acg Posted November 6, 2019 Author Share Posted November 6, 2019 I had a client like that/me. The scope of the (large) project kept getting bigger, more complex, and troublesome and eventually we had a falling out over it. Me: You can't just keep shifting the finish line every couple of months, it's a waste of my time. Client: Just get it done already, you are costing me too much. He didn't stop and I couldn't hit that moving target. 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 6, 2019 Share Posted November 6, 2019 On 18/10/2019 at 11:37 AM, acg said: They are Kong at killing reverberations but from what I can figure out may not impact the room frequency response too much. It depends on how you measure it Link to comment Share on other sites More sharing options...
acg Posted November 6, 2019 Author Share Posted November 6, 2019 15 minutes ago, davewantsmoore said: It depends on how you measure it Care to elaborate Dave? Link to comment Share on other sites More sharing options...
acg Posted November 6, 2019 Author Share Posted November 6, 2019 4 hours ago, Grizzly said: I absolutely love that Ortofon chose to make something that could easily be referred to as MC Hammer. Doesn't sound like one though... Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 7, 2019 Share Posted November 7, 2019 19 hours ago, acg said: Care to elaborate Dave? They're problem doing a lot more than you think, if you look at the LF with a higher frequency resolution and/or a finer scale of dB. Typical "frequency response" measurements are not very useful, IMVHO. Link to comment Share on other sites More sharing options...
acg Posted November 7, 2019 Author Share Posted November 7, 2019 41 minutes ago, davewantsmoore said: They're problem doing a lot more than you think, if you look at the LF with a higher frequency resolution and/or a finer scale of dB. Typical "frequency response" measurements are not very useful, IMVHO. Dave, are there ways to look at LF with a higher frequency resolution? The lowest strings of a double bass, bass guitar or even a cello tends to hit a room mode right where I stand at my desk. It is really distracting, and if a VPR or two can be used to reduce that effect I will be very happy. I've never had bass as soft or textured or powerful as I have it now with the Bass Cannons and room modes are very easy to find just walking about the room. The listening chair seems to be the best spot for bass because it is right in the middle of the axial walls and I have the windows directly behind me letting plenty of LF out of the room. Regarding the VPR's, I should get in and order some foam so I am ready to make them up at Christmas. 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 7, 2019 Share Posted November 7, 2019 43 minutes ago, acg said: Dave, are there ways to look at LF with a higher frequency resolution? Longer measurement window, but it comes with it's own problems. The real thing is, is the steady state response of the room worth looking at in this regard. For levels, it is perhaps (and levels are very sensitive, eg. +/- a dB or two at 50Hz vs 100Hz can be massive) ... but otherwise I would be looking at the data in other ways. Waterfalls, ETC, wavelet, etc.... and with other test signals. Although aside from finding really specific problems, then even that might be not too useful. You just can't really have too much "treatment" at LF. The only challenge is fitting it in, and keeping it even with the HF. 43 minutes ago, acg said: I've never had bass as soft or textured This is typically what happens when you have an even frequency response which doesn't have any extreme peaks or cancellations. Peaks of even a few dB drown out everything as they sound so much louder than everything else (a few dBs is a lot in the bass for perception of loudness) .... once you get rid of all the "drowning out", and all the "gone missing" .... then bass can have incredible "texture". Link to comment Share on other sites More sharing options...
acg Posted November 23, 2019 Author Share Posted November 23, 2019 What I love about modern valve amplifier builds is the possibility and benefits of mixing old and new technologies. Lately, I've been sneaking an hour here and there to advance the electronics projects and have managed a few small milestones. Have a look at the photo below... That is the RIAA correction filter for one channel of my upcoming LCR phonostage. Two handsome Slagle inductors on mumetal cores, some Jupiter copper foil caps and some custom cut TX2575 Z-foil resistors that should make a frequency response flat line out of the very wobbly riaa cut of the records. It all sits on a 4mm thick aluminium plate that in turn sits inside an off-the-shelf EMI/RFI box which in turn will sit inside a 4mm thick steel sarcophagus in an effort to maintain a very low noise floor in the circuit. It sits between a pentode first stage and triode second stage. So, above is a nice example of the old-school purists method of sacrificing resources and real-estate with rats-nest wiring. So the tubes have to be supplied 6.3vdc and I had alook through my pcb box to find a challenging build using paralleled LT3042 ultralow noise LDO's. These things are tiny...0.5mm pitch MSOP. I've never soldered them before so decided to order the parts and give the little psu a go. See below, it worked... That green pcb has two 6.3V 1A power supplies including all rectifier diodes, filter caps and heat sinking (later two items under the board). I hand-soldered the little bugger and it took a couple of hours but it worked first time! Those big (haha) yellow 1205 caps make the LT3042 look tiny. What is not shown is that little green pcb is going to be connected to two relatively huge EI filament transformers. Anyway, that is my rather extreme example of modern and vintage electronics used in the same component, a RIAA phonocorrector. Can't wait to get it finished. 2 Link to comment Share on other sites More sharing options...
