Help on Japanese translation of a Jigsaw user manual
- By juanito
- Equipment & Tools
- 10 Replies
Hello,
I'm trying to find out if this vintage Ryobi jigsaw can attach T blades. In these instruccrions (linked below) I can see that there are pictured in page 11. I know that the original blades aren't T or U types, they are straight and with a hole (blades 1, 2 and 3 in page 11). Jut wondering what does it say for the rest of blades which apparently are T type. I guess it's japanesse because the web site is from Japan. Also these instructions are images so no way for me to copy paste text and google translate.
Thanks in advance for your time and help: MUCH apreciated!!:
:
https://www.kyocera-industrialtools.co.jp/products/files/doc/7304528308c705eb60c15be84640eae2.pdf
I'm trying to find out if this vintage Ryobi jigsaw can attach T blades. In these instruccrions (linked below) I can see that there are pictured in page 11. I know that the original blades aren't T or U types, they are straight and with a hole (blades 1, 2 and 3 in page 11). Jut wondering what does it say for the rest of blades which apparently are T type. I guess it's japanesse because the web site is from Japan. Also these instructions are images so no way for me to copy paste text and google translate.
Thanks in advance for your time and help: MUCH apreciated!!:
:https://www.kyocera-industrialtools.co.jp/products/files/doc/7304528308c705eb60c15be84640eae2.pdf
Build Thread: DIY Tube Preamplifier (KSL-M77 Clone-Based)
- By jwpettit
- Analog Line Level
- 3 Replies
Hello! My name is Jeff and I'm new here on DIY Audio, so just wanted to start this thread off with a quick intro post. I'm setting out to build my own Hi-Fi setup with all DIY components and the first piece I'll be tackling will be my preamplifier.
I want to document my process through a thread as 1: I will have many many questions which I know I'll be able to get answered here, and 2: I find it super helpful to review detailed guides complete with photos when learning about these builds, so only fair I give some back. Please note that I am a complete novice to electrical engineering/circuit design, etc. so many of my questions will be "dumb questions". I have a basic understanding of what a resistor and a capacitor do, and know how to solder, but that's about it. Please be patient with me and if already resources exist, kindly point me in the right direction.
I am by trade an industrial designer, so designing consumer products is something that I have quite a bit of experience with, and building this preamp is going to be fun for me. It will be a custom-designed chassis that I will be producing via 3D printing. For the internals, I'm going to be using one of the Chinese KSL-M77 circuit-clone boards as a basis. I know the China clone products can be a bit controversial sometimes so I'd like to make it clear, I am not setting out to build a knockoff of or homage to the M77, rather using using one of these boards as a basis for my custom preamp. My result will be a very very different thing to the original, and I'm making no claims that it will be the same or some match to a genuine M77.
Why did I choose this board? Good question. I was originally considering to use one of the clones to the Marantz M7/Shigeru Wada circuit design which exist (I know those are two different things but they often get used interchangeably). While researching these I discovered the M77, and after reviewing it seemed like a superior design. As mentioned above, I am not very well-versed in electrical engineering, so I'm not able to look at the circuit diagram and understand too much about how it works. However, I do understand a few superiorities this design has:
I ordered a raw board from Aliexpress as I intend to solder in each of the electrical components myself. I feel like this will be a good thing for me to work on in the evenings over watching TV, and wanted to source my own high-quality (audio-grade where possible), name-brand components. Once I receive the board, the first thing I'll do will be to compile a BOM for review.
The other main reason that I wanted to get the un-propagated board is that I intend to assemble it a little differently than the standard configuration. Taking inspiration from some of the M7/Shigeru Wada clone boards I've seen online (see photo), I plan to mount many of the components (particularly large ones) to the underside of the board rather than the top. The goal is to mount the board high in the chassis, and have the tubes exposed outside of the enclosure like many high-end audio components do. I understand that mounting heat-sensitive components like capacitors underneath the board will be thermally sub-optimal, however I plan to design in heat-sinks surrounding them in order to assist with this, and ensure there is plenty of airflow in my design for the chassis.
