Considering Tom's skills and the results already published, the datasheets of the lm4562/lme49724 give quite a good idea of what's going to happen. I expect no big surprise.
On the topic of the useful measurements, a thd vs frequency sweep at various input impedances might be good to have for those who consider using the buffer after a pot (in SE mode). From Self's measurements on the lm4562, there's probably little to show after a 10K pot though.
On the topic of the useful measurements, a thd vs frequency sweep at various input impedances might be good to have for those who consider using the buffer after a pot (in SE mode). From Self's measurements on the lm4562, there's probably little to show after a 10K pot though.
It seems possible but since I don’t have a UB in front of me I can’t confirm the spacing. I will have one on order to play with in the future though. Tom might be able to confirm.
Best,
Anand.
Yes, the Recom look very nice. And check out this universal adapter board they have to mount most of their modules. $14 on Mouser.
Link
I would be interested in the multi tone IMD results at 10 volt output and 600R input impedance. Along with 2K input impedance. I would like to see how this board compared to the LM4562 datasheet under these conditions. Because IMD is a much better indicator of sound quality than THD+N.
Attachments
Looks like it is a little too wide. I measured the board drawing and the hole spacing is approximately 3.3mm. You could cut it apart into single sockets.
Nicely done, Eagle Eye! I just checked the layout. The hole spacing is 130 mil = 3.30 mm. It's a standard 1206 footprint with holes in the centre of the pads. I used that footprint to allow for the use of 1206 SMD resistors and leaded (PTH) resistors. The holes are 30 mil (0.76 mm) in diameter.
Tom
I am one of the many interested in this board for a Purifi amp buffer. And I'm trying to figure out if this buffer will offer higher performance than the one included on the Purifi input board already. Many others have decided to upgrade to this board. I was assuming it was because it offered better performance. But in this application the buffer will need to drive up to 10 volts into 2.2K. Being a novice, I was just following the herd and assuming the professionals on this forum know best, and they made this decision based on being far more knowledgable than me. And Tom never expressed any concerns either regarding this board being used in this application.
So please once again, would it be possible to ask this simple question without ridicule?
Is there something funny about being a newcomer to the forum? Are you only allowed to ask questions after a certain period of time? I signed up here because there is a discussion going on regarding the Purifi amplifiers which I plan on buying. Outside of these amplifiers and these buffers I have no other interest in what's going on with this forum. Or the paranoid conspiracy theories that seem to be floating around among long term members.
Not at all. Generally newcomers are welcomed ... assuming they're newcomers, and not just banned users of years past who have signed up under a different username. I'm sure it's purely coincidental that you and "Class D" have the exact same approach in your questions and ask identical questions within moments after signing up on the forum. I'm sure it's also purely coincidental that you signed up just after "Class D" was put in the "sin bin".
Others are onto you as well: Brainstorming Purifi 1et400a amps
Tom
I have been following the Purifi thread, and was on the fence about ordering your buffers. But when class d brought into question the suitability of this board for a Purifi buffer, I also became concerned. Anyways your refusal to answer this question makes it very clear that this board is not suitable for this application. So I will look elsewhere.
I haven't refused to answer. In fact, I committed to answering your questions in Post #116 and again in Post #118. I didn't think your question in Post #172 required an immediate response, so I just added it to the list of measurements in your request. But if you're now taking your toy and going home, I guess I can mark those action items as "no longer needed" and move on with my life.
Tom
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