I will however look into a beefier AB amp however. FM @dheerajin runs his chain in a biamp setup, I would love some clarity on this.

Cheers!

 

[newlash09]

Hey guys. Slight update. Tried biamping the PSBs with a Class AB power amp and my Crown XLS2502.

The AB amp was driving the HFs and the Crown was handling the LFs. My chain was like this:

DAC -> Preamp Controller (Onkyo AVR) -> Tube Buffer -> RCA Y Splitter cable -> Taking signals to Two Power Amps -> Speakers.

I could get the setup to work but the mid bass was very muddy and the bass became very loose even though it was the same Crown which was driving it (It is very very tight when Crown drives the speakers full range)

So, this is how the speaker measured when John Atkinson reviewed it on Stereophile back in the day. Since the Crown comes built-in with DSP which involves LPF, HPF and BPF (Pass Filters), I was wondering at what frequency to set the LPF on the Crown so it just drives LF and not worry about HF.

As per spec, the crossover from the bass drivers to the midrange should be around 500Hz, but with LPF set at this frequency, it took away some of the essence from the mid bass. So I bumped it up to 600 and was playing around in steps of 30Hz, couldn't get it to work. Can someone look at the graph below and suggest a crossover frequency?
View attachment 37876

Or I assume, it was just plain gain mismatch but the Crown has input attenuators and I was playing around with it, no fruition however.

Can someone help me why this is the case? Is it because the Crown is a class D and the other amp is a class AB? I am a neophyte when it comes to biamping and I would love some insight. I was also reading about using an AC voltmeter to measure gains from both amps or something of that sort.

My intention to biamp is to see if I can repurpose the Crowns for LF to give me the headroom I need while a sweeter sounding class AB to give me good HFs. With this arrangement I am hoping to not spend a lot on a high current class AB for now. If the biamp route does not work, I will however look into a beefier AB amp however. FM @dheerajin runs his chain in a biamp setup, I would love some clarity on this.

Cheers!

Hi again anirudh...Will be difficult to suggest a crossover without knowing the type of cross over being employed and most importantly it's slope. Can you find the slope of the crossover on the crown. And then again in your speakers.

Did you try driving with that tube preamp before in full range and were you still getting that loose bass.

Please see my reply yesterday regarding cross overs and slopes in this thread.

How a 3 way speaker's woofers behave when it is configured as "Small" for a 5.1 HT system?

Let us assume a Speaker of following: Speaker: 3 way 4 drivers : 1 tweeter + 3 woofers Frequency Response: 42Hz to 35KHz Crossover Frequency: 90Hz/2.2KHz In above example, given two crossover frequencies (90Hz and 2.2KHz) and 3 woofers in a typical stereo setup: It is my understanding that...

www.hifivision.com

 

[tuff]

Have you tried without setting the crossover in the crown amplifier? Try running it full range. If the speakers are bi-amp capable, it already should block the high frequencies from the woofer.

 

[MaSh]

I second tuff. The speakers have a built in crossover. Let that decide what's best for the drivers. Run your amps full range.

Also, try running some other amp instead of the tube buffer. Is there any other way you can run the two amps without using a Y cable? A pre with two preouts?

MaSh