So excited to get started on this, and hopeful for good advice from those who've built this board before. PCBs should arrive in a couple weeks. Stay tuned for updates!
Thanks!
I want to document my process through a thread as 1: I will have many many questions which I know I'll be able to get answered here, and 2: I find it super helpful to review detailed guides complete with photos when learning about these builds, so only fair I give some back. Please note that I am a complete novice to electrical engineering/circuit design, etc. so many of my questions will be "dumb questions". I have a basic understanding of what a resistor and a capacitor do, and know how to solder, but that's about it. Please be patient with me and if already resources exist, kindly point me in the right direction.
I am by trade an industrial designer, so designing consumer products is something that I have quite a bit of experience with, and building this preamp is going to be fun for me. It will be a custom-designed chassis that I will be producing via 3D printing. For the internals, I'm going to be using one of the Chinese KSL-M77 circuit-clone boards as a basis. I know the China clone products can be a bit controversial sometimes so I'd like to make it clear, I am not setting out to build a knockoff of or homage to the M77, rather using using one of these boards as a basis for my custom preamp. My result will be a very very different thing to the original, and I'm making no claims that it will be the same or some match to a genuine M77.
Why did I choose this board? Good question. I was originally considering to use one of the clones to the Marantz M7/Shigeru Wada circuit design which exist (I know those are two different things but they often get used interchangeably). While researching these I discovered the M77, and after reviewing it seemed like a superior design. As mentioned above, I am not very well-versed in electrical engineering, so I'm not able to look at the circuit diagram and understand too much about how it works. However, I do understand a few superiorities this design has:
- There are more tubes. Maybe they're excessive, and they'll definitely cost more $$$. But more = better right? (Maybe not but go with it anyway.)
- The volume potentiometer is integrated into the circuit itself. When reading about where to integrate the volume pot on a design which doesn't have one there seems to be some healthy debate about whether its best to attenuate on the input or output, with consensus stating optimally its somewhere in the middle. This appears to do that.
- Lines in and out don't share ground between L and R channels.
- Lastly, there's a built-in phono stage. So even though this build costs more, its one less component that I need to buy or build.
I ordered a raw board from Aliexpress as I intend to solder in each of the electrical components myself. I feel like this will be a good thing for me to work on in the evenings over watching TV, and wanted to source my own high-quality (audio-grade where possible), name-brand components. Once I receive the board, the first thing I'll do will be to compile a BOM for review.
The other main reason that I wanted to get the un-propagated board is that I intend to assemble it a little differently than the standard configuration. Taking inspiration from some of the M7/Shigeru Wada clone boards I've seen online (see photo), I plan to mount many of the components (particularly large ones) to the underside of the board rather than the top. The goal is to mount the board high in the chassis, and have the tubes exposed outside of the enclosure like many high-end audio components do. I understand that mounting heat-sensitive components like capacitors underneath the board will be thermally sub-optimal, however I plan to design in heat-sinks surrounding them in order to assist with this, and ensure there is plenty of airflow in my design for the chassis.
So excited to get started on this, and hopeful for good advice from those who've built this board before. PCBs should arrive in a couple weeks. Stay tuned for updates!
Thanks!
Attachments
Cabinet Veneer Techniques
- By Kyngfish
- Full Range
- 13 Replies
I’ve built 3 different cabinets at this point, and my woodworking and equipment keeps getting better every year. My first was an MLTL a long time ago that was garbage, then I built a Dallas II that was - fine, and then I built a Pensil for my 10p and they turned out pretty good. Since then I’ve built a few pieces of solid wood furniture I managed to sell during COVID and I’m ready to turn the skills I’ve learned into a new set of cabinets. Considering the FHXL.
This time I want to lay a nice veneer down on the Baltic birch and was hoping for some pointers.
Generally I like to round over my corners to make the design look a little more finished and to take a little “weight” out of the design - but I’ve only ever done solid wood construction, and I’m wondering what the best way to deal with those rounded corners is if I wanted to add veneers.
I was considering painting the cabinets black, and leaving the black detail as part of the round over corners, while only veneering the straight parts of the panel. This would frame the wood veneer a bit.
