I don't know if this is true for all of class D but it certainly is for my ICEpower amps. I know they will be skeptical, but I have talked to other audiophiles who have found the same issues: The amps sound poor until left on for over 2 days. You don't have to play music, or listen continuously so it's not a matter of your ears being reset. I only learned of this after leaving the power off for two days due to storms and being away from home. My current A/B amps have no such issue, nor do I detect this in my Hypex powered center channel which has auto on/off.
Hi, my icepower amps sound fine as soon as power switch is flicked on, all the day until I switch it off. If I turn it back on, the sound is still the same. It's good amplifier that wprks as it should, is silent and has lots of power for home use and has no quirks like warm up period. Just to provide another perspective.
It's tpa3255 chip based icepower amp, and they have all kinds off implementations of power amplifiers, so, "icepower amp" is not very precise term. While amplifier sound changes with time until temperature /operation stabilizes, it really isn't obvious on my icepower amps. Perhaps on some other amplifiers it is, in general. My amps have quite bad efficiency with low power use and consume enough power it is advantageous to shut the system down when not listening. Three idling amplifiers draw 20watts or so.
It's tpa3255 chip based icepower amp, and they have all kinds off implementations of power amplifiers, so, "icepower amp" is not very precise term. While amplifier sound changes with time until temperature /operation stabilizes, it really isn't obvious on my icepower amps. Perhaps on some other amplifiers it is, in general. My amps have quite bad efficiency with low power use and consume enough power it is advantageous to shut the system down when not listening. Three idling amplifiers draw 20watts or so.
Sorry but I'm confused. ICEpower is a brand which I believe is owned by B&O, while TPA is a Texas Instrument chip. The two brands I believe are competitors. Are you confusing ICEpower with Class D or am I mistaken?
In particular I used ICEpower 250ASP amps. Still have them, probably going to use them to make more DSP crossed speakers. 🙂
As I mentioned before, I don't seem to have the same issue with Hypex but the plate amp I use seems to run hotter than my ASPs do when on.
I have ICEpower 200as2 amps, they are with TPA3255 chips. It is quite recent model, few years old I think.
edit. here on this thread is photo. Link to my question and few posts below member Nisbeth shows it https://www.diyaudio.com/community/threads/accidental-short-icepower-200as2.398853/post-7348124
100as2 is with TPA3251
edit. here on this thread is photo. Link to my question and few posts below member Nisbeth shows it https://www.diyaudio.com/community/threads/accidental-short-icepower-200as2.398853/post-7348124
100as2 is with TPA3251
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Well that's completely news to me! I thought they made their own controllers. Thanks for that correction.
Yes the cooler they run the longer it takes them to warm up.... ICEpower was Putney's previous work and my Bel Canto S300i implementation specifically only goes to standby not off unless plug pulled. I can confirm a week's not enough; gossip was at least a month. My TPA3221 only takes several hours to sound good (so I leave it on too).
Power tubes warm up in a couple hours, but the small signal tubes take much longer so some preamps or hybrid amps go into standby instead of off to keep them warm. I once very carefully tested this on the Unison Research Unico hybrid amp and found it took six hours to fully stabilize, first two hours especially wild swings. Checked not the mosfet etc needed warm-up, by very quickly turn off, swap pre tubes using silicone glove, turn back on. Speakers Fostex F120A with big electrostatic supertweeter.
p.s. ICEpower used to only refer to iCDxxx Putney's work.
Power tubes warm up in a couple hours, but the small signal tubes take much longer so some preamps or hybrid amps go into standby instead of off to keep them warm. I once very carefully tested this on the Unison Research Unico hybrid amp and found it took six hours to fully stabilize, first two hours especially wild swings. Checked not the mosfet etc needed warm-up, by very quickly turn off, swap pre tubes using silicone glove, turn back on. Speakers Fostex F120A with big electrostatic supertweeter.
p.s. ICEpower used to only refer to iCDxxx Putney's work.
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I've been thrilled about the resurgence of large dome drivers, specifically all the new Bliesma Be and Alu diaphragm stuff.
Also like the advances in WG design, with 3D printing being so cheap to prototype it all. @augerpro Thank you for all the work done on the WGs.
Also like the advances in WG design, with 3D printing being so cheap to prototype it all. @augerpro Thank you for all the work done on the WGs.
This past decade I'm finally at long last beginning to see waveguided* tweeters gaining traction. Given the benefits of increased sensitivity and power handling, and the minimal cost increase of making essentially a different faceplate, I have long failed to understand why these have not become ubiquitous. Then again when I began as a loudspeaker engineer my older coworkers were really of a "cut and try" school and I feel there is a lot of conservatism and copyism amongst loudspeaker designers, with only some them really keeping up with the latest technical developments.
Purifi's refinements appear to be game changing, although I won't get excited until they release something with a sensitivity higher than abysmal.
And yeah I'll jump on the "good Class D at last!" bandwagon. Got an ATI 527NC, runs room temperature, cool to the touch.
