KeithL
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Posts: 10,274
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Post by KeithL on Dec 23, 2022 11:28:54 GMT -5
Back at Fairchild they actually did shut down the wave over weekends... The big thing was to NOT turn on the pump until it reached operating temperature... and all the solder was liquid... which took a few hours. (I don't even want to think about how powerful the heaters were... that little tank held a LOT of pounds of solder.) ........................................... Pump?? Solder? Can't EVER let it go cold or you'll probably never get it going again....... |
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KeithL
Administrator
Posts: 10,274
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Post by KeithL on Dec 23, 2022 11:42:49 GMT -5
As I said the audible difference is pretty subtle... To the point where it won't be audible at all except on certain few specific sounds in specific recordings... Try listening to the 24/192 version of The Eagles - Hotel California. Listen carefully to the sound of the plucked guitar strings. Try and imagine that you can hear things like whether the strings sound "metallic" or "like something softer like nylon"... And switch between Filter 1 and Filter 2. Depending on what speakers or headphones you're using you'll hear a tiny difference... (Maybe the strings sound "a little harder" on Filter 1... and "a little more natural" on Filter 2...) Or you could try a recording you're very familiar with that includes some wire-brush cymbals... They sound "a little bit more like actual wires hitting a piece of metal" on some filters than others. Or whether they sound "just a tiny bit more shimmery"... THAT is the level of differences that we're talking about here... To be honest I pretty much stopped obsessing over these sort of differences... (right when I noticed that I was keeping copies of two or three tracks handy JUST because they allowed me to hear differences like this...) Note that some DACs, like Sabre DACs, if they're implemented a certain way, have really extreme differences between filters. And, on some DACs, one option will be a slow-rolloff filter that cuts in so low that you really hear the drooping high end... Those types of filters tend to make guitar strings sound very clean and mellow... but at the expense of other many things... and, of course, not being accurate. (But I consider that to be the exception... and a bit of that "hope people will assume that different is better" attitude.) ...The most accurate choice is going to be "shortest possible ringing arranged symmetrically before and after"... But many people seem to agree that, at least with some instruments, a filter with "no pre-ringing and more post-ringing" "sounds more natural". Our Ego+ DACs offer both of these options... and the ability to switch back and forth relatively easily. And, on at least a few recordings, I can hear a slight difference between them (but only a few). Although, to be fair, I cannot claim to know which is actually better. And that's an excellent experiment that anyone with one of our Ego DACs should try... see which filter choice YOU like better... ... Your ears are better than mine, KeithL - I swapped back and forth on my Big Ego+ but couldn't really hear a difference. The few times I thought I did, I did the switch again and decided that I really didn't. |
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Post by leonski on Dec 23, 2022 15:34:31 GMT -5
As I said the audible difference is pretty subtle... To the point where it won't be audible at all except on certain few specific sounds in specific recordings... Try listening to the 24/192 version of The Eagles - Hotel California. Listen carefully to the sound of the plucked guitar strings. Try and imagine that you can hear things like whether the strings sound "metallic" or "like something softer like nylon"... And switch between Filter 1 and Filter 2. Depending on what speakers or headphones you're using you'll hear a tiny difference... (Maybe the strings sound "a little harder" on Filter 1... and "a little more natural" on Filter 2...) Or you could try a recording you're very familiar with that includes some wire-brush cymbals... They sound "a little bit more like actual wires hitting a piece of metal" on some filters than others. Or whether they sound "just a tiny bit more shimmery"... THAT is the level of differences that we're talking about here... To be honest I pretty much stopped obsessing over these sort of differences... (right when I noticed that I was keeping copies of two or three tracks handy JUST because they allowed me to hear differences like this...) Note that some DACs, like Sabre DACs, if they're implemented a certain way, have really extreme differences between filters. And, on some DACs, one option will be a slow-rolloff filter that cuts in so low that you really hear the drooping high end... Those types of filters tend to make guitar strings sound very clean and mellow... but at the expense of other many things... and, of course, not being accurate. (But I consider that to be the exception... and a bit of that "hope people will assume that different is better" attitude.) Your ears are better than mine, KeithL - I swapped back and forth on my Big Ego+ but couldn't really hear a difference. The few times I thought I did, I did the switch again and decided that I really didn't. Well, Keith? We are FINALLY at the 100% level. I stopped obsessing a decade or more ago. I was just gobsmacked when I heard my first CD played thru a decent (not crazy good) system. My RSL3600 speakers were credible and excellent copies of JBL4311 to the point of being used in a few SoCal recording studios. But when I bought my first (used) Maggies? That was IT..... Today? If I had 'my wish'? It would be to compare my original Magnevox FD-1000 with any current offering......as long as we were restricted to 16/44 material.... |
