Mushroom01 Posted April 15, 2020 Share Posted April 15, 2020 I've just completed a new speaker build this morning. Stand mount/Book shelf. 18mm Hardwood Ply, damped with heavy wool carpet + egg crate foam. PU expanding glue, no screws. Beeswax finish - no stain, natural wood colour. Tang Band 8 ohm W3-1364S. Sealed in 1L enclosure. Peerless 8 ohm HDS-P835025. Vented 18L, tuned to 50 Hz. Xover - custom First order solen split - Jantzen caps & inductors. Xover point 800-900 Hz. Zobel on both drivers. Front panel sprayed with pressure pack, Flat Iron colour. 5 Link to comment Share on other sites More sharing options...
mwhouston Posted April 15, 2020 Share Posted April 15, 2020 27 minutes ago, Mushroom01 said: I've just completed a new speaker build this morning. Stand mount/Book shelf. 18mm Hardwood Ply, damped with heavy wool carpet + egg crate foam. PU expanding glue, no screws. Beeswax finish - no stain, natural wood colour. Tang Band 8 ohm W3-1364S. Sealed in 1L enclosure. Peerless 8 ohm HDS-P835025. Vented 18L, tuned to 50 Hz. Xover - custom First order solen split - Jantzen caps & inductors. Xover point 800-900 Hz. Zobel on both drivers. Front panel sprayed with pressure pack, Flat Iron colour. I’ve felt in the past zobels have flattened dynamics. If it’s easy enough try with and without. Looks good but! Like the iron colour. Link to comment Share on other sites More sharing options...
Mushroom01 Posted April 15, 2020 Share Posted April 15, 2020 2 minutes ago, mwhouston said: I’ve felt in the past zobels have flattened dynamics. If it’s easy enough try with and without. Looks good but! Like the iron colour. Thanks for the tip! I didn't know that was possible. Xover is removable, so i could try with/without. 1 Link to comment Share on other sites More sharing options...
planet10 Posted April 15, 2020 Share Posted April 15, 2020 I am a big fan of WAW. Good work, love to see more & more of them popping up Is that W8-1772 or 1808? I have a pair of the little TB with the cyclindrical phase plug, found them quite colourful. And foam is not a very good dampin gmaterial IME. dave 1 Link to comment Share on other sites More sharing options...
Mushroom01 Posted April 15, 2020 Share Posted April 15, 2020 14 minutes ago, planet10 said: I am a big fan of WAW. Good work, love to see more & more of them popping up Is that W8-1772 or 1808? I have a pair of the little TB with the cyclindrical phase plug, found them quite colourful. And foam is not a very good dampin gmaterial IME. dave Thanks Dave. 1808, sealed into 24L. I really enjoy the signature sound of the TB drivers. To me the vocals, brass, piano & string instruments sound spectacular! I want to try the MA drivers one day, as I've not listed to these yet. I have the Frugal Horn XL plan I purchased about 4 years ago, but haven't built them yet. Link to comment Share on other sites More sharing options...
planet10 Posted April 15, 2020 Share Posted April 15, 2020 24 minutes ago, Mushroom01 said: 1808, sealed into 24L. ...Frugal Horn XL ... I prefer 1808 to the 1772, but i figure both are too pricey for what you get. Do build the FHXL, you will add to the estimated 10k FH builds so far. I have to get Alpair 11ms into my FHXL, and a set of A7ms into one of my FH3s. Is your misspelling of Frugel due to auto-correct?sometimes it drives me crazy, i am a bad typer (took Grade 11 math instead of Grade 10 typinf thinkin gi would never need to do any typing and i get some wild sentences. dave 1 Link to comment Share on other sites More sharing options...