*yeah what is a waveguide versus a horn, and it's really a sliding scale, but here I mean a regular tweeter into a fairly open and not huge horn structure. Like the Arendal, or Dayton Audio ND25FW-4, or the powered speakers my friend bought...argh the name escapes me, the waveguide is like the size of the woofer...ah Mads Buchardt.
Purifi's refinements appear to be game changing, although I won't get excited until they release something with a sensitivity higher than abysmal.
And yeah I'll jump on the "good Class D at last!" bandwagon. Got an ATI 527NC, runs room temperature, cool to the touch.
*yeah what is a waveguide versus a horn, and it's really a sliding scale, but here I mean a regular tweeter into a fairly open and not huge horn structure. Like the Arendal, or Dayton Audio ND25FW-4, or the powered speakers my friend bought...argh the name escapes me, the waveguide is like the size of the woofer...ah Mads Buchardt.
At the risk of offending our technorati, such shapes can be finger-moulded and listened to on-the-fly, from a roll of loose tape. I used 0.5mm-thickness gasket foam, backing paper unpeeled except at the innermost and outermost ends, to experiment with omni Lowther PM6A (after Citation 360).
https://www.diyaudio.com/community/threads/lowther.389573/post-7168314
(There ought to be a picture but I couldn't find it.)
https://www.diyaudio.com/community/threads/lowther.389573/post-7168314
(There ought to be a picture but I couldn't find it.)
Nothing new to me during the last ten years. (I haven't heard or used Purifi woofers or Bliesma mids)
My diy world was changed in around 2010-13 when I started designing my AINOgradient 4-way hybrid nude dipoles with minidsp and ICEpower amps, learned to use freeware sims and REW with a turntable for measurements. That process was possible largely by help from diyers at diyaudio.com - thank you all! And I'm still learning new stuff here every day! In this decade I've used Hypex FAxxx plateamps with integrated dsp.
https://www.diyaudio.com/community/threads/aino-gradient-a-collaborative-speaker-project.231353/
My diy world was changed in around 2010-13 when I started designing my AINOgradient 4-way hybrid nude dipoles with minidsp and ICEpower amps, learned to use freeware sims and REW with a turntable for measurements. That process was possible largely by help from diyers at diyaudio.com - thank you all! And I'm still learning new stuff here every day! In this decade I've used Hypex FAxxx plateamps with integrated dsp.
https://www.diyaudio.com/community/threads/aino-gradient-a-collaborative-speaker-project.231353/
Hi Barry, I've always been interested in TEF, since watching Heyser introduce TDS on SynAud Con vids..
Without trying to swerve too far off topic, does TEF do anything that Smaart can't do, or maybe does it better?
FIR is such a game changer.... I can't say enough about it as I've been circling back comparing it against the best IIR xover strategies I've seen.
I'm surprised more folks haven't jumped in with both feet, once they try it. My suspicion why they haven't, is that most of the reports seem to have tried to use FIR as a global correction on existing speakers, much like room correction. I think doing that rarely accomplishes more than becoming a fancy EQ, and for global corrections, one might as well stay IIR.
They need to try using FIR for linear-phase xovers, as a start.
Because the real value of FIR in my opinion, is when used for setting up active-multi-ways, with each driver channel getting its own FIR filter. Achieves flat mag and phase throughout the spectrum, along with spot-on time alignment. Crazy easy, crazy good.
It also has to be said that DSP has become very good thanks to cheap processing power being easy to integrate with other digital sources. Even an analog dinosaur like me can appreciate how easy it is to get the speakers in your untreated room to sound just like a great pair of open back headphones in a matter of a half hour. I also like that more people have been paying attention to vinyl playback, putting it in the path of conversation again. No, not really a game changer, but a step in the right direction.
A definite contribution to putting more excellent, high value drivers in reach to the diy building community is SB Acoustics. Their tweeters are some of the most advanced drivers at more reasonable prices. Where else can you get tweeters with copper shorting rings, vented non-conductive VC formers and chambered neo motors for under $40? Then there's the SB34NRXL75, which is possibly the best $300 12" woofer that will go shoulder to shoulder with a $700 Scanspeak 12" woofer?
A definite contribution to putting more excellent, high value drivers in reach to the diy building community is SB Acoustics. Their tweeters are some of the most advanced drivers at more reasonable prices. Where else can you get tweeters with copper shorting rings, vented non-conductive VC formers and chambered neo motors for under $40? Then there's the SB34NRXL75, which is possibly the best $300 12" woofer that will go shoulder to shoulder with a $700 Scanspeak 12" woofer?
Game changer has come. Hours earlier from Apple:
Four pro-grade mics spatial recording and AI localization/separation/re-mixing. AI spatial photo and video, VisionPro first-person viewer. AirPod as clinical-grade hearing aid.