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Post by Boomzilla on Dec 24, 2022 16:38:36 GMT -5
My "must have" list for any new DAC:
1. Asynchronous USB input (don't care about others)
2. Both XLR and RCA analog outputs
3. Volume control with remote
4. One set of RCA analog inputs
My "would prefer to have" list for any new DAC:
1. Silver rather than black paint
My "would prefer to avoid" list for any new DAC:
1. Wireless ability
2. Bluetooth ability
3. High price
YMMV
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Post by audiobill on Dec 24, 2022 17:23:08 GMT -5
Add:
Strong, non switched power supplies, independent for each channel and separate for digital and analog stages
High quality film capacitors
Discrete analog stage, no opamps allowed
Stepped attenuators
Robust casework and controls
Sabre 9038 pro dac
AES/EBU
Switchable Multibit/D/S conversion
Lifetime transferrable warranty
@keithl
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Post by Boomzilla on Dec 30, 2022 20:15:58 GMT -5
Comments to date on the iFi Zen Streamer:
Out of the box, the unit had a "quick start guide," a card with the features of the device (semi) identified.
A review of the quick start guide seemed to indicate that it was for enablement of the wireless features of the streamer. I don't want to use my streamer with wireless, so instead I connected my Ethernet cable, my USB cable to the DAC, and the power supply to the Zen. Power on - looks good - the LED on the front indicates "high speed connection."
So I'm sitting back ready to listen and... Nothing. Roon says my selection is playing - Roon sees the iFi Zen streamer - It is selected as the active audio zone - The DAC is set to USB input & variable volume - The power amps are on - No sound.
The first step of troubleshooting (since this rig was working before I substituted the Zen for my previous Apple TV) was trying to determine whether my USB cable to the DAC is plugged into the right USB port on the Zen. The Zen has two. One is an input only for a data HDD (won't be using this one at all). Second is an output only for the DAC. But although the information from iFi calls them "Port A" and "Port B," the features card fails to say which (top or bottom) is which. Further, the ports aren't labeled on the device either.
Long story short - I try switching ports on the Zen. Result: Still no audio.
Second step of troubleshooting (since this device will be working ONLY with Roon), I'd set the mode switch on the Zen to "Roon only." When I turned the Zen on, the front panel LED lit up to Indicate "high speed connection." Thought I was good to go. No dice. No music.
Third step of troubleshooting (after viewing a YouTube video for setup as Ethernet only), I turned the mode switch back to "All In One" (AIO) turned the Zen off, and then turned it on again. No music.
Fourth step of troubleshooting - I entered "http://ifi.local into my MacBook Pro's browser (Safari). I'm supposed to get a Zen setup screen. No dice - the page won't load. Period. I double checked - the MacBook is on the same Ethernet network as the Zen.
Fifth step of troubleshooting - I scraped off the "stuck on for life" cover off of the Zen's reset button & pushed reset. Zen came up - "high speed" light lit - tried iFi.local in my browser again. Nothing.
Stopped & drank an adult beverage. Left the Zen alone for long enough to calm down. Wrote this post to blow off steam.
Opened a new browser window - tried again to access the setup page - Nothing again.
THOROUGHLY fed up with iFi. If I get it working, I'll let ya know.
Boomzilla
Postscriptum -
There's a wealth of information available on the iFi Zen user forums that iFi didn't see fit to include on their Streamer user manual. Among those factoids:
The bottom of the two USB ports on the Zen is the output port for a DAC. The topmost port is for external storage only. The manual doesn't say this.
If the coaxial port is "live" as an output (which it is by default), then the USB port is disabled! This seems insane, but that's how it is. The manual doesn't say this.
To enable the USB port, one has to open the HTML setup program on a computer that is directly connected(wired via Ethernet) to the Zen. The manual doesn't say this.
To get to the HTML setup program, the mode switch on the Zen must be set to "AIO" ("All-In-One"). Not to "Roon Only" (even if you plan to use the device as a Roon-only device). Changes to the setup are HTML only / AIO mode only. I couldn't even open the configuration URL with the Zen in anything other than AIO mode. The manual doesn't say this.
To enable high resolution modes such as 24/96, the HTML setup page must be used. The manual doesn't say this.