Can anyone show me some designs they’ve done and what they prefer? I worry that veneering over the round over won’t look right, as a “real” round - over will reveal the grain in a different way than looking at it head on. I also worry that the black “framing” will look too rustic or unfinished.
I know you all on here have probably done a bunch of great stuff, so hoping someone can show me what’s up.
Pic of the last consoles i did to hopefully prove I’m not all thumbs, and to show you more or less how I design the stuff in my house. 🙂
This time I want to lay a nice veneer down on the Baltic birch and was hoping for some pointers.
Generally I like to round over my corners to make the design look a little more finished and to take a little “weight” out of the design - but I’ve only ever done solid wood construction, and I’m wondering what the best way to deal with those rounded corners is if I wanted to add veneers.
I was considering painting the cabinets black, and leaving the black detail as part of the round over corners, while only veneering the straight parts of the panel. This would frame the wood veneer a bit.
Can anyone show me some designs they’ve done and what they prefer? I worry that veneering over the round over won’t look right, as a “real” round - over will reveal the grain in a different way than looking at it head on. I also worry that the black “framing” will look too rustic or unfinished.
I know you all on here have probably done a bunch of great stuff, so hoping someone can show me what’s up.
Pic of the last consoles i did to hopefully prove I’m not all thumbs, and to show you more or less how I design the stuff in my house. 🙂
Steinberg UR44C: Review
- By peufeu
- Digital Line Level
- 10 Replies
I bought this USB3 soundcard to make measurements on various things, so... it's review time.
Unboxing
It looks nice and heavy, all metal case, quite flattering and robust. If you drop it, make sure it lands on the back, as they designed in a nice flange to protect the connectors. There is the same flange on the front, but it is too short to protect the knobs.
It is easy to open, just 4 screws.
Software installation and overall user experience
As tradition requires, the firmware updater crashed mid-update, bricking the device. Fortunately, the embedded guys at Steinberg are smart, so the embedded bootloader was still running and eager to load working code into its flash.
However, the PC software was written by idiots. The updater proudly displayed that the device had the latest firmware installed, and did not need to be updated. Noticeably, it lacked an "UPDATE IT ANYWAY FFS" button. Who needs to verify the checksum to make sure it is properly flashed? Just check the version byte and tada! done.
Customer support does not exist.
So I loaded the firmware upgrade app in the debugger, stepped through the asm code, found the place where it got the version number from the device, decremented the last digit in the memory dump, and hit "RUN". The idiot software was very happy to inform me that the device had the firmware version number I had just typed, and that it would update it.
It was a bit more complicated than this, but I'll spare you the details. I don't know why a firmware updater needs 15 threads and 2 state machines in 2 different threads to process sending and receiving USB messages, though. Mystery.
This time, it worked, and it unbricked itself.
The ASIO drivers are solid, no crash or bluescreen, which is worthy of notice.
Yamaha is very proud of their reverb (it does sound nice), and the PC software is written by idiots, so you have to look into google to find out how to disable the reverb, then find out for yourself. It has to be disabled in both mix busses, and the DAW has to be set to "solo", otherwise the inputs feed through into the outputs, which is what it's supposed to do if you're recording live and want to hear yourself playing.
Anyway.
USB port
It has a USB 3.1 type C port so it can power itself from a PC with a USB-C port. It also has a wall wart if you don't have a USB-C port. That's nice. It doesn't use the USB3 throughput, so it works fine on USB2, with the wall wart.
It doesn't work on Linux.
4 line outputs on 6.35 jacks
They are balanced, in the sense that they output a positive and negative signal:
Full scale digital output, 6.32 Vpp on the tip, 8.64 Vpp on the sleeve, so you get a bit extra signal for free.
When either the tip or the sleeve is shorted, it does not distort, as some balanced drivers sometimes do. Instead it doubles the output on the other polarity, which is nice, and of course it clips hard.
So you have to halve the level in software, for example to 0.45 full scale instead of 1. There is no analog gain control. Anyway, the outputs work.
