PKay Posted February 6, 2023 Share Posted February 6, 2023 A friend of mine has lent me this amp and I am a little puzzled by the instructions (which are scant at best). Perhaps it lost a bit in the translation but I can't be too sure. My speakers are Graham LS 5/9 which are 8 ohms and do suit the amp. The amp has no markings on the back for speaker connections but has 4 inputs for left channel and 4 for the right channel. The connection diagram is confusing. Link to comment Share on other sites More sharing options...
muon* Posted February 6, 2023 Share Posted February 6, 2023 I can see how it is confusing. I'm confused by it Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 I think that it is an internal adjustment diagram ie to adjust it with the top off. The manual online says internal adjustment. Just my 2c… Link to comment Share on other sites More sharing options...
muon* Posted February 6, 2023 Share Posted February 6, 2023 Specs say two sets of speaker outputs for bi-wiring. Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 1 minute ago, MTL said: I think that it is an internal adjustment diagram ie to adjust it with the top off. The manual online says internal adjustment. Just my 2c… That makes sense. Would you suggest using the connections on the diagonal or just straight in a row? Link to comment Share on other sites More sharing options...
muon* Posted February 6, 2023 Share Posted February 6, 2023 2 minutes ago, MTL said: I think that it is an internal adjustment diagram ie to adjust it with the top off. The manual online says internal adjustment. Just my 2c… Not doubting you. But I'm trying to work it out inside and be buggered if I know. Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 Looks like it’s factory set for a certain impedance so no need to change anything 1 Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 (edited) Look just above the terminals. Seems confusing for sure but I think that’s what they mean inverts phase also Edited February 6, 2023 by MTL Extra info 2 Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 53 minutes ago, MTL said: inverts phase also What does that mean in terms of cable connection? Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 (edited) Attach red of the speaker cable to the black terminal on the amp and vice versa. This is for both left and right speakers .That will correct the phase Edited February 6, 2023 by MTL Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 29 minutes ago, MTL said: Attach red of the speaker cable to the black terminal on the amp and vice versa. This is for both left and right speakers .That will correct the phase Here’s a photo of how I set it up. Will it damage my speakers if I swap the polarity? 1 Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 Nope. No damage at all. 1 Link to comment Share on other sites More sharing options...
Guest deanB Posted February 6, 2023 Share Posted February 6, 2023 From the Jadis website - WHY THE JADIS AMPLIFIERS ARE EQUIPPED WITH TWO PAIRS OF TERMINALS FOR THE SPEAKERS? The two pairs of terminals for the speakers are connected in parallel inside the unit in order to allow the user to do a bi-wiring system on his speakers. So not the usual 8ohm and 4ohm outputs found on many valve amps. Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 @PKayso how does it sound? Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 9 minutes ago, MTL said: @PKayso how does it sound? Incredible. This is the best I’ve ever heard my system sound. The dynamic range is enormous, quiet passages are so clear and the grip on the speakers gets every bit of bass out of my Graham LS5/9s. Orchestral pieces are huge, this is a really wonderful amp. I’ll be sorry to return it. The amp puts out a lot (and I mean a lot) of heat. Thankfully there is a nice cool breeze tonight. 1 1 Link to comment Share on other sites More sharing options...
MTL Posted February 6, 2023 Share Posted February 6, 2023 5 minutes ago, PKay said: I’ll be sorry to return it Then don’t. You know what they say-it’s not a matter of whether you can live with it, but whether you can live without it 1 Link to comment Share on other sites More sharing options...
metal beat Posted February 6, 2023 Share Posted February 6, 2023 59 minutes ago, PKay said: Here’s a photo of how I set it up. Will it damage my speakers if I swap the polarity? Peter, from this picture you have not inverted the phase. Have you done it at the speakers? Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 1 minute ago, metal beat said: Peter, from this picture you have not inverted the phase. Have you done it at the speakers? I did it at the speakers. It seems like a ridiculous idea to have to invert connections. I’m not sure why they do it that way. 1 Link to comment Share on other sites More sharing options...
metal beat Posted February 6, 2023 Share Posted February 6, 2023 (edited) 9 minutes ago, PKay said: I did it at the speakers. It seems like a ridiculous idea to have to invert connections. I’m not sure why they do it that way. I have had 20+ years with cj preamps and they all reverse phase. They only have one amplification stage - very pure and direct sound. That is probably what is happening with the Jadis, giving you an odd phase number at the output stage. When you have time. Reverse the speaker cables at the amp outputs and have the speaker end normal connection. It will be interesting if you hear any difference Edited February 6, 2023 by metal beat 2 Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 3 minutes ago, metal beat said: I have had 20+ years with cj preamps and they all reverse phase. They only have one amplification stage - very pure and direct sound. That is probably what is happening with the Jadis, giving you an odd phase number at the output stage. When you have time. Reverse the speaker cables at the amp outputs and have the speaker end normal connection. It will be interesting if you hear any difference Thanks Shane. I’d be surprised if I could hear a difference. Link to comment Share on other sites More sharing options...
AuDrew Posted February 6, 2023 Share Posted February 6, 2023 1 hour ago, deanB said: From the Jadis website - WHY THE JADIS AMPLIFIERS ARE EQUIPPED WITH TWO PAIRS OF TERMINALS FOR THE SPEAKERS? The two pairs of terminals for the speakers are connected in parallel inside the unit in order to allow the user to do a bi-wiring system on his speakers. So not the usual 8ohm and 4ohm outputs found on many valve amps. It will be worth the while to see if bi-wiring makes a perceptible impact on the sound, even if your Grahams are not bi-wirable @PKay Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 The Jadis is huge. At 40kg not easy getting it up a tight path. 1 Link to comment Share on other sites More sharing options...
AuDrew Posted February 6, 2023 Share Posted February 6, 2023 It certainly looks a beast… but a beautiful beast! 2 Link to comment Share on other sites More sharing options...
PKay Posted February 6, 2023 Author Share Posted February 6, 2023 11 hours ago, metal beat said: I have had 20+ years with cj preamps and they all reverse phase. They only have one amplification stage - very pure and direct sound. That is probably what is happening with the Jadis, giving you an odd phase number at the output stage. When you have time. Reverse the speaker cables at the amp outputs and have the speaker end normal connection. It will be interesting if you hear any difference I reversed the polarity at the amp end this morning. It still sounds great and I’m not sure I could reliably pick the difference. I’ll leave it reversed at the amp end. 1 Link to comment Share on other sites More sharing options...
ex turpi hifi Posted Tuesday at 04:09 PM Share Posted Tuesday at 04:09 PM (edited) On 06/02/2023 at 8:29 AM, PKay said: Here’s a photo of how I set it up. Will it damage my speakers if I swap the polarity? Why did you connect both cables to the right-most (or left most if looking from back) set of posts in each grouping? I'm guessing it doesn't matter but I'm wondering also about how to connect a sub to an amp like this. Edited Tuesday at 04:11 PM by ex turpi hifi Missed out some text Link to comment Share on other sites More sharing options...
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