Thanks for your help peranders,
Will let you know when they arrive. Also if you require funds for shipping dont hesitate to inform me.
Thanks again!
Will let you know when they arrive. Also if you require funds for shipping dont hesitate to inform me.
Thanks again!
I have added a table in the wiki page for missing parts. These notes are only for me and Rhys so please don't edit anything there please.
As you can see we can all see how many parts that are missing and it's not hopeless to get it fixed. I talked to Rhys in the phone today and I'll hope he does as much he can while I'm away. I'll be back next weekend.
As you can see we can all see how many parts that are missing and it's not hopeless to get it fixed. I talked to Rhys in the phone today and I'll hope he does as much he can while I'm away. I'll be back next weekend.
Update: The rest of the parts will be going to Per-Anders early next week, using DHL again. This should hopefully not cause a delay as PA has stated he will be away.
And again, a huge thanks to Per-Anders for helping me out
And again, a huge thanks to Per-Anders for helping me out
juluska said:
Looks good, I am going to try the unbalanced version (BPA150) first also.
By the way, where did you get the connectors for the boards? Do you have the digikey or mouser part number? Thanks.
few questions
what speakers do you use (efficiency, impedance, etc.)?
did you play loud? the balanced (I assume you mean the bridged configuration) is aimed on providing more power (if at all needed).
how hot are the LMs getting? you did not tighten them to the heat sink so I guess you did experienced extreme temperatures.
if I correctly recall, I saw a post of yours describing noise when connecting in bridge configuration. is it solved or is it the reason you don't use that configuration at the moment?
With some luck and some more of that good back wind in Sheffield more picture of that kind are expected!
what speakers do you use (efficiency, impedance, etc.)?
did you play loud? the balanced (I assume you mean the bridged configuration) is aimed on providing more power (if at all needed).
how hot are the LMs getting? you did not tighten them to the heat sink so I guess you did experienced extreme temperatures.
if I correctly recall, I saw a post of yours describing noise when connecting in bridge configuration. is it solved or is it the reason you don't use that configuration at the moment?
With some luck and some more of that good back wind in Sheffield more picture of that kind are expected!
Re: few questions
loudspeakers: old B&W DM310, 8ohm, 90db
i don't play it very loud but i'm building this amplifier for my sister, who has B&W Matrix 804 loudspeakers, so i think more power would be better.
LM3886 run hotter than expected, i don't tight them, it's a provisional heatsink.
Yes, i tested the drv134 boards but not bridged. I connected two of the three outputs to my chipamp.com LM3886 monoblocks and i found lot of noise, similar to the noise produced by a cassette deck without noise reduction, but this isn't the way to connect it.
A question. What about the resistor in the drv134 boards? I didn't use it. Is this correct?
shmulik said:
loudspeakers: old B&W DM310, 8ohm, 90db
i don't play it very loud but i'm building this amplifier for my sister, who has B&W Matrix 804 loudspeakers, so i think more power would be better.
LM3886 run hotter than expected, i don't tight them, it's a provisional heatsink.
Yes, i tested the drv134 boards but not bridged. I connected two of the three outputs to my chipamp.com LM3886 monoblocks and i found lot of noise, similar to the noise produced by a cassette deck without noise reduction, but this isn't the way to connect it.
A question. What about the resistor in the drv134 boards? I didn't use it. Is this correct?
regarding the resistors, in the drv134 TI papers they appear only in testing circuits and not in the typical usage one.
regarding noise, how did you connect the various grounds (input signal ground, drv supply, bpa supply)? were they all connected to a ground star? according to your description it is more like hiss than hum but it is hard to say. maybe someone who knows what he is talking about should comment.
regarding noise, how did you connect the various grounds (input signal ground, drv supply, bpa supply)? were they all connected to a ground star? according to your description it is more like hiss than hum but it is hard to say. maybe someone who knows what he is talking about should comment.
Jululska,
I remember when I first used the drv 134 pcb for my bpa300 there was a lot of noise. I tryed different ground setups, very tightly twisted leads and never got the noise to go away.
I eventually made an amp with the bpa150 setup. I truly think the transformer setup for bridge in this amp is the way to go. That is the approach Jeff Rowland used in the original unit.
I see from your post that you have encountered the HOT nature of these chips. Were you prepaired for that much heat? I have always been skeptical of Alexw88 amps with the limited ventilation in his cases. He must have some very tame speakers.
In any case this little amp does sound truly awesome. Good luck on the enclosure. Post some finals when you get time.
Rhys,
Feeling a little bit more at ease now I hope.
Tad
I remember when I first used the drv 134 pcb for my bpa300 there was a lot of noise. I tryed different ground setups, very tightly twisted leads and never got the noise to go away.
I eventually made an amp with the bpa150 setup. I truly think the transformer setup for bridge in this amp is the way to go. That is the approach Jeff Rowland used in the original unit.
I see from your post that you have encountered the HOT nature of these chips. Were you prepaired for that much heat? I have always been skeptical of Alexw88 amps with the limited ventilation in his cases. He must have some very tame speakers.
In any case this little amp does sound truly awesome. Good luck on the enclosure. Post some finals when you get time.
Rhys,
Feeling a little bit more at ease now I hope.
Tad
Could everyone with claims send à message to me please? The persons I am going to send stuff are on the wiki list. I will conducting Rhys' business forever.
help
I've just finish to test two pa150 boards in bridge mode with drv134/ that1646 and Rhys pcbs. In both cases there is an unsupportable hiss that i can't eliminate. I think it's possible the pcb design is poor. Has anyone test these pcbs? Is there any easy design i can build in a protoboard? Now that i have these balanced drivers i want to probe other design before go for expensive transformers.
Thanks
tryonziess said:
I've just finish to test two pa150 boards in bridge mode with drv134/ that1646 and Rhys pcbs. In both cases there is an unsupportable hiss that i can't eliminate. I think it's possible the pcb design is poor. Has anyone test these pcbs? Is there any easy design i can build in a protoboard? Now that i have these balanced drivers i want to probe other design before go for expensive transformers.
Thanks
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