Bryston Turntable

0 Members and 1 Guest are viewing this topic. Read 136695 times.

alexone

  • Full Member
  • Posts: 1976
  • Anthony Bower, Stan Rybbert, John Stoneborough
Re: Bryston Turntable
« Reply #140 on: 2 Jul 2016, 06:25 pm »

...nice idea to sell cartridges :thumb:. are you sure you will be offering only two of them?

al.

James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #141 on: 10 Jul 2016, 01:32 pm »
Hi Folks,

With the recent introduction of our new Phono stages and Turntables a number of customers have asked why we recommend Transformer based Step-Up devices for Moving-Coil cartridges over Head-Amps. I have put together some thoughts on it - please see below.


BRYSTON TF-2 MOVING COIL TRANSFORMERS

Moving-Coil Transformers

Step-up transformers for Moving-Coil cartridges are the most esoteric and misunderstood items in the world of hi-fi, and this partly explains why they are so seldom used. This is a great shame because the use of a good MC transformer gives the best possible performance from a moving coil cartridge. Moving–Coil cartridges have very little voltage output but significant current is available. So the MC transformer ‘transforms’ this small voltage at the output of the MC to the required voltage required by the Phono Stage in the preamplifier. It does this passively so no noise or distortion is added resulting in a much better signal to noise ratio.

Operating principle

Moving magnet cartridges, as their name implies, contain magnets which are moved by the stylus’ cantilever, and the movement induces the signal voltage in fixed coils in close proximity to the magnets. In moving coil cartridges the roles are reversed, so now the magnets are fixed and the coils move. The big advantage of moving coils is that the coils are much lighter (lower mass) than the magnets, so they are much more responsive to the motion of the stylus.

The big disadvantage is that the output voltage of moving coil cartridges is about 20dB lower than that of moving magnets, so an extra 20dB of gain is required. The extra gain can be provided by the phono-stage amplifier, by an external device called a head-amp, or by a transformer. The most commonly found solution is to increase the gain in the phono-stage itself, but in our opinion step-up transformers are still the best solution where ultimate performance is the objective.

Why use a transformer at all?

It used to be the case that a good signal-to-noise ratio was impossible to achieve from a moving coil cartridge without a step-up transformer. An extra 20 or 30 decibels of gain wasn’t a problem, but doing so with low noise using valves, transistors or op-amps was a problem. Modern transistors and op-amps can now offer much better signal-to-noise ratios but valves still usually need transformers to work successfully with low output moving coil cartridges. An alternative to the step-up transformer is the head-amp (or pre-preamp). This is a transistor or op-amp amplifier which raises the output of moving coil cartridges up to moving magnet level.

Apart from the issue of a lower noise floor, the sound quality of transformers is something their advocates swear by. The distortion produced by audio transformers is of a completely different nature to that produced by a transistor amplifier. The harmonic distortion in transformers is greatest at the lowest frequencies and falls rapidly as the frequency rises, whereas in transistor amplifiers distortion more usually rises as the frequency rises. More importantly, inter-modulation distortion tends to be lower in transformers than it is transistor amplifiers. The outcome is that although transformers aren't absolutely free of distortion (nothing is), the distortion is very benign compared to the distortion produced by many transistor amplifiers. This explains why the sound produced when a moving coil cartridge is used with a good transformer is so sublime and can create an open and spacious soundstage with amazing separation between instruments.

The case against transformers is simply one of cost. Transistors can be as cheap as a few pennies (or less when bought in sufficient quantities) whereas transformers always cost a lot more, by as much as a factor of several thousand, due to the expensive materials used in the core and the cost of the copper windings in terms of both material and labour.

Cartridge loading

Before considering how to match a moving coil cartridge with a transformer, it is worthwhile considering the effects of different loads on moving coil cartridges. When any signal source is connected to any load impedance a potential divider is formed by the source's output impedance and the load impedance. The usual rule for audio equipment in general is to feed the signal into a load at least ten times greater than the source impedance to avoid any significant signal loss, and this applies to moving coil cartridges as well. If the load impedance is 10 times greater than the source impedance the signal lost by the “pre-set volume control” is less than 1dB, ie nearly all the signal generated by the source is available to the following amplifier. Any loss of signal at the source/load interface is usually considered a bad thing as it compromises the signal-to-noise ratio. More signal is lost, ie the pre-set volume control is turned down more, if the load impedance isn't significantly higher than the source impedance.

