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View Full Version : Bryston 10B L-R and JBL 4350 translation



neanderthal
08-15-2008, 03:37 PM
I finally received the Bryston 10B L-R and I gave bryston the serial number and this is what they said about it, ("Its a special Quintesence unit which is set-up with +12dB @ 22.5Hz boost with a 150Hz crossover point.."). The 4350 crossover points if I remember correctly without looking are 250Hz , 1.1KHz and 9KHz.
I know instead of 150Hz I need 250Hz but whats up with the +12dB @ 22.5Hz boost? I really don't think I need the 22.5Hz boost either and the +12db means what?
I also already know Iam going to probably send this back to Bryston to have whatever it needs done, I just think I need to have some general knowledge about what's going on with it.
Maybe a basic electronic coarse is in order. I really don't like to bend everyone's ear about the simplest things I should already know if Iam going to be messing with this stuff but Iam already into this with both feet and need bailed out alittle....well OK alot.
I just don't want to screw up the 4350's and have to redo something a second time out of ignorance. Thanks for any enlightenment on this you can provide for a simple mind.

4313B
08-15-2008, 04:25 PM
whats up with the +12dB @ 22.5Hz boost?Probably some subwoofer EQ. You don't need it.

You might want to send a PM to Bo asking him about his Bryston.

DAVID POHLER
08-16-2008, 04:05 PM
Your new Bryston uses cards to set the low/high pass settings. Go to Brystons web site to download the manual. This is a very nice unit, You'll enjoy it when it's up and running. I currently use the 10B standard, I'd love to try the 10B-LR.

Dave

boputnam
08-18-2008, 11:03 AM
...whats up with the +12dB @ 22.5Hz boost? .4313B's got it.


Probably some subwoofer EQ. You don't need it....and likely don't want it!

My grab on "straightforward" active crossovers is, you want them to merely be a crossover, with no imbedded fllters. That is, they should be able to move from one application to another and fit equally well (so long as the same crossover point is employed). Brystons and others like them are very good solutions for installations where the speakers are not changing. This is in contrast to DSP's which marry all manner of system control - everything can be modified.


You might want to send a PM to Bo asking him about his Bryston.Send an email to James Tanner (jamestanner@bryston.ca) with the info you've received and inquire about resetting the crossover point and removing that bass filter. Since it's likely going to have to go back to Peterborough, you'll need an RA - and, they can help you with shipping info to avoid duty (since it's repair/service).

Andyoz
08-18-2008, 12:34 PM
12dB boost at 22.5Hz sounds a bit insanne to me. That must really suck the power out of the system at the higher bass frequencies that really matter, i.e. above 40Hz.

Bo, why would anyone want that?

neanderthal
08-18-2008, 05:35 PM
4313B's got it.

...and likely don't want it!

My grab on "straightforward" active crossovers is, you want them to merely be a crossover, with no imbedded fllters. That is, they should be able to move from one application to another and fit equally well (so long as the same crossover point is employed). Brystons and others like them are very good solutions for installations where the speakers are not changing. This is in contrast to DSP's which marry all manner of system control - everything can be modified.

Send an email to James Tanner (jamestanner@bryston.ca) with the info you've received and inquire about resetting the crossover point and removing that bass filter. Since it's likely going to have to go back to Peterborough, you'll need an RA - and, they can help you with shipping info to avoid duty (since it's repair/service).


Thanks for the info Bo. The email is sent so I'll wait to hear back from James.

boputnam
08-18-2008, 07:15 PM
12dB boost at 22.5Hz sounds a bit insane to me. That must really suck the power out of the system at the higher bass frequencies that really matter, i.e. above 40Hz.

Bo, why would anyone want that?Andy, I have no idea. Plus, it's damned hard for a speaker to produce without support from proper cabinet design/tuning. I have never run across a need for that in any system I tune, but truthfully, measurements that low are far from reliable anyway.

It's specific to 0.5 Hz. Somebody's making stuff up.... :blah:

Mr. Widget
08-18-2008, 11:50 PM
It's specific to 0.5 Hz. Somebody's making stuff up.... :blah:If the system has the electrical headroom (watts) along with the requisite thermal and mechanical headroom (a robust driver with enough Xmax) it can make perfect sense in the right enclosure.

The 10B had obviously been set up as a sub crossover.


Widget

neanderthal
08-19-2008, 03:04 PM
Here is the answer I received from the email I first sent to Bryston service USA and not James Tanner. Hopefully James Tanner will have better news. Atleast my bad luck is consistent and not sporadic.At this point it looks as though this one is down the road pending on what james has to say about modifying it.

