Upfront Posted May 31, 2018 Share Posted May 31, 2018 Hey upfront going the TD mids down to around 50ish, haven’t landed the exact f3 but somewhere around that In ported setup and crossing over to subs for the low end. It’s going to be fully active setup, still working out the cross to tweeter but somewhere between 1100 and 1300 looks good from initial modelling without sacrificing to much SPL. Looking forward to this one! 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted May 31, 2018 Share Posted May 31, 2018 4 hours ago, hyper said: Hey upfront going the TD mids down to around 50ish, haven’t landed the exact f3 but somewhere around that In ported setup and crossing over to subs for the low end. IMVHO if you have subs, then put the TD10(M?) in a sealed box. 1 Link to comment Share on other sites More sharing options...
hyper Posted May 31, 2018 Share Posted May 31, 2018 IMVHO if you have subs, then put the TD10(M?) in a sealed box.Hey Dave,Definitely makes sense and I did consider that (and still might change my mind) however I did want the flexibility to use them in their own right without support of sub, if I wanted to use them with my recording rig as monitors .. but take your point! 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted May 31, 2018 Share Posted May 31, 2018 I've just never had any fun getting a ported box right, that's all Link to comment Share on other sites More sharing options...
hyper Posted May 31, 2018 Share Posted May 31, 2018 I've just never had any fun getting a ported box right, that's all [emoji6]Ha it certainly ain’t as forgiving [emoji4] 1 Link to comment Share on other sites More sharing options...
hyper Posted June 1, 2018 Share Posted June 1, 2018 The enclosure mates have arrived. Pics don’t do them justice amazingly well built drivers can’t wait to get some initial measurements done.. 1 Link to comment Share on other sites More sharing options...
Rob181 Posted June 1, 2018 Share Posted June 1, 2018 From everything I have read...a great speaker... Now if only the hook up wire connector was copper...sigh... 1 Link to comment Share on other sites More sharing options...
mwhouston Posted June 2, 2018 Share Posted June 2, 2018 (edited) Putting together a two stage tube preamp for another SNA member to drive his Holton power amp. I've used a turrent brd. and employed my birds nest wiring techniques. Makes for short a signal path but a nightmare to fault trace. The second stage is a cathode follower which will drive into 10K easy. The front end can accept any 12A?? tube but the back end should stay 12AU7 for drive capabilities. I've selected JJ 12AX7 up front for preamplification and a Psvane 12AU7 top of the range "T" series MKII gold pin for the driver tube. What I like about both tubes is tiny plates. Tiny plates = low microphonics. The inter-stage cap and output cap are Russian military PIO. These have always given a clean and balanced performance and aren't expensive. Resistors are metal film. All silver soldered. Sockets are ceramic with gold plated pins. Edited June 2, 2018 by mwhouston 1 Link to comment Share on other sites More sharing options...
Brucec Posted June 2, 2018 Share Posted June 2, 2018 Thanks for sharing this. Fantastic this preamp is coming together, it sounds like it’s going to be (and sound like) a work of art. Link to comment Share on other sites More sharing options...
Upfront Posted June 2, 2018 Share Posted June 2, 2018 The enclosure mates have arrived. Pics don’t do them justice amazingly well built drivers can’t wait to get some initial measurements done.. Will be interesting to see what you do with them mate. Link to comment Share on other sites More sharing options...
Guest Muon N' Posted June 2, 2018 Share Posted June 2, 2018 1 hour ago, mwhouston said: Putting together a two stage tube preamp for another SNA member to drive his Holton power amp. I've used a turrent brd. and employed my birds nest wiring techniques. Makes for short a signal path but a nightmare to fault trace. The second stage is a cathode follower which will drive into 10K easy. The front end can accept any 12A?? tube but the back end should stay 12AU7 for drive capabilities. I've selected JJ 12AX7 up front for preamplification and a Psvane 12AU7 top of the range "T" series MKII gold pin for the driver tube. What I like about both tubes is tiny plates. Tiny plates = low microphonics. The inter-stage cap and output cap are Russian military PIO. These have always given a clean and balanced performance and aren't expensive. Resistors are metal film. All silver soldered. Sockets are ceramic with gold plated pins. I can't see fault tracing being at all difficult there, nice work Link to comment Share on other sites More sharing options...
mwhouston Posted June 2, 2018 Share Posted June 2, 2018 5 hours ago, Muon N' said: I can't see fault tracing being at all difficult there, nice work I agree this one is better opened up than some others I've done. Generally point to point is all parts on a tag board and wire for the brd. I try to solder parts directly to the tube sockets. In some tube power amps this results in a real birds nest. With the turrent brds you can open it up a little more. I have a pair of two stage preamp modules I put together with no hookup wire at all. What I call component-2-component wiring. I'll put up an image. Link to comment Share on other sites More sharing options...