Ian McP Posted December 17, 2019 Share Posted December 17, 2019 simply awesome! 4 Link to comment Share on other sites More sharing options...
acg Posted December 18, 2019 Author Share Posted December 18, 2019 How interesting! Thanks @Ian McP Seems a similar trajectory to mine... 3 Link to comment Share on other sites More sharing options...
almikel Posted December 19, 2019 Share Posted December 19, 2019 On 19/12/2014 at 5:39 PM, acg said: So, something turned up the other day. Whatever could it be for? A Christmas project perhaps... wow - just noted today is 19 Dec - happy epic DIY project thread anniversary day !!! Anthony you are an inspiration. Maintaining the drive and vision for 5 years is phenomenal - well done... ...and getting very close to completion...I won't ask "which Christmas?" Easily the most ambitious DIY project I've seen, and tracking progress from inception to today has been both enjoyable and informative. Thanks for including us in your journey! cheers Mike 4 Link to comment Share on other sites More sharing options...
davewantsmoore Posted December 19, 2019 Share Posted December 19, 2019 7 hours ago, almikel said: wow - just noted today is 19 Dec - happy epic DIY project thread anniversary day !!! The "in by Xmas?!!" joke is still funny every year too (Seconded). 2 Link to comment Share on other sites More sharing options...
acg Posted December 21, 2019 Author Share Posted December 21, 2019 On 19/12/2019 at 2:16 PM, almikel said: ...and getting very close to completion...I won't ask "which Christmas?" Maybe next Christmas... Although stuff is still getting done. The plan, assuming the temperature is bearable in that little tin shed, is to get back on the lathe next week or so to sort out the front half of the upperbass horns. 1 Link to comment Share on other sites More sharing options...
almikel Posted December 21, 2019 Share Posted December 21, 2019 4 hours ago, acg said: Although stuff is still getting done. that's the impressive bit - there's been inexorable progress towards the end goal, with no compromise on vision. As a lazy DIYer I remain in awe of your commitment...it will be finished when it's finished...the elephant will be eaten...completely (please excuse the metaphor if you're a vegetarian). cheers Mike 1 Link to comment Share on other sites More sharing options...
VAKMAN Posted December 28, 2019 Share Posted December 28, 2019 M Link to comment Share on other sites More sharing options...
acg Posted January 23, 2020 Author Share Posted January 23, 2020 Small steps... So, finally, the shelf bass traps are complete and in place. They were done in fits and starts but we got there in the end. I love having them in the room with the cane facing and the lovely wood tops...the room feels nicer to be in just for their presence. The vinyl flips have also worked out well, here's one with the lid up to show how they work. Will have to resist the urge to treat them just like a normal shelf and just load the top of them up with "stuff" but it is a handy place to put the tablet that controls digital playback. Talking about digital, Mark Dohmann was here last night and he did the "in-house" final setup of the Helix2/MC Anna for me. What a pleasure to meet the man in person and what great service. We stayed up well past my bedtime listening to various curiosities from Talk Talk among others and finished with a nasty old John Lee Hooker record. What has that got to do with digital? Well, nothing really, but the little 1's and 0's have just been o.w.n.e.d. 5 Link to comment Share on other sites More sharing options...
acg Posted January 23, 2020 Author Share Posted January 23, 2020 Oh yeah, and two pair of replacement horns ready to go onto the stack... 7 Link to comment Share on other sites More sharing options...
