crtexcnndrm99 Posted August 8, 2020 Share Posted August 8, 2020 Not compete, but close enough for a listen tonight (finally) 7 Link to comment Share on other sites More sharing options...
Red MacKay Posted August 8, 2020 Share Posted August 8, 2020 31 minutes ago, SumonKabir said: Finally DHT preamp is now complete Great stuff Simon! What is the rectifier - some old 5 pin British thing? 4v? Certainly looks the goods! When do we get a report on the sound of a 4P1L DHT pre? Link to comment Share on other sites More sharing options...
Red MacKay Posted August 8, 2020 Share Posted August 8, 2020 33 minutes ago, crtexcnndrm99 said: Not compete, but close enough for a listen tonight (finally) What are the drivers used here please? That's a lot of hours in those cabinets! Jeez - all these people are gettin stuff built! Here I am in hard lockdown in Olde Melbourne Town and well - I'm getting nothing done... Well Done boys - keep building. 4 Link to comment Share on other sites More sharing options...
SumonKabir Posted August 8, 2020 Share Posted August 8, 2020 2 minutes ago, Red MacKay said: Great stuff Simon! What is the rectifier - some old 5 pin British thing? 4v? Certainly looks the goods! When do we get a report on the sound of a 4P1L DHT pre? Yes, Rectifier is Telefunken RGN1064 mesh plate. 4v. I am listening to this preamp for a month now. Not sure what to report. Vocal and piano is amazing. Very tight bass. Overall it feels like everything is so balanced. Something is very different to 6SN7 or ecc83. You need to try out yourself to find the magic. 1 Link to comment Share on other sites More sharing options...
crtexcnndrm99 Posted August 8, 2020 Share Posted August 8, 2020 5 minutes ago, Red MacKay said: What are the drivers used here please? That's a lot of hours in those cabinets! Jeez - all these people are gettin stuff built! Here I am in hard lockdown in Olde Melbourne Town and well - I'm getting nothing done... Well Done boys - keep building. Thanks mate - yes I don’t know if I’d have started them if I had been aware of how time consuming it was..! Drivers are Beyma 15AX38Nd. 15” coaxials. I’m pretending they’re Altec 604s it Tannoy MG15 because I don’t have the dough for either of those Argh it’s rough situation, I hope lockdown is an opportunity for you to enjoy the main part - the music! 2 Link to comment Share on other sites More sharing options...
mwhouston Posted August 8, 2020 Share Posted August 8, 2020 1 hour ago, crtexcnndrm99 said: Not compete, but close enough for a listen tonight (finally) Could we have some more detailed images of the speakers? 1 Link to comment Share on other sites More sharing options...
Red MacKay Posted August 8, 2020 Share Posted August 8, 2020 10 minutes ago, SumonKabir said: Yes, Rectifier is Telefunken RGN1064 mesh plate. 4v. I am listening to this preamp for a month now. Not sure what to report. Vocal and piano is amazing. Very tight bass. Overall it feels like everything is so balanced. Something is very different to 6SN7 or ecc83. You need to try out yourself to find the magic. An old Telefunken - nice. What - you have had it going for a month - and only now you are telling us! I have a 10Y DHT in my system. I have mine setup to run 5v rectifiers. So I can use 80, GZ30, GZ32, GZ34, 5AS4, 5R4, 5U4G, U52 etc. The two standouts are the 80 and the GZ30. Just this morning I fitted an octal socket with a couple of diodes fitted. Wow - better detail and bass, but after 8hrs of it - it was splitting my head. Of course the volts would have been higher and this might be the reason for the headsplitting as I found around 200v was the sweet spot in this configuration. So back in with the old 80. Ahhh - not as 'clean' and the bass is not so tight, but the music has that beautiful flow again. I have a couple of old globe 80s somewhere - I might see if I can find that and try it. 1 Link to comment Share on other sites More sharing options...
mwhouston Posted August 8, 2020 Share Posted August 8, 2020 25 minutes ago, crtexcnndrm99 said: Thanks mate - yes I don’t know if I’d have started them if I had been aware of how time consuming it was..! Drivers are Beyma 15AX38Nd. 15” coaxials. I’m pretending they’re Altec 604s it Tannoy MG15 because I don’t have the dough for either of those Argh it’s rough situation, I hope lockdown is an opportunity for you to enjoy the main part - the music! This was my more simpler build of those drivers. Since sold. They are very impressive. https://retro-thermionic.blogspot.com/2016/03/voxgrandious-beyma-high-efficiency-15.html Link to comment Share on other sites More sharing options...