When the source and load impedances are equal the signal loss is 6dB. When the source impedance is 9 times greater than the load impedance the signal loss is 20dB. Most modern moving coil cartridges have a source impedance of about 10 ohms and the “load impedance ten times the source impedance” rule suggests 100 ohms is a good choice for load impedance and causes less than 1dB of signal loss. This is well in line with the recommendations from many cartridge manufacturers (see the table of data below). Anything above 100 ohms should be equally suitable.

Does the cartridge's tonal balance change with load impedance? It certainly does if the cartridge is a moving magnet type, but low output moving coil cartridges are much less sensitive to changes in the load impedance. Users sometimes claim that higher load impedances produce a brighter sound than lower ones, but cartridge manufacturers tend be non-specific about recommended load impedances, often recommending a wide range or simply anything above a minimum impedance. The recommendation of Bryston is in line with most other cartridge manufacturers - that 100 ohms is a good value for most cartridges, and that the exact value is not critical as long as it is well above the cartridge's source impedance. One thing is certain, and that is that the load impedance should not be equal to the cartridge's source impedance.

A step-up Moving-Coil transformer is designed to accept the lower voltage output from the MC cartridge and increase the voltage to a point which is acceptable to the input stage of the standard MM phono section. The Bryston Moving-Coil step-up transformer is available in two versions...with a 20dB or a 30dB gain option. Your choice on which unit is most appropriate will be determined by the voltage output of your chosen cartridge.

•   From .1 to .2 mV we would recommend the 30dB version
•   At .3 mV we would say either version would work fine
•   From .4 to .5 mV or more we would recommend the 20dB version

An important point to consider when choosing which Step-up to use is you do not want to over-power or under-power the MM phono stage. Under-powering results in not having enough GAIN in the system and over-powering can result in voltage overload and the resultant distortion.

The big mistake most often made when selecting a transformer for a moving coil cartridge is to overlook the voltage required at the phonostage's input and instead try to make the impedances match so that, for example, a cartridge with a 5 ohm source impedance sees a 5 ohm load at the transformer's input. This approach takes the cartridge's impedance as the most important factor when in reality it should be the cartridge's output voltage.


James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #142 on: 12 Jul 2016, 07:24 pm »
Hi Folks,

Customers are asking for recommendations on cartridges for their Bryston Turntables.   So far have listened to a few and these seem to work very well.


BRYSTON RECOMMEDED CARTRIDGES



BENZ-MICRO                                RETAIL
            
ACE           L or M or H                   $1,190
            
GLIDER     L or M or H                   $1,585

« Last Edit: 11 Aug 2016, 07:42 pm by James Tanner »

abuhannibal

  • Jr. Member
  • Posts: 67
Re: Bryston Turntable
« Reply #143 on: 11 Aug 2016, 06:21 pm »
This looks like an amazing product, and FWIW - I may be in the minority but for me the traditional hinged dust cover is a major selling point. If you have cats or your SO lets cleaning people into the house, you gotta have one, and I am a bit miffed at having to spend pretty big $$ for a piece of lucite, which likely won't even stay in place when the furballs jump off it. :) So, do be aware that there are some of us out here who appreciate it - we can always take it off if we don't want it!

EDIT: Where can I audition one in the greater NY area, or Vermont?

CanadianMaestro

  • Restricted
  • Posts: 1760
  • Skepticism is the engine of progress
    • Hearing Everything That Nothing Can Measure
Re: Bryston Turntable
« Reply #144 on: 11 Aug 2016, 07:27 pm »
^ I had our machine workshop at the lab make a plexiglass rectangular top (not hinged) for my Ovation TT. Cost me about $100 all incl. It's heavy but has finger slots for easy lifting. Absolute must for dust shielding.