Mat-with-one-t Posted February 20, 2020 Share Posted February 20, 2020 What happens next!? What happens next! ?.?? Link to comment Share on other sites More sharing options...
realysm42 Posted April 2, 2020 Share Posted April 2, 2020 On 20/02/2020 at 10:09 PM, Mat-with-one-t said: What happens next!? What happens next! ?.?? This. Link to comment Share on other sites More sharing options...
Mat-with-one-t Posted April 2, 2020 Share Posted April 2, 2020 2 hours ago, realysm42 said: This. Bit of an anti climax..... Link to comment Share on other sites More sharing options...
acg Posted April 4, 2020 Author Share Posted April 4, 2020 (edited) Yeah guys, sorry, no time for audio with only one day off work so far this year, even with this pandemic. Crazy busy, but nice to be so right now. Might be able to start taking the odd weekend off in a month or so...perhaps...I doubt anybody will be travelling anywhere for leisure this side of spring or even summer so those weekends will probably translate into audio progress. The system will be finished, just not quickly. Edited April 4, 2020 by acg 2 Link to comment Share on other sites More sharing options...
acg Posted July 26, 2020 Author Share Posted July 26, 2020 Amplifier #2 is alive... Stereo sound here I come!! Had a week at the coast earlier this month and managed to unwind enough to think about audio again. The fix for the biasing problem just came to me even though I had not thought about it since Christmas, and yesterday I just got the fix done. It was so simple and I am kinda embarassed that I was not able to find the issue more easily, but it is done now!! A week to soak in on the electronics bench (make sure it does not start any fires...haha) then I'll have to find a couple of strong guys to help me heft it upstairs and into place. Can't wait!! 6 Link to comment Share on other sites More sharing options...
acg Posted July 30, 2020 Author Share Posted July 30, 2020 Impatience got the better of me, and I called two mates who promptly showed up yesterday afternoon and we hefted the second DSET into place on the horn stack. A couple of hours of connecting and checking things and it was ready to fire up for my first stereophonic sound in 18 months. What a delight! Even with a dying 45 in the right channel and a sweet YO18 in the left! Especially with the lovely Helix Two/Schroder CB/MC Anna in action. You'll also notice the tv on the front wall...yes, I vowed no television upstairs but have buckled and am actually quite enjoying its quality. Of course this also means home theatre and all that entails....plenty of more stuff to think about. So, just when I get that monolith off the electronics bench downstairs, I also have the final transformers, chokes and filament supplies for the forthcoming DHT Preamp and LCR Phonostage finally en-route. Perfect timing. So lathe work to actually finish the upperbass horn is the first order of business in parallel with preamplifier, phono and room treatment. Still plenty to do! 5 Link to comment Share on other sites More sharing options...
Tax Posted July 31, 2020 Share Posted July 31, 2020 On 30/07/2020 at 2:19 PM, acg said: Impatience got the better of me, and I called two mates who promptly showed up yesterday afternoon and we hefted the second DSET into place on the horn stack. A couple of hours of connecting and checking things and it was ready to fire up for my first stereophonic sound in 18 months. What a delight! Even with a dying 45 in the right channel and a sweet YO18 in the left! Especially with the lovely Helix Two/Schroder CB/MC Anna in action. You'll also notice the tv on the front wall...yes, I vowed no television upstairs but have buckled and am actually quite enjoying its quality. Of course this also means home theatre and all that entails....plenty of more stuff to think about. So, just when I get that monolith off the electronics bench downstairs, I also have the final transformers, chokes and filament supplies for the forthcoming DHT Preamp and LCR Phonostage finally en-route. Perfect timing. So lathe work to actually finish the upperbass horn is the first order of business in parallel with preamplifier, phono and room treatment. Still plenty to do! Love it! I see there has been some traction since our call Link to comment Share on other sites More sharing options...
acg Posted August 1, 2020 Author Share Posted August 1, 2020 @Tax, sure has mate. Was cooking breakfast this morning on the barbecue when a courier came in and dropped off my transformer packages from Black Art Audio. Woo hoo! Was going to work today but I reckon I might breadboard together a DHT preamp instead. 1 Link to comment Share on other sites More sharing options...
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