Superbuffer instead of OPAMP

[Sigurd Ruschkow]

Hi All,

my preamp is still in the designphase and I am now considering using a discrete lineamp or a buffer instead of an OPamp.

As I only need 0 or maybe 6 dB of gain for my CD player and tuner,
a buffer with just some gain might be even better sounding than the best of the best of OPamps.

Borbely Audio has both a lineamp and a buffer he calls "superbuffer".

The design below looks rather straightforward and good to me.

Has anyone some knowledge of Borbely's "Superbuffer"?

An externally hosted image should be here but it was not working when we last tested it.

Sigurd

 

[PMA]

The success of Borbely's circuits depends on use of particular JFETs, many of them are discontinnued now. Are you able to get them?

 

[Sigurd Ruschkow]

I plan to buy the kit. That is the easiest way to get the components
Also, I do not have the facility to make a PCB, so it will be the kit.


Sigurd

 

[Upupa Epops]

Go on, this is best solution, Borbelly's things are excellent, 'cos he has it in own head quite clear .

 

[Sigurd Ruschkow]

Upupa - what kind of experience do you have of Borbely's designs? How did it sound? Any problems?



Sigurd

 

[PMA]

Borbely's amps are one of the sources of design of the Upupa Epops's amps (see driving stage of dc102 for example). And the UE amps are one of the best I have ever heard.

 

[peranders]

Sigurd, notice that Erno's buffer actually is a current feedback amp but his thig is to use jfet's and mosfets.

I'll imagine that his amp is pretty good if you can get good transistors. I have also want ed to make soem good jfet amp but good jfets are a bit hard to get in Sweden and I'm too lazy to import.....

Erno's design is pretty straight forward and there are no weird things.

 

[patriz]

I have built the Borberly all fets crossover that employ the superbuffer.
It was a real pain to find all the fets, some were bought directly from Erno, but I was rewarded with a wonderfully sounding xo .
It is by a wide margin better than my previous opa604 based xo.
Strongly reccomended..
Giorgio

 

[hjelm]

As for JFET's in Sweden. Bhiab Bhiab site Had some that i couldn't find aywhere else, in sweden. But since you are buying the kit then it doesn't matter.

 

[Sigurd Ruschkow]

One can buy the JFETs for the super buffer from Toshiba in Japan. None of them are discontinued.



Sigurd

The success of Borbely's circuits depends on use of particular JFETs, many of them are discontinnued now. Are you able to get them?

 

[Upupa Epops]

To Sigurd : Directly from Toshiba ? One hundred thousands ? Or milion ?

 

[Sigurd Ruschkow]

As long as one can get them, they are not discontinued, right?

One can always ask Borbely if you can buy some.







Sigurd

 

[bear]

Afaik Erno will sell you some fets in most cases.

here in the USA I can supply many japanese types, and have quite a few here for my own use/products...

_-_-bear

 

[Sigurd Ruschkow]

Borbely AUdio can sell you the JFETs he uses in his kits. Check out the new price list at

Borbely Audio high end component Price List



SIgge

 

[Sigurd Ruschkow]

I got me the Superbuffer from Borbely Audio. I decided on the Teflon PCB and the part Caddock upgrade tgether with the high current optput option.

I also got some special rubber "feet" instead of the normal metal PCB fasteners.

Assembly was a piece of cake due to the special packing of the different components.

Here are some photos I took:

Sigge

Hi All,

my preamp is still in the designphase and I am now considering using a discrete lineamp or a buffer instead of an OPamp.

As I only need 0 or maybe 6 dB of gain for my CD player and tuner,
a buffer with just some gain might be even better sounding than the best of the best of OPamps.

Borbely Audio has both a lineamp and a buffer he calls "superbuffer".

The design below looks rather straightforward and good to me.

Has anyone some knowledge of Borbely's "Superbuffer"?

An externally hosted image should be here but it was not working when we last tested it.

Sigurd

 

[hjelm]

Really nice.
How much did it cost in the end, approximately?
Why did you go for the caddock's have you heard them or did someone else say they were better?

Which CD player are you going to put it in?

What about sonics? Have you listened to it yet?

 

[Sigurd Ruschkow]

Hjelm,
the prices are as follows (from the Borbely Audio price list at http://www.borbelyaudio.com/pics/012005 kits.pdf :

Superbuffer Stereo with Teflon PCB: 150 Euros
Caddock Upgrade: 40 E
High Current Output: 16.5 E
6 db Gain Upgrade 10 E
Rubber Feet: 32 E

Dual Power Supply (Rectifier kit /309):135 E

Double dual Regulator (EB202/254): 185 E

In total: 568 Euros


I am still awaiting some special double-shielded transformers (toroid) so I have not listened to the kits yet.

I will use a stepped ladder attenuator with Dale resistors for most levels but for my preferred listening levels there will be Caddock MK132s installed.
ELMA switch.

I am not that fond of having "normal" metal film resitors in the signal path and that was the reason that I ordered the Caddock upgrade.

This preamp will have WBT Next Generation Silver chassie RCA connectors and internal wiring will be cotton insulated bare silver wire for the signal path and also for the power supply wires.

The CDplayer is a Harman/KArdon HD7525 with a discrete analog section. I have made some modifications to this CDplayer, and will do some more modfications when the preamp is finished. Interconnect cables are soldered directly before the muting switch inside the CDplayer. I am using Audio Consult't enamel insulated silver wire and cotton insulation together with WBTs Next Generation Silver RCA connectors for this interconnect cable.



Sigge

 

[Upupa Epops]

And whatabout are you dreaming ? Monocrystalic gold wires insulated by spider fibre ?

 

[AndrewT]

Hi sigurd
are your example prices for 1 stereo pair or ten stereo pairs?
regards Andrew T.

 

[Sigurd Ruschkow]

No need to be sarcastic.

The prices are for one stereo pair.

Dreaming? Who's dreaming? I am not.
Audio Consult's silver wire is here, and so is 4 pairs of WBT's NExtGen Silver xhassie RCA,
and so is 4 pairs of WBT's NextGen Silver RCA plug.

If you have a dream - make it come true!
I try to.



Best
Sigurd Ruschkowski