After every change of the mode switch on the Zen, the unit must be shut down and restarted. The manual doesn't say this.
Once properly set up and working, I tried the coaxial RCA SP/DIF interface to my Emotiva Stealth DC-1 DAC. It sounded no differently than my Apple TV3 (that has optical audio output only and cost $10). I'll listen to the USB interface today.
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Post by dougport on Dec 31, 2022 1:22:31 GMT -5
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Post by Boomzilla on Jan 2, 2023 11:46:14 GMT -5
A watershed in my audio journey is here. I'm selling my beloved and unique Heathkit vacuum tube mono power amplifiers. I take this step with trepidation. I've never owned (or heard) any amplifiers as dynamic and exciting as these, but I need to let them go anyway. So first, let me list what makes these amps so exceptional:
They came to me from a yard sale as monophonic integrated amplifiers. As such, they were virtually useless in any modern stereo system. The preamplifier sections of these amps had but one line-level input, their other input being for a (mono) ceramic phono cartridge.
So I opted instead to strip all of the preamplifier circuitry from the amps leaving only the circuitry downstream of the volume pots. From that point on, I rebuilt the circuit using polystyrene capacitors and metal-film resistors. All parts were "overbuilt." Where the circuit had previously used a quarter-watt carbon resistor, I installed a half-watt metal film of the same value. Where a capacitor had been rated at 200 volts, I installed a 400 volt or higher model of the same value.
Heathkit originally claimed that the ampliifiers had 12 watts capacity, but that was before standardized measurements came into common use. By today's measurement standards, the amps would probably be rated for about five or six watts each. This means that the little amplifiers can work fine with high sensitivity speakers. I used them with Tekton Pendragons, Tekton Double Impacts, Klipsch Cornwalls, Emotiva T-2s, and Klipsch RP-600m monitors with stunning impact.
What makes the Heathkits sound so stunning? Believe it or not, it is their distortion that sets them apart. "Normal" listening (particularly with high-sensitivity speakers like the ones I've listed above) is done a less than one watt. When an audio peak comes along, the Heathkits (whose distortion rises linearly with output) increases its distortion. Remember that even at one watt, the amps are playing at 20% of their total output levels... But the human ear doesn't hear this second-order distortion as "distortion." Instead, the ear interprets the distortion as "loudness," thus giving an apparent expansion in dynamic range to the music.
This effect causes the amplifiers to sound extremely dynamic and "alive." I've never owned (or heard) another amplifier that makes music so much fun to listen to.
Along with the amps' stunning musical presentation, however, comes some unavoidable minor issues. First, since you'd have to use these amps with highly sensitive speakers, the noise floor of the amps can become an issue. The amps have a touch of hiss and hum. But if you're more than two or three feet from the speakers, it isn't audible. But to get the noise down to that level, you have to pay attention to everything. Your audio interconnect cables need to be well shielded and dressed away from power cords; the polarity of the AC plug of each amp needs to match the polarity of the preamplifier and of each other; your speaker cables need to be shielded and dressed away from power cords.
Also, the amplifiers, although of the same Heathkit model number, apparently came off the production line with slightly different parts. This was not unusual for Heathkit since they bought a lot of military surplus parts post WW-2 and sold them for decades after. The secondary taps of one of the two power transformers are a few volts hotter than the same taps from the other transformer. So one of the two amps has slightly (but only slightly) more gain than the other. If you have a preamplifier with a balance control, you can exactly balance the two channels. If not, the difference isn't noticeable in most rooms. The frequency response is also not quite as flat as would be true of a solid-state amp. But the frequency non-linearities are an artifact of the apparent increase in dynamic range. You don't get one without the other.
And finally, as is true for all tube amplifiers, the little amps generate significantly more heat than do solid state amplifiers of any output wattage. You'd therefore need to provide the amps with more ventilation than a solid-state amp would require.
The schematic for the original amp is downloadable from the internet. The modified schematic for the changes I've made comes with the amps. If one wanted to take the time, I'm positive that the amps could be further modified to significantly reduce noise and possibly to increase the output wattage.
Why am I selling the best-sounding amps I've ever owned? I've purchased a new set of speakers, the GoldenEar Triton Three+ models, that have a rated sensitivity of 90dB / 1W / 1m. This rating is optimistic. I'd guess the speakers to be 87-88 decibels instead. This is still pretty good, but it's just low enough that the Heathkits struggle to drive them. We're also about to move out of state, and the less stuff I have to pack and move, the easier and cheaper the move will be.