CanadianMaestro

  • Restricted
  • Posts: 1760
  • Skepticism is the engine of progress
    • Hearing Everything That Nothing Can Measure
Re: Bryston Turntable
« Reply #145 on: 11 Aug 2016, 07:32 pm »
I have a Clearaudio Virtuoso Wood MM, which retailed for around $900 ca. 2013. It's great for classical music and vocals.

Review:

http://www.stereophile.com/phonocartridges/737#8uyaBOS0UiL0PYgj.97

James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #146 on: 11 Aug 2016, 07:49 pm »
This looks like an amazing product, and FWIW - I may be in the minority but for me the traditional hinged dust cover is a major selling point. If you have cats or your SO lets cleaning people into the house, you gotta have one, and I am a bit miffed at having to spend pretty big $$ for a piece of lucite, which likely won't even stay in place when the furballs jump off it. :) So, do be aware that there are some of us out here who appreciate it - we can always take it off if we don't want it!

EDIT: Where can I audition one in the greater NY area, or Vermont?

HI

We start shipping the turntables at the end of this month.

The dust cover also adds some extra mass to the plinth of the turntable if massive enough.  Cheap turntables with extra light plastic covers can actually introduce some resonance.  Our Bryston dust covers are double thickness and solid and do not have that problem. 

james



James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #147 on: 15 Aug 2016, 02:43 pm »
Hi Folks,

Link to the new Bryston Phono products on our website:

http://bryston.com/products/phono/BP-2.html

james

sweetspot

  • Jr. Member
  • Posts: 133
Re: Bryston Turntable
« Reply #148 on: 15 Aug 2016, 03:21 pm »
James, can this be used with the MPS-1?

James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #149 on: 15 Aug 2016, 03:55 pm »
James, can this be used with the MPS-1?

No sorry just the PS-3.  We are working on it working with the MPS-2 as well.

james


Johnny2Bad

Re: Bryston Turntable
« Reply #150 on: 15 Aug 2016, 05:07 pm »
I just received a set of Morrow phono cables. I opted for the PH-5 and even though they require long breakin I can tell you that the detail is incredible. They blow the doors of my Audioquest Diamond backs and audio art cable with furitech connectors. There is a huge sale right now. I got 25% off but for this weekend you get 25% off plus an additional 20%. They have a 60 day return policy. I don't usually recommend cables as everyone has their favorites, but you owe it to yourself to try these.

http://morrowaudio.com/

Don't get me wrong, I like the Morrow cables. But they are on sale every day (would be illegal in Canada, by the way; you have to offer the product for a majority of the time at the regular price in order to offer a sale price; otherwise it's a classified as a Deceptive Trade Practice).

But the point is, there is no need to rush.

gene9p

  • Full Member
  • Posts: 597
Re: Bryston Turntable
« Reply #151 on: 15 Aug 2016, 08:41 pm »
Don't get me wrong, I like the Morrow cables. But they are on sale every day (would be illegal in Canada, by the way; you have to offer the product for a majority of the time at the regular price in order to offer a sale price; otherwise it's a classified as a Deceptive Trade Practice).

But the point is, there is no need to rush.

O Canada.....

techguy0192

  • Jr. Member
  • Posts: 143
Re: Bryston Turntable
« Reply #152 on: 16 Aug 2016, 02:21 am »
I see the bryston.com page has been update with info on the new turntable.  It looks great! :thumb:  I was a little surprised to see the three year warranty.  Otherwise, great work as always.

James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #153 on: 19 Aug 2016, 08:33 pm »

Hi James


Ted Green is one of the best read, most respected trade editors in our industry.

For the entire quarter, do you know what has the most hits on his site? Out of all the stories about the big guns like Crestron…this story rules as #1:

http://www.strata-gee.com/feeding-growing-vinyl-beast-bryston-launches-blp-1-turntable/
 
Amazing!!
 
Micah Sheveloff

Samurai7595

Re: Bryston Turntable
« Reply #154 on: 20 Aug 2016, 01:10 pm »

Hi James


Ted Green is one of the best read, most respected trade editors in our industry.

