[danlaix]

Hello guys, its been a while.

Just wanna know which of these 2 buffers do you prefer for
the Meta42? I know the buf634 wont fit into the meta42, but
who knows someone did mod the buf and put it nicely into the
board.
The reason why i ask is because the current output of the 2
buffers: EL->100mA BUF->250mA

Is it the higher the current the better?
Let me know what u think guys.
Thanks.

 

[tangent]

Quote:

Just wanna know which of these 2 buffers do you prefer for the Meta42?

Soon this question will be irrelevant, since only the BUF634 will remain.

Quote:

who knows someone did mod the buf and put it nicely into the board.

It's not too hard to make adapters. Also, the next version of the META42 board will use BUF634s, out of necessity.

Quote:

BUF->250mA

Only in the TO-220 package, and only when properly heat-sinked. The smaller packages seem to stop at about 150mA.

Quote:

Is it the higher the current the better?

All else being equal, yes. But, all else is not equal. You're talking about two entirely different circuit designs inside each buffer. Both datasheets have simplified schematics; check 'em out.

 

[morsel]

While we are on the subject, there is also the Intersil HA3-5002, which is not being used in the next META42 version due to high current draw, but which is a fine buffer nonetheless.

 

[mekanoplastik]

Quote:

Soon this question will be irrelevant, since only the BUF634 will remain

Tangent..how soon is that?

 

[danlaix]

anyone else out there who has any experience at all
using the BUFs in their Meta? Please contribute your
listening experience, thank you.

I know that the EL is no more in production, and tangent
has lots of them in stock. But still, i'm not trying to discourage
anyone from getting the ELs. The purpose of this thread is
just to get some feedbacks from the people here regarding
the sound output from these 2 buffers.

 

[tangent]

Quote:

how soon is that?

I don't have the statistics or the mass psychology savvy I would need to answer that question accurately. Put it this way: when I publically announce the next version of the META42, you can make some inferences from that. Until then, assume that I have enough buffers for the forseeable future.

Quote:

The purpose of this thread is just to get some feedbacks from the people here regarding the sound output from these 2 buffers.

Well, since you put it that way...you might instead ask the question "META42 vs. MINT?" since the MINT uses the BUF634 and has a similar enough circuit to the META42 that you can configure them similarly and then do a test. Probably there are enough people with one or more of both amps now to get a reasonable spread of answers to the question.

Personally, I find the BUF634 to have that characteristic Burr-Brown "dark" sound to it. In the same way that many people prefer this coloration in their op-amps, I'm hearing that some people like the sound of the MINT better than a META42. Changing the bandwidth of the buffer doesn't change the overall character, it just opens the sound up a bit, giving it some additional detail.

The EL2001 and '2 probably have the most balanced presentation of all the buffers I've listened to.

I prefer Analog Devices' better op-amps to any Burr-Brown op-amp, so it won't surprise anyone to hear that overall I prefer the EL2001/2 over the BUF634. The BUF634 is a nice chip, but I will miss the Elantecs when they are gone.

 

[jeffreyj]

Has anyone tried the LMH6718 yet? It's a dual "buffer" that sports some impressive distortion and noise characterisistics. It also costs a bit less than the BUF634 (whose datasheet omniously omits the distortion data!).

 

[Wodgy]

For what it's worth, I agree with Tangent's appraisal of the sound of the EL200x / BUF634 buffers. Personally prefer the sound of the BUF634, but only because I tend to prefer a darker sound.

 

[mekanoplastik]

*

 

[morsel]

Mek, Tangent is saying he does not know when because it is too difficult to predict. You assume the components sell at a constant rate and jump on Tangent for not giving you the answer you want to hear. Tangent is not your employee, nor does he answer to you. Be patient. We are working on the next version of the META42. We will let you know when we are ready to let you know.

 

[morsel]

Jeffrey, the LMH6718 is not an open loop buffer and it has a low maximum supply voltage of about 12V, which makes it unsuitable for our purposes.

I think the HA5002 is the best buffer atm, but the high quiescent current draw makes it suboptimal for small battery powered amps.

 

[aos]

I used LMH6718 - it's a current feedback buffer, right? Like all the other of their kind that I know of, it has untouchable bass (similar to EL2009) but it suffers the same problem as other current feedback buffers. It puts a really significant veil over the sound.

 

[mekanoplastik]

*

/end

 

[jeffreyj]

morsel said:
Quote:

Jeffrey, the LMH6718 is not an open loop buffer and it has a low maximum supply voltage of about 12V, which makes it unsuitable for our purposes.

How many volts do you need, morsel? The '6718 comes within 1V of each rail when driving 100R, and half a volt into 300R. With +/-4.5V rails you could put 8Vpp across a pair of HD-600s, or just shy of excruciatingly loud.

Other than that, your response did not seem germane to the thread topic as Danlaix was asking about whether putting a different buffer into the META42 was worth the trouble, not what buffer was going into the next version of the amp.

aos said:
Quote:

I used LMH6718 - it's a current feedback buffer, right? Like all the other of their kind that I know of, it has untouchable bass (similar to EL2009) but it suffers the same problem as other current feedback buffers. It puts a really significant veil over the sound.

Indeed it is... well, sort of. The gain is preset to +2 with internal 1k feedback resistors.

I've only *listened* to the LM6181, so I can't comment on how CFAs sound in general. If by "veiled" you mean "lacking in nuance or detail," then I would guess the cause to be poor distortion behavior, especially at crossover. Many CFA parts seem to have rather unimpressive distortion specs - typically given as -45 to -52dBc - but the LMH6718 caught my eye because it's spec is so much better than the average (-84dBc driving a 100R load).

I'm going to request some samples of it and a couple other chips next week for another project Ive got cooking so I'll give it a try. At 1/4th the price of the BUF634, it's definitely worth trying out.

 

[aos]

I only tested chips with very low distortion numbers, actually LMH6718 is a replacement for another chip (CLC5602 or CLC5632 I think) which I also tested. Even though they sport very respectable THD numbers, they just lack low level detail and are just not as lively sounding as good voltage feedback chips. They lack in detail and sound somewhat dead. That is not to say that they are useless.