So that's it. Adios to the giant-killer Heathkits. I hope they find a loving home. They deserve it.
Boomzilla
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Post by cwmcobra on Jan 2, 2023 14:51:39 GMT -5
I have a soft spot for Heathkit products. Living in Michigan, I was able to make a few trips to the factory showroom. That started my journey into kit building. My first, while in college, was an AR-15 stereo integrated amplifier sourced with a small Crown tuner and a Dual turntable. It drove a pair of 12" two way speakers that I bought from Allied Radio and built into to mahogany cabinets. That system was sold to fund an engagement ring for my now wife of 51 years. A good investment, for sure. After college I made another trip to the showroom again with plans to buy an AR-1500 receiver kit and a pair of Advent AR-3 kits. But the showroom changed my approach to speakers and I opted for a pair of JBL 14" two-ways instead of the Advents. And I've been a high sensitivity speaker lover ever since! See my signature....
I also build a couple of Heathkit TVs, one for my parents and one for me. That was the end of my Heath builds. On the audio front I moved from the Heathkit AR-1500 to a used Dynaco Stereo 400 amp sourced with a Kenwood tuner connected to a Dyanco PAT-3? preamp that I built. Had that rig until I got into home theater many years later. And the beat goes on....
I agree Glenn, hoping your Heathkit amps find a good new home, speaking nostalgically!
Chuck
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Post by Boomzilla on Jan 4, 2023 8:16:22 GMT -5
Further adventures with the iFi Zen Streamer: I've enabled 24/96 at the Roon source. I've enabled 24/96 on the iFi Zen Streamer. My DAC is 24/96 capable. BUT - Unless your source is 24/96, you get what showed up in your source file (most often 16/44). USB is selected as the output source on the Zen. Additionally, with the setup above, you will get thunderous silence if you set your iFi Zen Streamer to "Roon Only" mode. Why, I don't know. You HAVE to use AIO (All-In-One) mode to get music. So how does USB sound with the above settings? Pretty spiffy! Music has a transparency and level of detail that are fun to listen to. More engaging than what I heard with TOSLINK optical and RCA SP/DIF I think. I've also made a few room changes to enhance listening: 1. I've pulled my speakers out into the room by about 2.5 feet from the wall behind them. This does reduce the bass compared to having the speakers closer to the wall, but since the woofers on the GoldenEar are self-powered, I can just dial up the bass a bit and restore as much bass as I want. 2. I"ve changed from listening on my couch to using a folding chair placed not only in front of the couch but also in front of the coffee table in front of the couch. This does several things - First, it reduces slap echo from the wall behind the couch. In the past, this echo muddled the midrange and even with absorbers placed behind the couch, the muddle remained. Second it reduces slap echo from the coffee table itself. In the past, I had to move the coffee table if I wanted to do critical listening and even then, I had to contend with slap echo from the wall behind the couch. Third, the new listener placement puts the listener's ears about six to eight feet from the front of the speakers. This provides more direct sound and less room sound. 3. I've installed a speaker switch that lets me use either my Emotiva PA-1 power mono block amplifiers or my Black Ice Audio F22 tube integrated amplifier. For music, I prefer the tube amp. For movies or loud rock, I prefer the solid-state ones. Make of this what you choose. 4. I've adjusted the fore-aft tilt of the speakers to point their ribbon tweeters exactly at my ears. You wouldn't think that this would make much difference, but it does. The result is that I'm getting better sound out of the same room without having spent a penny. Is it as jaw-dropping as my audio amigo, Russell's rig? No, it isn't but it's a lot closer. The next time I'm able to get garbulky, aka "the speaker dancer" over here, we'll try moving the speakers around to see if there's a better position for them. Cheers - Boomzilla |
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Post by leonski on Jan 4, 2023 15:30:15 GMT -5
When the Tube Amp is NOT SELECTED....are the outputs loaded or 'open'? Isn't tube gear always supposed to have an output load...?