Bryston Service USA (usaser@bryston.ca)Sent:Tue 8/19/08 2:55

Unfortunately this is an early Quintessence 10B specially built for a
particular application and cannot easily be modified. It is our advice to
look for a standard 10b crossover.

boputnam
08-19-2008, 05:20 PM
I would encourage you to get through to Tanner. Bryston are very proud of their products and look after users pretty well. They can certainly modify that unit, removing the +12dB "bump" filter and change the crossover point, and whatever else, but it will cost. Get an estimate.

At least, call Peterborough and get some tech on the phone. I have emails from at-least four in their organization - they have been very responsive.

Having a Bryston modified far outweighs reverting to any of the alternative product available out there.

neanderthal
08-19-2008, 06:33 PM
I would encourage you to get through to Tanner. Bryston are very proud of their products and look after users pretty well. They can certainly modify that unit, removing the +12dB "bump" filter and change the crossover point, and whatever else, but it will cost. Get an estimate.

At least, call Peterborough and get some tech on the phone. I have emails from at-least four in their organization - they have been very responsive.

Having a Bryston modified far outweighs reverting to any of the alternative product available out there.


Thanks for your help and your time Bo. I was going to wait and see what James Tanner says when he gets back with me before I move it. I'd really like to use it,it just suprised me that the first email I got from Bryston before I emailed Tanner was short as it was.
What I got out of it is they didn't want to mess with it. Selling it will be a last resort. I have a M552 and a M553 to fall back on but I think the bryston would be the best choice. As you suggested there will probably be some phone calls before this is a done deal and I throw the flag in.
Thanks again for your time

4313B
08-19-2008, 06:37 PM
it just suprised me that the first email I got <snip> was short as it was.

What I got out of it is they didn't want to mess with it.Exactly. The first attempt is to see if they can make you go away with minimal effort on their part. It's a common ploy with American companies. I'm not sure why Canadian companies would want to follow suit.

Ian Mackenzie
08-19-2008, 07:26 PM
It only take minimal effort

This the simplified fix for the Xover filters


Capacitors: Low pass: C1=40n, C2=20n, High Pass: C(ab)=4n7
LP HP HP LP HP HP


FREQ. Ra,Rb R1 R2
249 Hz 22K600 95K300 191K00


The manual and schematics for the unit can be down loaded.

These filters appear to be L-R so be aware the original 4350 card filters were not depending on the version see 5235 manual for details.

You will probably have to Eq the crossover region and mess with the polarity of the high pass amp to get it dead right


If Byston are so lazy (its the Canadian attitude ..trust me) then refer to a local technician. He will find the bump filter without much hastle and sort that.


The unit is too good to sell on.

Enjoy


Ian

John
08-19-2008, 08:50 PM
Exactly. The first attempt is to see if they can make you go away with minimal effort on their part. It's a common ploy with American companies. I'm not sure why Canadian companies would want to follow suit.


Bryston is Canadian, the usa contact is just that a contact. All the good stuff happens in Peterborough.:bouncy:

They did a extensive rebuild on my pair of 19 year+ 4B's under warranty. And they even picked up the return shipping:applaud:

4313B
08-20-2008, 01:56 AM
Bryston is Canadian, the usa contact is just that a contact. All the good stuff happens in Peterborough.:bouncy:

They did a extensive rebuild on my pair of 19 year+ 4B's under warranty. And they even picked up the return shipping:applaud:Ah! Ha! :)




Thanks for the post Ian.

scott fitlin
08-20-2008, 08:54 PM
Bryston is Canadian, the usa contact is just that a contact. All the good stuff happens in Peterborough.:bouncy:

They did a extensive rebuild on my pair of 19 year+ 4B's under warranty. And they even picked up the return shipping:applaud:Bryston,s 20 year warranty is incredible.

Service and tech support are 1st Class. Call Bryston you talk to PEOPLE, NOT an AUTOMATED Answering Menu. And they WILL give you EXEMPLARY SERVICE.

Bryston is the BEST at warranty, service, tech support, and custom solutions.


:bouncy:

neanderthal
08-21-2008, 03:07 PM
I sent an email to bryston,canada at cdnser@bryston.ca last night about changing the crossover point from 150Hz to 250Hz and doing away with the +12db@ 22.5Hz boost and it looks like so far it is getting farther than the last email I sent to Bryston Service USA (usaser@bryston.ca).
Atleast I feel they are going to make an effort to actually see what's involved instead of coming across as not interested and short in their response at usaser@bryston.ca .:banghead:
Today's response is below,and still never heard anything back from James Tanner yet.:banghead:
I really don't want to have to take off work to come home and call but maybe that's what it is going to take before this is a done deal.
There are alot of people saying that Bryston is second to none dealing with customers but So far this hasn't been the best of experiences.:banghead:

I'll see where the last email to them goes and go from there.
Has anyone had any first hand experience with the Pass Labs crossover?? How's Pass Labs customer service?? To everyone chiming in with advise ect. I appreciate it more than you know. The knowledge and advise you all give is priceless to me.:wave:


Hi Pete;

I am checking with the technician responsible for crossovers and will advise you on whether what you need can be done or not, and what would be involved. I hope to have an answer later today.