For the entire quarter, do you know what has the most hits on his site? Out of all the stories about the big guns like Crestron…this story rules as #1:

http://www.strata-gee.com/feeding-growing-vinyl-beast-bryston-launches-blp-1-turntable/
 
Amazing!!
 
Micah Sheveloff


Very cool!  :thumb:

G E

  • Full Member
  • Posts: 624
Re: Bryston Turntable
« Reply #155 on: 20 Aug 2016, 02:40 pm »
Don't get me wrong, I like the Morrow cables. But they are on sale every day (would be illegal in Canada, by the way; you have to offer the product for a majority of the time at the regular price in order to offer a sale price; otherwise it's a classified as a Deceptive Trade Practice).

But the point is, there is no need to rush.

Another big Morrow cables fan here.

I agree with this- Mike runs "sales" all the time. Once in a while they are real sales, a straight up 50% off or thereabouts. Waiting for the better sales on the used cables is a good strategy. I also see them on A'Gon fairly often.


CanadianMaestro

  • Restricted
  • Posts: 1760
  • Skepticism is the engine of progress
    • Hearing Everything That Nothing Can Measure
Re: Bryston Turntable
« Reply #156 on: 26 Aug 2016, 02:15 pm »
Novelty is always a powerful stimulant for exploration......and often subsequently, purchasing.

James Tanner

  • Facilitator
  • Posts: 20448
  • The Demo is Everything!
    • http://www.bryston.com
Re: Bryston Turntable
« Reply #157 on: 9 Sep 2016, 11:19 am »
Hi Folks,

Now that the Bryston turntable is getting released I have had a number of questions on the best way to figure out the Resonant Frequency of a particular cartridge on the Bryston Tonearm.  Don't let this scare you but the math looks like this:


FORMULA FOR COMPLIANCE OF CARTRIDGE AND MASS OF TONEARM FOR BEST RESONANCE MATCHING

September 2016


Hi Folks

With any tonearm/cartridge combination you are attempting to place frequency resonance ideally between 8-12Hz to attain the best performance.

The formula for calculating the tonearm/cartridge frequency resonance is:

FR = A ÷ √ M × C
 
Where:

A = 1.000 ÷ 2 π = 159, 23 (you can also use the fixed value of 159)
M = sum of all masses (tonearm, screws and cartridge)
C = compliance (at 10 Hz)
 
The Titanium arm supplied with the Bryston BLP1 Turntable is 10g mass.

For example:
Lets say your cartridge weighs 7.5g and has a compliance of 12cu/dyne/10 Hz (Please remember that often the Japanese cartridges indicates the compliance at 100Hz (not 1,000) which means you must double it in that case for the correct calculation).

IF you want to figure out the FR of your tonearm/cartridge you have to add the different masses:

7.5g (cartridge)
+ 10g (arm)
+1g (screws) = total 18.5g.

Then you multiply 12 x 18.5 = 222
The square root is around 14.9

So with the Tonearm on our Bryston BLP-1 Turntable the frequency resonance would be: … 159 ÷ 14.9 = 10.67 Hz; a value that places exactly in the desired interval of 8 -12 Hz considered the best range for frequency resonance of the tonearm/cartridge combination.


James Tanner
Bryston


vegasdave

  • Full Member
  • Posts: 4039
    • My online rock magazine-Crypt Magazine
Re: Bryston Turntable
« Reply #158 on: 9 Sep 2016, 01:24 pm »
sorry james, that made my head hurt, lol. i'm very poor at math, lol.

Johnny2Bad

Re: Bryston Turntable
« Reply #159 on: 15 Sep 2016, 05:17 pm »
sorry james, that made my head hurt, lol. i'm very poor at math, lol.

There is hardly any math involved. Two button presses on a calculator (well, plus a little simple addition, but if that scares you, you should go back to your public school and shoot your 4th grade teacher).

Your eyes must glaze over at the mere sight of an equation. Not that you're alone, but I do find it an amusing aspect of human nature.