Mushroom01 Posted April 15, 2020 Share Posted April 15, 2020 15 minutes ago, planet10 said: Is your misspelling of Frugel due to auto-correct?sometimes it drives me crazy, i am a bad typer (took Grade 11 math instead of Grade 10 typinf thinkin gi would never need to do any typing and i get some wild sentences. Yep, bloody auto correct. My friend has the much cheaper W8-2145. It's very very close to the 1808 in performance. Good value imo. 1 Link to comment Share on other sites More sharing options...
mwhouston Posted April 20, 2020 Share Posted April 20, 2020 Should you be inspired to make an OPA2134 based project element14 have genuine chips (at least according to the image) for $74 for ten. Also I bought their top of the range 8 pin sockets for $14 for ten. There are cheaper quality sockets for the sale but for a few dollars I went for the best. I wouldn’t buy from eBay suppliers because there are so many fakes these days. Stick with respected companies. I usually buy from RS but they are out of stock. 1 Link to comment Share on other sites More sharing options...
mwhouston Posted April 21, 2020 Share Posted April 21, 2020 Don’t know about you but I get my inspiration to build from all sorts of strange places. First by accident I came across this schematic for E88CCs which I have a matched pair of Gold Lion gold pins. I’d bought these for someone who bought one of my early tube preamps and they wanted to upgrade the tubes. But when the tubes arrived they changed their mind. I got stuck with them. Then while looking for spray paint (cans of which I have many) for my wife to spray a stool I came across this can of Deep Indian Red which I had only ever used on one project for another. At the time I though I’d like to use this colour for a new project. Then it hit me, the schematic, the tubes and now the paint. I also had a new spare Hammond chassis which I’d had for a while and most other parts including a pile of RCAs and ceramic sockets. Another quarentinie project? You bet! And a chance to use up parts which have been lying around for years. I already have my universal PS which serves a few other tube preamps. Chassis has been drilled and etch primed. Now for that Deep Indian Red top coat. In two days I can assemble. 2 1 Link to comment Share on other sites More sharing options...
Red MacKay Posted April 21, 2020 Share Posted April 21, 2020 For me it's no so much inspiration - more frustration with myself cos I'm so lazy. I start all enthusiastic, collect all the parts bar one or two and then it all gets too hard and I just move to the next and do the same with that. Sound familiar... But a couple of months back at an audio buddy's place (before draconia kicked in) I heard something (a diy Jean Hirage 30w ClassA) that challenged a couple of my treasured audio 'sacred cows'. Well, ..."If you can't beat them - join them." The Hirage's such a simple circuit and with quality driver and output kits so readily available from Jim's Audio - even an electronics novice like me can have a crack at it. As everyone knows I have started this, there is no way I can duck my way out now! A good thing really. 2 Link to comment Share on other sites More sharing options...
mwhouston Posted April 21, 2020 Share Posted April 21, 2020 Just before I build this can anyone see anything very wrong with the schematic. I’m not looking for suggestions of any other cct. I have plenty but want to know if there is something really wrong with this. Ta! Link to comment Share on other sites More sharing options...
planet10 Posted April 21, 2020 Share Posted April 21, 2020 That is Frank’s map that i recently posted. A decent circuit, can be finessed by adding a CCS on the top of the CC, and on the bottom of the CF. dave Link to comment Share on other sites More sharing options...
aussievintage Posted April 21, 2020 Share Posted April 21, 2020 (edited) 2 hours ago, mwhouston said: Just before I build this can anyone see anything very wrong with the schematic. I’m not looking for suggestions of any other cct. I have plenty but want to know if there is something really wrong with this. Ta! Not that I do it every time, but, are you aware of the problem at startup where the grid of the cathode follower gets exposed to full HT before it warms up and can result in arcing and damage? There is a mod with a diode and resistor from grid to cathode to help with this. Also, I don't like muting by shorting the AC output of the valve to ground ! Maybe a changeover switch that disconnects the output and then connects the output socket it to ground leaving the the valve working into a bit less than 20K impedance. Don't know if you like cathode bypassing, but the first stage could obtain a little more gain if you do. Edited April 21, 2020 by aussievintage Link to comment Share on other sites More sharing options...