mwhouston Posted June 2, 2018 Share Posted June 2, 2018 (edited) This is not what I was thinking of to post but when it comes to short signal path a Pass BoZ built on itself is about a short a signal path as you can get. The build does include part of the PS. I was working a lot with early Linux at this stage both at work and at home. Linux was bragging how it was recursive, using and re-using code within itself. I thought why not build a preamp on itself. So here it is The two big brown polies are 10uf output caps. The low ESR caps on the back ensure a good steady voltage right at the amp. The jFets are super glued on the output caps. The heavy wire at the low ESR caps is 99.9% 0.7mm pure silver. A Melbourne Audio Club member heard the resulting preamp and bought it to drive one of my KT88 SE UL amps. http://mongreldogaudio.blogspot.com/2010/12/boz-on-cap-bozoac.html Edited June 2, 2018 by mwhouston Link to comment Share on other sites More sharing options...
mwhouston Posted June 2, 2018 Share Posted June 2, 2018 (edited) The completed preamp ran on three Lithium batteries (27V) with two selectable inputs and Alps blue Velvet pot with a 4oz solid brass knob. http://mongreldogaudio.blogspot.com/2010/12/boz-on-cap-bozoac_27.html Edited June 2, 2018 by mwhouston Link to comment Share on other sites More sharing options...
betocool Posted June 3, 2018 Share Posted June 3, 2018 Hey Mark, where do you get the PIO caps? Cheers, Alberto Link to comment Share on other sites More sharing options...
mwhouston Posted June 3, 2018 Share Posted June 3, 2018 1 hour ago, betocool said: Hey Mark, where do you get the PIO caps? Cheers, Alberto Generally just ebay. They usually are not expensive. I've always bought boxes of them at a time figuring it will save on postage. I actually have way too many so if you are just after a few lets know the values and I could post them too you. Some are vey big as you can see others small. Depends on capacity and voltage rating. I used 4uf large PIOs in my Beyma speakers Xover (1st order) for the tweeter section. Xover frequ. was 1100hz. I heard an instant jump in clarity. Also I used low voltage 4uf in one of my Mimic phono stages as the output caps. Extremely good sounding. Link to comment Share on other sites More sharing options...
mwhouston Posted June 3, 2018 Share Posted June 3, 2018 PS brd. for tube preamp. Choked HT and regulated filament voltage. Link to comment Share on other sites More sharing options...
Upfront Posted June 3, 2018 Share Posted June 3, 2018 The start of a pair of carbon fibre/paper machè composite horns.... 3 Link to comment Share on other sites More sharing options...
mwhouston Posted June 3, 2018 Share Posted June 3, 2018 26 minutes ago, Upfront said: The start of a pair of carbon fibre/paper machè composite horns.... Someone knows what they are doing. Link to comment Share on other sites More sharing options...
Upfront Posted June 3, 2018 Share Posted June 3, 2018 Someone knows what they are doing. Haha! I will soon. Link to comment Share on other sites More sharing options...
hyper Posted June 3, 2018 Share Posted June 3, 2018 The start of a pair of carbon fibre/paper machè composite horns.... Impressive mate, did you make the molds? Link to comment Share on other sites More sharing options...
hyper Posted June 3, 2018 Share Posted June 3, 2018 Will be interesting to see what you do with them mate. I’m up to my least favourite bit designing enclosures, dam I hate cad programs. I’ve started on the subs which will test my patience a little less [emoji4] once I get the enclosure design done things will hopefully move abit quicker!! 1 Link to comment Share on other sites More sharing options...
Upfront Posted June 3, 2018 Share Posted June 3, 2018 Impressive mate, did you make the molds?Yep. Molded directly from one of Martins 550hz Azurahorns. It's been a long running event. I have a purely paper horn with a pair of Radian 950 drivers running with a pair of peerless 8" Nomex cone drivers and thinking of using something larger. Hence the interest in your project. Link to comment Share on other sites More sharing options...
hyper Posted June 3, 2018 Share Posted June 3, 2018 Yep. Molded directly from one of Martins 550hz Azurahorns. It's been a long running event. I have a purely paper horn with a pair of Radian 950 drivers running with a pair of peerless 8" Nomex cone drivers and thinking of using something larger. Hence the interest in your project. Nice work!! azurahorns, that’s the guy over in Perth right? What do you think of the radian comp drivers? Never tried em, always wanted to Link to comment Share on other sites More sharing options...
Upfront Posted June 3, 2018 Share Posted June 3, 2018 Nice work!! azurahorns, that’s the guy over in Perth right? What do you think of the radian comp drivers? Never tried em, always wanted toThanks mate. Yes Martin in Perth. Very nice guy. Very clever. Very nice horns too! Love the Radians. Lots of detail. Couldn't be happier. So much so, I have a couple more horns in the works for them. Link to comment Share on other sites More sharing options...
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