Bryston 10B Sub and Crossovers Generally

[VT Skier]

Hi James,

I'm debating whether to buy your 10B or a passive crossover or to use no crossover at all. I have Dynaudio Sapphires, and I've just ordered a JL Audio F112 to supplement the bottom end of the Dyns.

Can you (or anyone else here with knowledge on this subject) give me an idea of what I might gain by adding your crossover vs. a passive (like a Marchand) vs. just using the controls on the sub to supplement, or have the sub handle completely, the sound from approximately 80Hz on down to the bottom?

Having poked around a bit on the internet, most people seem to use just the sub's controls, few people seem to use a passive, and a very few seem to use an active crossover. For example, I know Ivan uses subs to supplement his Strads, but it seems (by looking at his signature, although I could be wrong) he's not using an external crossover at all.

Thank you

Jon

[James Tanner - Bryston]

Originally Posted by VT Skier

Hi James,

I'm debating whether to buy your 10B or a passive crossover or to use no crossover at all. I have Dynaudio Sapphires, and I've just ordered a JL Audio F112 to supplement the bottom end of the Dyns.

Can you (or anyone else here with knowledge on this subject) give me an idea of what I might gain by adding your crossover vs. a passive (like a Marchand) vs. just using the controls on the sub to supplement, or have the sub handle completely, the sound from approximately 80Hz on down to the bottom?

Having poked around a bit on the internet, most people seem to use just the sub's controls, few people seem to use a passive, and a very few seem to use an active crossover. For example, I know Ivan uses subs to supplement his Strads, but it seems (by looking at his signature, although I could be wrong) he's not using an external crossover at all.

Thank you

Jon

Hi Jon

I would say the main advantage of an Active crossover is flexibility. Using a Passive is fine if the sub and mains and crossover is designed together - example would be the Thiel products where they have a dedicated passive crossover designed for their speakers.

A lot of people though just use the controls on the added Sub as in most cases it will be sufficient if you are just augmenting the main speakers and running the Mains full range. If the Mains are small it is nice to reduce the bass load on them as it usually allows for better mids.

With a dedicated electronic crossover you have the flexibility of choosing exactly where the crossover point will be between the Mains and the Sub as well as the Slope (roll off) on both speakers. Most built in crossovers in Subs only provide one slope.

Integrating a Sub into a system is not an easy task if you want it to be seamless so being able to adjust both crossover point and slope on both the Hipass and the Lowpass sections provides much more flexibility in getting the phase angle correct at the crossover point. This is much more important in a Stereo setup I think than a Surround setup where you are just adding the .1 channel.

Hope this helps.

[jdandy]

Originally Posted by VT Skier

Hi James,

I'm debating whether to buy your 10B or a passive crossover or to use no crossover at all. I have Dynaudio Sapphires, and I've just ordered a JL Audio F112 to supplement the bottom end of the Dyns.

Can you (or anyone else here with knowledge on this subject) give me an idea of what I might gain by adding your crossover vs. a passive (like a Marchand) vs. just using the controls on the sub to supplement, or have the sub handle completely, the sound from approximately 80Hz on down to the bottom?

Having poked around a bit on the internet, most people seem to use just the sub's controls, few people seem to use a passive, and a very few seem to use an active crossover. For example, I know Ivan uses subs to supplement his Strads, but it seems (by looking at his signature, although I could be wrong) he's not using an external crossover at all.

Jon.......When I owned a pair of Sonus Faber Guarneri Memento speakers I used the Bryston 10B Sub active crossover to great advantage. The Memento's began to roll off below about 48Hz, and by 40Hz the low frequency output was almost nonexistent. I used two McIntosh XLS112 powered subwoofers to fill the bottom octave. By using the 10B Sub active crossover I was able to remove the low frequencies from the Mementos and send these lower frequencies only to the subs. After much experimentation, which the Bryston 10B Sub allows, I settled on a 70Hz crossover for both High Pass and Low Pass, with an 18dB per octave roll-off. I used the level controls on the XLS112 subs and kept the 10B Sub High Pass level control set at Unity Gain. This was a match made in heaven, and the Guarneri Memento's lower midrange performance gained greater definition and improved dynamics.