Thanks,

Mike Pickett
Service Manager
Bryston Ltd.
Tel. (705) 742-5325
Fax. (705) 742-0882
E-mail - mpickett@bryston.ca
URL - http://www.bryston.ca/ (http://www.bryston.ca/)

boputnam
08-22-2008, 10:05 AM
Pete...

That looks pretty promising to me. I think you'll get a reasonable quote back and be able to forge ahead.

FWIW, my 10B L-R custom jobby just returned yesterday and boy is it nice to have it back! The "interim alternative" was nice, but nothing like this. It sounds phenomenal.

I trialed it first with "Old McDonald had a farm...", 'cause it lives in the CD player (granddad, ya know... :) )((I guess I really SHOULD post that in the "What's Playing Now" thread...:p )) , but the sound begged for some Patricia Barber, and I actually had to sit my ass down and enjoy the first home listening session in many, many months. It was G-R-E-A-T.

Now, off to another weekend of gigs and festivals...

Mr. Widget
08-22-2008, 10:13 AM
I trialed it first with "Old McDonald had a farm...", 'cause it lives in the CD player (granddad, ya know... :) )((I guess I really SHOULD post that in the "What's Playing Now" thread...:p )):rotfl:



Now, off to another weekend of gigs and festivals...Damn... you never stop. :bouncy:

Hi Pete,

We always phone Mike Pickett directly and get excellent service.

Widget

neanderthal
08-22-2008, 04:44 PM
:rotfl:

Damn... you never stop. :bouncy:

Hi Pete,

We always phone Mike Pickett directly and get excellent service.

Widget


Thanks again for your time Widget , That's what I guess I'll have to do Monday as I didn't get any response again today.

boputnam
08-24-2008, 06:47 AM
:rotfl:

Damn... you never stop. :bouncy:Ha! These are "the good old days...".

Played a real shithole in Denver Friday, second night of two there. I missed the first (dayjob duties) and arrived to horror stories, so I went in early and tried to wrestle the system into a forgiving manner. The DSP was totally, totally screwed-up. First, subs were L/R (uh, why...?) and mains full-range (passive) two-ways. This should be easy, right? Well, if my memory serves, here's the crossover settings I encountered:

Sub
HPF - "0" Hz, Bessel -12dB
LPF - 78Hz, Butterworh -6dB

Mains
HPF - 120Hz, Butterworth -12dB
LPF - infinity, Bessel -12dB

:banghead:

There's tons more to this story, but that captures it pretty well...

boputnam
08-25-2008, 04:33 PM
Today using Smaart I took some measurements of my 10B, just back from being modified at Bryston. The objective was to crossover at 290Hz, Linkwitz-Riley -24dB slopes.

I tested the crossover one channel at a time. Here, I show the Left channel.
Using Smaart, I sent Pink Noise into the input and came out of each output (Low, High) back into Smaart. The results are impressive.

The cursor is a close as I could get it to the crossover point.

The two channels are IDENTICAL - when the traces from both channels are showing, you cannot see one for the other. Incredible matching of components, I'd say.

(I know the image is too wide for easy viewing, but any shrinkage degrades definition.)

Ian Mackenzie
08-25-2008, 04:52 PM
Hi Bo,

Please followup when you have it all set -up.

Ian

boputnam
08-25-2008, 04:58 PM
Hi Bo,

Please followup when you have it all set -up.

IanIt is, as we type... :applaud:

neanderthal
08-25-2008, 06:21 PM
I called Bryston today and talked to Mike Pickett which is as I understand the service manager. He said since this is a Quintessence 10B L-R (whatever that means) , it could be as he said hard wired or who knows since it is a special build.
Mike wanted me to send him some pics with the top cover off so he could see the cards which I took and sent. Not only did I send a couple pics attached to the email I sent a photobucket link with 22 pics.
Here is the two pics I sent him and the link to the photobucket account if anyone is interested in taking a gander and adding your two cents.
http://s380.photobucket.com/albums/oo249/Bryston_10B/

boputnam
08-25-2008, 08:42 PM
Show me yours, I'll show you mine... :p

Chas
08-26-2008, 11:22 AM
.

FWIW, my 10B L-R custom jobby just returned yesterday and boy is it nice to have it back! The "interim alternative" was nice, but nothing like this. It sounds phenomenal.


Bo, did you have them make a change in slopes? A curious 4345 owner wants to know.:)

boputnam
08-26-2008, 12:39 PM
Bo, did you have them make a change in slopes? A curious 4345 owner wants to know.:)Hi, Chas...