RankStranger Posted August 8, 2020 Share Posted August 8, 2020 16 minutes ago, mwhouston said: Could we have some more detailed images of the speakers? good pics in the build thread Link to comment Share on other sites More sharing options...
SumonKabir Posted August 8, 2020 Share Posted August 8, 2020 (edited) 29 minutes ago, Red MacKay said: An old Telefunken - nice. What - you have had it going for a month - and only now you are telling us! I have a 10Y DHT in my system. I have mine setup to run 5v rectifiers. So I can use 80, GZ30, GZ32, GZ34, 5AS4, 5R4, 5U4G, U52 etc. The two standouts are the 80 and the GZ30. Just this morning I fitted an octal socket with a couple of diodes fitted. Wow - better detail and bass, but after 8hrs of it - it was splitting my head. Of course the volts would have been higher and this might be the reason for the headsplitting as I found around 200v was the sweet spot in this configuration. So back in with the old 80. Ahhh - not as 'clean' and the bass is not so tight, but the music has that beautiful flow again. I have a couple of old globe 80s somewhere - I might see if I can find that and try it. I tried 5y3, 5u4g and 5AR4. But Telefunken 1064 mesh sounds better in my ears. Or I like the glow in the dark Edited August 8, 2020 by SumonKabir Spelling mistake Link to comment Share on other sites More sharing options...
Red MacKay Posted August 8, 2020 Share Posted August 8, 2020 "Sounds better to my ears". Indeed - that is where it is. Link to comment Share on other sites More sharing options...
SumonKabir Posted August 8, 2020 Share Posted August 8, 2020 (edited) 33 minutes ago, Red MacKay said: An old Telefunken - nice. What - you have had it going for a month - and only now you are telling us! I have a 10Y DHT in my system. I have mine setup to run 5v rectifiers. So I can use 80, GZ30, GZ32, GZ34, 5AS4, 5R4, 5U4G, U52 etc. The two standouts are the 80 and the GZ30. Just this morning I fitted an octal socket with a couple of diodes fitted. Wow - better detail and bass, but after 8hrs of it - it was splitting my head. Of course the volts would have been higher and this might be the reason for the headsplitting as I found around 200v was the sweet spot in this configuration. So back in with the old 80. Ahhh - not as 'clean' and the bass is not so tight, but the music has that beautiful flow again. I have a couple of old globe 80s somewhere - I might see if I can find that and try it. Solder looks so neat. Damn. Never thought about this option for trial. Would give it a go, I may have some Crees somewhere to try out. Not sure 400v rating though. Edited August 8, 2020 by SumonKabir Link to comment Share on other sites More sharing options...
SumonKabir Posted August 8, 2020 Share Posted August 8, 2020 Point to point Travish phono in progress 1 Link to comment Share on other sites More sharing options...
mwhouston Posted August 8, 2020 Share Posted August 8, 2020 1 hour ago, mwhouston said: Could we have some more detailed images of the speakers? Still using my Xovers? Link to comment Share on other sites More sharing options...
Steffen Posted August 8, 2020 Share Posted August 8, 2020 2 hours ago, Red MacKay said: Just this morning I fitted an octal socket with a couple of diodes fitted. Wow - better detail and bass, but after 8hrs of it - it was splitting my head. Of course the volts would have been higher and this might be the reason for the headsplitting as I found around 200v was the sweet spot in this configuration. Interesting. I wonder whether you could emulate the lossy tube rectifier by bridging the diodes with a suitably sized resistor. 1 Link to comment Share on other sites More sharing options...