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Post by Boomzilla on Jan 4, 2023 16:50:40 GMT -5
When the Tube Amp is NOT SELECTED....are the outputs loaded or 'open'? Isn't tube gear always supposed to have an output load...? You're absolutely right, leonski. Tube amplifiers do NOT like playing into infinite resistance. I'm therefore careful to turn off the tube amplifier power switch prior to switching the speaker load to the solid state amps and equally careful to select the tube amplifier's connections to the speakers prior to turning on the tube amp's power switch. I think I could probably do away with this requirement by hooking up a 25 or 50 ohm resistor between the ground and hot speaker taps of the tube amp. It wouldn't be good to leave it playing into that output resistance for hours on end, but for short-term protection it should work OK. |
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Post by leonski on Jan 4, 2023 17:20:03 GMT -5
you could fix up a circuit with RELAY switching so that when the tube amp is Unselected, it flips the outputs to maybe a 10ohm......10 watt wirewound.....  I don't know about 'break before make'......or 'make before break'....either of which may cause problems...... |
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Post by Boomzilla on Jan 4, 2023 19:36:08 GMT -5
I don't plan to switch back and forth very often - Tube amp for music, solid-state ones for movies. I think I'll leave it as is for now.
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Post by Boomzilla on Jan 6, 2023 9:41:39 GMT -5
Further notes on the iFi Zen Streamer:
The iFi Zen Streamer is not a simple audio product because of its capabilities. With versatility comes the necessity of user configuration.
Yet a consumer should not have to avail themselves of a half-dozen YouTube videos to get their product to work (nor yet have to spend days in a user forum relying on the generous advice of others).
The iFi Zen Streamer is a singularly difficult product to configure. Those who claim otherwise may have been fortunate with their setups. But not everybody is so fortunate. The volume of internet traffic regarding setup of this iFi product confirms my statements.
The device could have been engineered for a simpler user experience, but it is what it is. That being the case, it is the unequivocal responsibility of the manufacturer to provide a comprehensive user manual, either on paper or via the internet. This, iFi has failed to do.
That's a shame, because once configured, the product works and sounds good. But for $400, I expected better in terms of usability and ease of setup.
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Post by audiobill on Jan 6, 2023 20:21:09 GMT -5
Thanks, Boom.
Think I’ll skip the streamer thing and continue being happy with my mac mini usb connection to dac via usb!
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Post by leonski on Jan 7, 2023 2:06:35 GMT -5
Further notes on the iFi Zen Streamer: The iFi Zen Streamer is not a simple audio product because of its capabilities. With versatility comes the necessity of user configuration. Yet a consumer should not have to avail themselves of a half-dozen YouTube videos to get their product to work (nor yet have to spend days in a user forum relying on the generous advice of others). The iFi Zen Streamer is a singularly difficult product to configure. Those who claim otherwise may have been fortunate with their setups. But not everybody is so fortunate. The volume of internet traffic regarding setup of this iFi product confirms my statements. The device could have been engineered for a simpler user experience, but it is what it is. That being the case, it is the unequivocal responsibility of the manufacturer to provide a comprehensive user manual, either on paper or via the internet. This, iFi has failed to do. That's a shame, because once configured, the product works and sounds good. But for $400, I expected better in terms of usability and ease of setup. SOMEBODY needs to write a concise set of directions........ I wrote complex procedures to teach to, and this is no different. Several possible formats occur from .....You want to XXX than do THIS...... A series of trouble shooting steps would also be nice. And design instructions ONE POINT at at time.......KISS is the principle. Sure, the guy that built / designed / tested is a pro. So what? If BOOM had trouble? Imagine someone with lesss persistance and background dealing with technical stuff. My OPINION? It should be possible to make a video disc with a series of setup videos. |
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Post by Boomzilla on Jan 15, 2023 21:14:16 GMT -5
It never seems to fail... While cleaning the garage in 2022, I found that I had no less than six ⅜" drive socket sets. Knowing that I'd never need that many, I sold or gave away four of the six. That left me with two full sets (more than I should need). So tonight I'm doing a job that requires a SAE deep-socket and of course I can't find EITHER of the two sets I kept! I've found two ¼" drive sets, neither of which has a socket large enough for the nut that needs tightening. Having wasted a full hour now looking for the tools I know I have, I've given up and will go buy another set tomorrow morning.
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Post by cwmcobra on Jan 15, 2023 22:21:40 GMT -5
Happens to the best of us. Unfortunately, more frequently as we get older...been there, done that way to often!!  |
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Post by novisnick on Jan 16, 2023 0:22:07 GMT -5
I don't plan to switch back and forth very often - Tube amp for music, solid-state ones for movies. I think I'll leave it as is for now. I too have a switch box for selecting preamps and amps as well as speakers. Best solution I’ve found was to make a habit of making my selections prior to anything being powered up. After I shut down my system I always turn all my selectors to HT mode. Having good habits does away with putting something in the way of the signal. Always, Enjoy the music/ sound. Have fun Boomzilla |
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