Yes, the first iteration followed the original 4345 set-up, with the Bryston in-place of the 5234A, and using -12dB slopes. It sounded excellent, but that 2nd order Butterworth filter has a +3dB bump at the crossover point. It turned out to be not optimum for my application.

After trialing a few settings on the Ashly XR1001, I found the Linkwitz-Riley -24dB slopes to be preferable - I know I prefer this in SR applications, but it also proved desirable for my home application. As 4313B has pointed out elsewhere, handling the crossover to the 2122H is very important to achieving proper tonality of this four-way. Too much overlap between the 2245H and the 2122H muddies the 2122H's contribution. Damned true. The 2122H handles a very tight band pass, but it is absolutely crucial in the accuracy of the 4345's reproduction.

So, the 10B LR now has Linkwitz-Riley -24dB slopes. You can see them for yourself - just iterate the dB change by octave on that Smaart plot.

Chas
08-27-2008, 05:25 AM
Thanks Bo. You confirm my experience since I set up mine. Fourth order works great for me, too. As a side benefit, I also think the steeper L-R slope helps protect the 2122H -experience has shown (and, the JBL data sheet, too!) that they are not as robust as say, the 2123H.

I can't read the screen shot you posted with my crappy monitor!

boputnam
08-27-2008, 01:34 PM
I can't read the screen shot you posted with my crappy monitor!To you, and anyone else interested send me an email to: me (mailto:LHTreasurer@comcast.net).

Chas
08-28-2008, 08:06 AM
To you, and anyone else interested send me an email to: me (LHTreasurer@comcast.net).

Thanks anyway Bo, but I checked last night at home, it's plenty clear there. Still working with worn out CRT based monitors at work!:(

neanderthal
08-28-2008, 02:47 PM
I got the best new today that I have heard since Rick said my 4350 cabinets are ready to pick up. Looks like Bryston is going to modify the 10b L-R after all, the email from them is below.

Hi Pete;

As far as I can tell, the modifications done to this unit are fairly simple,
and can be undone quite easily. I would suggest that the unit should come
to our Canadian manufacturing facility, so that our engineering department
can deal with any issues that may come up. The unit should ship to our US
service department, and they will forward it across the border for you.

I estimate that the modification would take approximately 1 hour @ $75.00,
plus 1 hour to change the frequency, and $50.00 for a new set of programming
boards. You will get the 8 150 Hz boards back with the completed unit. You
would also be responsible for return shipping. All told, it should be less
than $250.00 for everything. If you are having problems with one of the Low
Pass Mute switches, this would be covered by the warranty, at no charge.

If you wish us to go ahead with this, please advise your complete contact
info, including shipping address and phone #, and I will issue an RA # for
the repair.

Thanks,

Mike

boputnam
08-28-2008, 06:19 PM
(quoting...) GET 'ER DONE!! :applaud:

richluvsound
08-28-2008, 10:09 PM
If only more companies treated us this way !

Good work ,Good luck

Rich

4313B
08-31-2008, 01:52 PM
Looks like Bryston is going to modify the 10b L-R after all, the email from them is below.Outstanding! :applaud:

John
08-31-2008, 08:18 PM
If only more companies treated us this way !
Rich


Uh Huh:D

Paky33
09-20-2008, 02:40 AM
Hello,
you can replace the internal resistance and to obtain the 250 Hz. But the L-R model is not done for HiFi.
You must buy the latest model of B10 Sub. The latest revision of the mainboard and power voard sounds much better than the old. There is more air and the scene is better. I experienced this with an old B10 and new B10 Sub.

neanderthal
10-04-2008, 03:22 PM
I received the Bryston 10B L-R back from Bryston Tuesday.Now all I need is to decide what amp to get for the highs. If anyone has had any first hand experience with the pass Labs X150 or the X150.5 I'd very much appreciate your input positive or negative. I have done alot of reading and have always heard positive comments on Pass Labs and McIntosh. I'd like to hear what a tube amp has to offer but I know because of my limited knowledge, ...OK no knowledge on repairing anything electrical so I need to stay away from them.

Ian Mackenzie
10-04-2008, 06:38 PM
I received the Bryston 10B L-R back from Bryston Tuesday.Now all I need is to decide what amp to get for the highs. If anyone has had any first hand experience with the pass Labs X150 or the X150.5 I'd very much appreciate your input positive or negative. I have done alot of reading and have always heard positive comments on Pass Labs and McIntosh. I'd like to hear what a tube amp has to offer but I know because of my limited knowledge, ...OK no knowledge on repairing anything electrical so I need to stay away from them..



Have a chat with porschedpm.

In my experience the X series works very well. The X.5 series has sweeter highs and better low level resolution with SE bias over the first few watts.

Depending on the producton run some of these amps are set for 30 db gain. The amp can be adjusted to the more nominal 26 db gain if you prefer.

Ian