r3x Posted April 21, 2020 Share Posted April 21, 2020 Consider the ac operating conditions of the cathode follower with the mute switch closed. 1 Link to comment Share on other sites More sharing options...
aussievintage Posted April 21, 2020 Share Posted April 21, 2020 Also, grid stoppers would be a good idea. Link to comment Share on other sites More sharing options...
mwhouston Posted April 21, 2020 Share Posted April 21, 2020 I would never put the switch in. Thanks for the good suggestions so far. Ive built this before. Would this be better? I know is sounds really good. Link to comment Share on other sites More sharing options...
mwhouston Posted April 21, 2020 Share Posted April 21, 2020 4 hours ago, planet10 said: That is Frank’s map that i recently posted. A decent circuit, can be finessed by adding a CCS on the top of the CC, and on the bottom of the CF. dave CCS, not gunna appen. But Ta regardless! Link to comment Share on other sites More sharing options...
aussievintage Posted April 21, 2020 Share Posted April 21, 2020 1 minute ago, mwhouston said: CCS, not gunna appen. But Ta regardless! I don't bother either. I know what they say, but there are more important things. Link to comment Share on other sites More sharing options...
mwhouston Posted April 22, 2020 Share Posted April 22, 2020 The Epoxy Enamel can said “Deep Indian Red”. It may dry, over the next few days, a little lighter but to me it’s more a chocolate brown. Link to comment Share on other sites More sharing options...
aussievintage Posted April 22, 2020 Share Posted April 22, 2020 Hard to tell without calibrated monitors and corrected white balance. Did you want this Indian red ?? I wouldn't mind one 2 1 Link to comment Share on other sites More sharing options...
mwhouston Posted April 22, 2020 Share Posted April 22, 2020 It’s just a poor description of a colour. I sort of like it. Not every chassis has to be black. Link to comment Share on other sites More sharing options...
mwhouston Posted April 22, 2020 Share Posted April 22, 2020 9 minutes ago, aussievintage said: Hard to tell without calibrated monitors and corrected white balance. Did you want this Indian red ?? I wouldn't mind one The Oz version of this bike is called the “Indigenous”. Link to comment Share on other sites More sharing options...
aussievintage Posted April 22, 2020 Share Posted April 22, 2020 1 minute ago, mwhouston said: It’s just a poor description of a colour. I sort of like it. Not every chassis has to be black. Yeah, I think it does look good. 1 Link to comment Share on other sites More sharing options...
aussievintage Posted April 22, 2020 Share Posted April 22, 2020 Today's small project was to give this baby amp a new lease of life. I believe I have mentioned this amp here before, but anyway here it is as it currently looks with a photo. It was one of the first SET amps I built years ago. It uses a 6DJ8 dual triode as a driver, half on each channel, and 6AQ5 power valves - well a 6005W ruggedised version. These are miniature 7 pin versions of the 6V6 you often see used in guitar amps (and some hifi). They are wired as triodes and with the current power supply etc. they might struggle to put out as much as 2 watts on a good day. I pulled it out of storage and cleaned up everything including the valve sockets and pins. I have put it in my office system with some inefficient Dick Smith bookshelf speakers, but it has plenty of power for this use. Still sounds as good as my recollection told me it did. I just got wooed by the praise of popular valves used in things like the 2A3 SET amps at that time. 2 Link to comment Share on other sites More sharing options...
mwhouston Posted April 22, 2020 Share Posted April 22, 2020 Don’t knock 2W with the right speakers there’s plenty of tubey volume. My 6L6 SE UL Silver Supreme and 98db sensitive Beyma concentrics (currently in my main system) deliver plenty of volume. And dead quiet operation. https://retro-thermionic.blogspot.com/2017/02/silver-supreme-6l6-se-ul-amp-in-wooden.html https://retro-thermionic.blogspot.com/2014/07/voxconcentric-beyma-12-high-efficiency.html Link to comment Share on other sites More sharing options...
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