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Old 23rd December 2012, 02:32 PM   #11
redjr is offline redjr  United States
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Originally Posted by TheDealer View Post
...I cannot understand how sellers could send boards without testing and now these gentlemen (one of them an all time busy chinese) care less in support. I am going meanwhile angry. This is my 2. "defect" board of them[/B]
Sorry to hear you've had some trouble with support and in-action from your Chinese supplier. According to LJM_LJM, there are only two (2) authorized dealers for his L series class d amps; along1986090 and zoe_tsang. Others may claim they are LJM design/construction, but I've seen other implementations of the L series that may contain inferior parts. I wish I could offer more concrete help with your issue, but I can personally vouch for 'along' and despite the language barrier, he tries to reply to direct support questions. I know from personal experience. Since then, his shop has gotten most of my audio DIY business over the past year. Good luck.

Rick
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Old 23rd December 2012, 07:06 PM   #12
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Hi I have had 6 of these boards from along and many emails to him and he has always been very helpful and prompt in replying. The voltage on my boards is 65.5v and the offset is not more than 3m/v at the output terminals. My tri wired tri amped system has been working now for about 4 weeks with no problems apart from the odd squeal when I switch off.... any suggestions why ?
Alec
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Old 23rd December 2012, 09:26 PM   #13
redjr is offline redjr  United States
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Hi I have had 6 of these boards from along and many emails to him and he has always been very helpful and prompt in replying. The voltage on my boards is 65.5v and the offset is not more than 3m/v at the output terminals. My tri wired tri amped system has been working now for about 4 weeks with no problems apart from the odd squeal when I switch off.... any suggestions why ?
Alec
Are you using a speaker delay relay circuit with your amps? These will normally disconnect immediately upon power-off thus eliminating the squeal heard from the speakers.
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Old 23rd December 2012, 10:05 PM   #14
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No I haven't got any speaker delay circuits wasn't sure whether having relays in the output signal path would degrade the signal...
Alec
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Old 24th December 2012, 12:22 AM   #15
redjr is offline redjr  United States
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No I haven't got any speaker delay circuits wasn't sure whether having relays in the output signal path would degrade the signal...
Alec
I've never had an issue with them, but I guess I'm not that sensitive to any signal degradation. Perhaps some of the purists here may beg to differ. I install them in all the amps I build. They certainly eliminate any power-on/off thump though.
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Old 24th December 2012, 12:26 AM   #16
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Originally Posted by redjr View Post
I wish I could offer more concrete help with your issue, but I can personally vouch for 'along' and despite the language barrier, he tries to reply to direct support questions.
Thanks mate. I know along from past deals with him. I was every time pleased with quality and communication. What the hell I bought not these boards also there ...
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Old 24th December 2012, 07:30 AM   #17
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Originally Posted by redjr View Post
I've never had an issue with them, but I guess I'm not that sensitive to any signal degradation. Perhaps some of the purists here may beg to differ. I install them in all the amps I build. They certainly eliminate any power-on/off thump though.
Can you give me a link to the ones you use ?
Alec
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Old 24th December 2012, 02:40 PM   #18
redjr is offline redjr  United States
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Can you give me a link to the ones you use ?
Alec
Hi Alec,

Sure thing.. They are from Cristi over at Connexelectronic. Here's the link. The cool thing about these is they can be powered both from AC or DC voltages. So if you're using an SMPS with a low-voltage AUX DC out you're good to go. Small and convenient! Cristi also makes some very good SMPS modules. I'm presently using 2 of his models in a couple of amps I've built and am very happy with them. Quality is first rate.

Happy Holidays from across the pond.

Rick
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Old 24th December 2012, 02:59 PM   #19
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Many thanks I thought "along" might do them but he's shut for the holiday so will have a look after the holidays..
All the best for the Holiday Season thankfully no floods here...
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Alec
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Old 24th December 2012, 03:49 PM   #20
redjr is offline redjr  United States
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Many thanks I thought "along" might do them but he's shut for the holiday so will have a look after the holidays..
All the best for the Holiday Season thankfully no floods here...
Regards
Alec
Alec,

along does sell them too - that I've used before. It was the dual AC/DC voltages that Cristi's model offers that made them more appealing once I started using SMPS in my builds. Both will work - it just depends what secondary low-voltages you have available to power them, AC or DC.

Rick
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