crtexcnndrm99 Posted August 8, 2020 Share Posted August 8, 2020 8 hours ago, RankStranger said: good pics in the build thread Yep and I should have added more pics yesterday, but I went nuts on the bracing so it’s not very good eye candy. Link to comment Share on other sites More sharing options...
crtexcnndrm99 Posted August 8, 2020 Share Posted August 8, 2020 7 hours ago, mwhouston said: Still using my Xovers? Yes, they’ve been so easy to use so thank you. Interested if you can make a pair with the optimal Xover you mentioned though. 1st order 1100.?. When you have the time 1 Link to comment Share on other sites More sharing options...
aussievintage Posted August 8, 2020 Share Posted August 8, 2020 7 hours ago, SumonKabir said: Point to point Travish phono in progress Yep, that's the way to do it. Separate passive eq filters between gain stages. I bet it will sound great. Well done 1 Link to comment Share on other sites More sharing options...
mwhouston Posted August 9, 2020 Share Posted August 9, 2020 2 hours ago, crtexcnndrm99 said: Yes, they’ve been so easy to use so thank you. Interested if you can make a pair with the optimal Xover you mentioned though. 1st order 1100.?. When you have the time Yes sure. Have some of the parts. I like to use the 4uf Russian PIO caps. Cheap and very effective. And wind my own chokes. I’ll PM you a quote. Link to comment Share on other sites More sharing options...
rewindhifi Posted August 10, 2020 Share Posted August 10, 2020 Building a PSU for Mac mini in a mini-itx case for $40 on ebay, and the mini-itx PSU going to a replacement power supply for a faulty ReadyNAS. Talking about kill 2 birds with one stone. 1 Link to comment Share on other sites More sharing options...
mwhouston Posted August 14, 2020 Share Posted August 14, 2020 My wife says they are breading. A collection of all DIY phono preamps, preamps (BoZ) and MC stages. 2 Link to comment Share on other sites More sharing options...
mwhouston Posted August 14, 2020 Share Posted August 14, 2020 (edited) I built this many moons ago. It’s a chip based two stage preamp with volume and balance control. But moving mainly to tube preamps it has remained used for many years. Now only requiring a single input from a BT receiver in my system 2 (mainly used for background music) ive re-chipped it and put it in play. It takes the place of a very nice BoZ I’ve been using for some time. Fortunately uses the same well filtered linear PS. Usually I use OPA2134s in anything with chips but occasionally LM833s. Looking through my chip draw I found a pair of TL072CNs and after looking at the spec sheets realise it can be dropped in where OPAs have been. The preamp is playing now and very surprised the preamp sounds bright and crisp. Glad I bought this out of retirement. A stack of gain and balance is easy to use and has a nice central wide spot. Extremely impressed with the sound through my DIY 6L6 SE UL tube power amp. Has anyone else had experience with the TL072CN chip? If so I’d like to know. I have no idea when I bought them or what I paid. I see they are only $1 each on RS. https://html.alldatasheet.com/html-pdf/159243/STMICROELECTRONICS/TL072CN/15594/8/TL072CN.html Edited August 14, 2020 by mwhouston 1 Link to comment Share on other sites More sharing options...
aussievintage Posted August 14, 2020 Share Posted August 14, 2020 2 hours ago, mwhouston said: My wife says they are breading. A collection of all DIY phono preamps, preamps (BoZ) and MC stages. Not sure I approve of the way you are storing those box sets either 3 Link to comment Share on other sites More sharing options...
oohms Posted August 14, 2020 Share Posted August 14, 2020 I've moved from large horns + wide range drivers to proper 1 inch compression drivers - now it is an all Faital setup with HF108R on those QSC clone waveguides and 15PR400 crossed at about 1.2khz The treble is much better now and the woofers are capable of this crossover point, so the next step is integrating the horns into the cabinets 7 Link to comment Share on other sites More sharing options...
mwhouston Posted August 14, 2020 Share Posted August 14, 2020 I was thinking on buying a 15PR400 to go with my Altec 511B horns and FaitalPro compression drivers same as yours. Currently using Beyma 12” as the woofer on a Salt Cellar mono system. There is a DJCity store not far from home which stock the driver. Link to comment Share on other sites More sharing options...
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