The Bryston 10B Sub is an excellent active crossover. It is extremely neutral, and absolutely silent. Once it is installed, dialed in and performing its intended function it simply disappears. I can recommend the Bryston 10B Sub active crossover without reservation. It is an excellent audio component. My review is here: http://www.audioaficionado.org/bryst...io-system.html



Photo from 6moons.com

[PHC1]

As did I whith the same speakers, JL F112 and also a Bryston 10B. Similar to Dan's setup, I settled on 75Hz on down going to the subs. Excellent results!

[VT Skier]

Thank you all for your help. Do you determine the settings solely by listening or do you use microphones, measuring software and test tones?

I know the Sapphires have a first-order crossover, and looking at the measurements in Stereophile they seem to measure flat to about 50Hz, so I assume I should crossover to the sub a little below or above that point, but I'm not sure what slope would be best or what the other settings should be.

Trial and error?

[jdandy]

Originally Posted by VT Skier

Thank you all for your help. Do you determine the settings solely by listening or do you use microphones, measuring software and test tones?

I know the Sapphires have a first-order crossover, and looking at the measurements in Stereophile they seem to measure flat to about 50Hz, so I assume I should crossover to the sub a little below or above that point, but I'm not sure what slope would be best or what the other settings should be.

Trial and error?

Jon.......The 10B Sub allows you to select and test a wide range of settings, and it is great fun to adjust the settings and listen. Often the differences between on point and another are subtle, so it is wise to make selections, then spend a few hours or more listening before making any new changes. I wouldn't term the process Trial and Error, more like Select, Listen, Decide.

A first order crossover means your speaker designer chose a 4dB slope at the crossover point. This means at the selected crossover point both the high pass and low pass frequencies blend above and below the selected crossover point to a much greater degree than at 12dB or the steeper 18dB slope. I prefer not to have my low frequencies extended into the next drivers range at a 4dB per octave slope. I roll off the low frequencies at 18dB per octave. That is one of the joys of the Bryston 10B Sub. You have many options, and can decide for yourself what works best with your speakers.

With respect to the 50Hz measurement you made reference to, I would go above that point, crossing over to the subwoofer at 60HZ. This ensures a smoother and more accurate response from your speaker's low frequency driver, and frees the amplifier from having to power 60Hz and below. Again, this is my opinion, and your final settings will be determined by your own tests. The beauty of the 10B Sub is that nothing is cast in stone, and you can make changes at any moment you desire.

[VT Skier]

Thanks again for all the helpful advice. I understand JL is coming out with an external crossover so I think I'll wait to compare the two before committing to either.

I'll come back and post about results once I've put a crossover in my system. In the meantime, I've got the F112 on the way and I'll use the sub's controls to integrate it around 80Hz or 90Hz.

[PHC1]

Originally Posted by VT Skier

Thanks again for all the helpful advice. I understand JL is coming out with an external crossover so I think I'll wait to compare the two before committing to either.

I'll come back and post about results once I've put a crossover in my system. In the meantime, I've got the F112 on the way and I'll use the sub's controls to integrate it around 80Hz or 90Hz.

If you are not using the external crossover just yet, I think you'll find it easier to try to blend the sub starting really low and trying to augment the speakers where the bass starts to roll off. Get an SPL meter to check your progress and fine tune to your preference and liking from there by ear.

[VT Skier]

I'll give that a try next week, when the sub arrives. Would it best to avoid using JL's built-in equalizer and do it all by ear? Or would I use the equalizer and then do some fine tuning?

[t0tor0]

hi all,

i am also looking at getting a 10B. However, I am deciding between the SUB and STD version.

i understand that the difference is in the range of crossover points settings. (SUB from 40Hz - 500Hz and STD from 70Hz - 4.5kHz). but it seems that almost everyone is setting the cutoff between 80hz - 120hz. in this sense, wouldn't it be better to have a STD version. this will also have a flexibility in doing a 3-way crossover by adding another 10B-STD should one decide to go into bi-amping the speakers' mids and highs + sub in the future?

i am assuming that the SUB model might be more for adding a sub to complement floor-standing speakers which can go very low. for complementing bookshelves, STD should be sufficient?

anyway, what i really want to ask: is there any difference is quality between the SUB and STD version if i intend to set the cutoff frequency between 80 - 120?