Thanks for the heads up fortunately I have a purpose built adapter box for use off the speaker terminals for that purpose.
Thank you very much! I figured it out. Now the next step is to wire balanced in transformers to SE…to make it work with this amp. Has anyone tried that ?
Alright! I figured it out with balanced input transformers coupled to unbalanced. The next step is to get it in properly
So as promised. I have uploaded a PDF detailed build here including all the modifications and so on. You can download it and check it out. It may help others who are interested in building this kit as well
Click the link above to download , and it is 1GB!!
Click the link above to download , and it is 1GB!!
The link seems to be broken. Have you considered building an external transformer based XLR to RCA box?
Thanks for the respond. I was too tired and didn’t check. Here it is again
I thought about the external solution, but I wanted to keep the purity and integrity of the signals. So, here it is internally
I thought about the external solution, but I wanted to keep the purity and integrity of the signals. So, here it is internally
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I wanted to say that's a really impressive write up and commend you for the efforts gone to in providing the pdf of your build it will I am sure become a invaluable reference for anyone wishing to build the amp either stock or as balanced.
I am glad to share. However, I have a problem with Jensen transformers. These kinds are too sensitive and can cause hum if nothing is playing and volume pots are cranked to more than 80%😢. Will have the Lundahl coming and see if it is going to be any better. Crossing fingers
Ugh, I shouldn’t just blame on the Jensen right away lol!!! Anyways, experimenting and trying modify the amp are both not an easy tasks. They perhaps work as they should when building a separate box for them. There is something funky going on here and it isn’t the Jensen faults. I will wait on for that Lundahl and see if I can do anything further
Have anyone tried
Audio Note Capacitor 0.1uF 600Vdc Silver Foil
The dimensions seems to fit the Decoupling caps places
Audio Note Capacitor 0.1uF 600Vdc Silver Foil
The dimensions seems to fit the Decoupling caps places
Whitigir, did you end up trying Audionite caps?
Picked up a pair of RCA 2A3 NOS and spending this evening listening to it. Also have 2785B from Victor, now deciding if I should put it into 8900 or 8600….any suggestions?
Picked up a pair of RCA 2A3 NOS and spending this evening listening to it. Also have 2785B from Victor, now deciding if I should put it into 8900 or 8600….any suggestions?
Nice !!!! Been thinking about also getting WE 300B, but right now
I am fixated by 2A3 sound. RCA 2A3 is to die for. I have 1971 date code and it opens up 8900 to another higher level of 3D soundstage. Don’t get me wrong Cossor/Linlai 2A3 is very good and you know noise and microphonics will be good……buying any RCA NOS these days is a gamble unless seller guarantees no noise and microphonics.
I am fixated by 2A3 sound. RCA 2A3 is to die for. I have 1971 date code and it opens up 8900 to another higher level of 3D soundstage. Don’t get me wrong Cossor/Linlai 2A3 is very good and you know noise and microphonics will be good……buying any RCA NOS these days is a gamble unless seller guarantees no noise and microphonics.
What 12au7 tubes and equivalents has anybody tried so far? I really like my RCA 12aU7 Cleartops and TungSol 12au7. Trying out Sylvania 6189 right now.
I use NOS ECC82 Tungsram and also NOS Mullard 12AU7. No experience with RCA clear top. In my system with easy listening mostly vocal music, both are great, Mullard gives slightly overall smoother presentation and bit more details slightly larger soundstage maybe. But Tungsram performs well for the money. This is driving RCA 2A3
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For 12au7 I have tried Mullard cv4003 box plates and Brimar 6067 T version I only ran each for a couple of hours as did not want to put lots of hours on them and that was in the first 25hrs both sounded good. 99% or time I've been listening with the Sylvanian 12bh7 over 200hrs so far so will be sure to try the 12au7 again. I've been wondering about using E80cc as have some very nice ones but have not checked the data sheets yet.
These are all good tubes 🙂 Let me add some others I have tried :
GE 5814A - nothing to brag about
Cifte 12au7 - reminds me of NOS Mullard 12au7
Mullard NOS CV4003/12au7 (Eico or Hammnd logo, found in organs) is probably the best with detail and adds some warmth to those bright systems.
RFT 12au7 - been a while since I heard these but I felt the soundstage decreased and lost detail
Bugle Boy 12au7 - this is one of the best 12au7 like the Mullard NOS but where the Mullard is detailed and warm, the Bugle Boy can be bright at times and mezmerizing with all the detail it brings out. Excels at 3d soundstage
Psvane 12au7 - this is a real sleeper, sounds probably 80% like a NOS Mullard but without the hefty price
Has anybody had any experience with rca grey vs black plates ?
GE 5814A - nothing to brag about
Cifte 12au7 - reminds me of NOS Mullard 12au7
Mullard NOS CV4003/12au7 (Eico or Hammnd logo, found in organs) is probably the best with detail and adds some warmth to those bright systems.
RFT 12au7 - been a while since I heard these but I felt the soundstage decreased and lost detail
Bugle Boy 12au7 - this is one of the best 12au7 like the Mullard NOS but where the Mullard is detailed and warm, the Bugle Boy can be bright at times and mezmerizing with all the detail it brings out. Excels at 3d soundstage
Psvane 12au7 - this is a real sleeper, sounds probably 80% like a NOS Mullard but without the hefty price
Has anybody had any experience with rca grey vs black plates ?
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