A matter of time: AI binaural surround sound and immersive 360deg spatial video of live concerts by turning on both front & back cameras, self inserted on-stage live with sound.
Four pro-grade mics spatial recording and AI localization/separation/re-mixing. AI spatial photo and video, VisionPro first-person viewer. AirPod as clinical-grade hearing aid.
A matter of time: AI binaural surround sound and immersive 360deg spatial video of live concerts by turning on both front & back cameras, self inserted on-stage live with sound.
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VituixCAD. mabat. DSP for the masses (e.g. CamillaDSP). Class D amplification (with SOTA/near-SOTA performance). Maybe Purifi stuff.
Surround. I just discovered the “height” speakers in my Denon. They make a difference in movies. They are much better than adding more rear channels. I don’t have atmos so there is probably better surround processing by now. On the other hand, surround hasn’t improved much for the average guy and I’m thinking of going back to stereo or 3.2 rather than having 11 speakers everywhere. As a bass head it’s difficult for me to admit that most bass is actually noise centered on 50hz. Real bass is hard to find. Subwoofers are over-rated noise makers, real high fidelity woofers are way under-rated.
Digital amps are great, or they totally suck. I found that the sound can be improved with a 20% larger than required analog power supply, you know, a big transformer, big caps, good diodes. SMPS is getting better, better filters I guess. They make it a lot easier to have DSP loudspeakers. I see this stuff getting much better over the next few years.
Waveguides. They make the tweeter to midrange integration just, remarkable. I was heading down the ‘large, shallow, round, waveguide matched to the woofer diameter’ path years ago but 3d printing makes it accessible now. Much better than hand carving MDF! 😷
Arrays. They have significantly improved live sound. Shaded arrays are something I want to try.
Full range. Thanks to a little Chinese company, thousands of people got into building all kinds of full range loudspeakers from backwave horns to MLTL’s to towers of fun, and there are some amazing full rangers on the market now.
Room treatment. Finally foam is dead and people are using digital tools to make a decent listening environment.
Computer and TV audio. It’s not hifi but it’s getting much better due to digital processing.🤔
Cables. It’s good to see that this insane argument is still going on. Lamp cord rules! 🤣
Digital amps are great, or they totally suck. I found that the sound can be improved with a 20% larger than required analog power supply, you know, a big transformer, big caps, good diodes. SMPS is getting better, better filters I guess. They make it a lot easier to have DSP loudspeakers. I see this stuff getting much better over the next few years.
Waveguides. They make the tweeter to midrange integration just, remarkable. I was heading down the ‘large, shallow, round, waveguide matched to the woofer diameter’ path years ago but 3d printing makes it accessible now. Much better than hand carving MDF! 😷
Arrays. They have significantly improved live sound. Shaded arrays are something I want to try.
Full range. Thanks to a little Chinese company, thousands of people got into building all kinds of full range loudspeakers from backwave horns to MLTL’s to towers of fun, and there are some amazing full rangers on the market now.
Room treatment. Finally foam is dead and people are using digital tools to make a decent listening environment.
Computer and TV audio. It’s not hifi but it’s getting much better due to digital processing.🤔
Cables. It’s good to see that this insane argument is still going on. Lamp cord rules! 🤣
To my eyes on the hardware side there has been nothing of note over the last 10 years just a small evolution. On the social side things do appear to be changing more with a welcome (to me) shift away from audiophile/"subjectivist" fantasizing towards technical performance among home audio hobbyists. The former still seems to be dominant but the movement seems to be in the right direction (to me) which is good. Among the general non-hobbyist population though things seem to be shifting in the opposite direction with the adoption of a fair amount of audiophile/"subjectivist" hardware like records, valves, etc..
Purifi's woofer.
The CUE100 by lyngdorf is really nice and that's the first time I have a chance to listen to purifi's woofer.
Really something else.
The ultra low distortion in their datasheet manifest in the purest music content.
The CUE100 by lyngdorf is really nice and that's the first time I have a chance to listen to purifi's woofer.
Really something else.
The ultra low distortion in their datasheet manifest in the purest music content.
Depends on the model. Some products use the ICEedge chip by them so I think it's not the TI based chip.
No doubt that the 200AS2 is the one based on TI.
Hype/denial and the placebo effect are sufficient for a short while, and then you must rely on attitude and eventually double down with piety. Real improvements may be a field of dreams to some, sufficient for the believers alone.
I will never stop marveling at some of the nonsense, yet somewhere, every so often, a reality takes hold and the inventor usually dies a poor man with a good heart.
God, it felt good to type that. Still great audio still fascinates me to this day.
I will never stop marveling at some of the nonsense, yet somewhere, every so often, a reality takes hold and the inventor usually dies a poor man with a good heart.
God, it felt good to type that. Still great audio still fascinates me to this day.
DSP speaker management and class D amps have been the biggest game changers for me. I never thought I'd be the guy running 6 amps to power a pair of 3-way horns, but here I am. I'm even more amazed by how affordable it's gotten.