2 "main outputs" line outputs on 6.35 jacks, with volume pot, same signal goes to 2 headphone jacks, each with volume control.
These output the mix bus, so the PC can't use them as outputs. Even though it can, because it does, and the interface declares itself as 6 channel, but if you try to output a signal on them, it doesn't work. 4 outputs are fine, I don't need 6, so this is a problem for another day.
Unboxing
It looks nice and heavy, all metal case, quite flattering and robust. If you drop it, make sure it lands on the back, as they designed in a nice flange to protect the connectors. There is the same flange on the front, but it is too short to protect the knobs.
It is easy to open, just 4 screws.
Software installation and overall user experience
As tradition requires, the firmware updater crashed mid-update, bricking the device. Fortunately, the embedded guys at Steinberg are smart, so the embedded bootloader was still running and eager to load working code into its flash.
However, the PC software was written by idiots. The updater proudly displayed that the device had the latest firmware installed, and did not need to be updated. Noticeably, it lacked an "UPDATE IT ANYWAY FFS" button. Who needs to verify the checksum to make sure it is properly flashed? Just check the version byte and tada! done.
Customer support does not exist.
So I loaded the firmware upgrade app in the debugger, stepped through the asm code, found the place where it got the version number from the device, decremented the last digit in the memory dump, and hit "RUN". The idiot software was very happy to inform me that the device had the firmware version number I had just typed, and that it would update it.
It was a bit more complicated than this, but I'll spare you the details. I don't know why a firmware updater needs 15 threads and 2 state machines in 2 different threads to process sending and receiving USB messages, though. Mystery.
This time, it worked, and it unbricked itself.
The ASIO drivers are solid, no crash or bluescreen, which is worthy of notice.
Yamaha is very proud of their reverb (it does sound nice), and the PC software is written by idiots, so you have to look into google to find out how to disable the reverb, then find out for yourself. It has to be disabled in both mix busses, and the DAW has to be set to "solo", otherwise the inputs feed through into the outputs, which is what it's supposed to do if you're recording live and want to hear yourself playing.
Anyway.
USB port
It has a USB 3.1 type C port so it can power itself from a PC with a USB-C port. It also has a wall wart if you don't have a USB-C port. That's nice. It doesn't use the USB3 throughput, so it works fine on USB2, with the wall wart.
It doesn't work on Linux.
4 line outputs on 6.35 jacks
They are balanced, in the sense that they output a positive and negative signal:
Full scale digital output, 6.32 Vpp on the tip, 8.64 Vpp on the sleeve, so you get a bit extra signal for free.
When either the tip or the sleeve is shorted, it does not distort, as some balanced drivers sometimes do. Instead it doubles the output on the other polarity, which is nice, and of course it clips hard.
So you have to halve the level in software, for example to 0.45 full scale instead of 1. There is no analog gain control. Anyway, the outputs work.
2 "main outputs" line outputs on 6.35 jacks, with volume pot, same signal goes to 2 headphone jacks, each with volume control.
These output the mix bus, so the PC can't use them as outputs. Even though it can, because it does, and the interface declares itself as 6 channel, but if you try to output a signal on them, it doesn't work. 4 outputs are fine, I don't need 6, so this is a problem for another day.
Fluantz project completed!
- By Pattyt
- Analogue Source
- 6 Replies
Guess I forgot to post about this project from last winter, as when spring hits, there's tons of outside projects and toys to do and play with! Now that cold and rain is here, its back indoors, and back into audio bliss.....
This was a simple (as im a rookie) diy project of taking my first and only TT, moding it, and making it my own. This was given to me from my mother 3 years ago as I've always wanted to hear what vinyl is all about. As she's getting up there in age, I wanted a easy project that the two of us could do together, improve the sound a little, and make it a "permanent im not going to get another and replace this one with something better" turntable.
I love the look of my marantz gear, and thought, why don't I make my fluance rt-81, match my marantz stack?!
So, I tore apart the fluance, and took my set of decent patch cables, and bypassed the internal amp 100% (even though there's a defeat switch, it still runs the circuit through a series of resistors) and soldered directly to the tonearm wiring, also redid the grounding wiring as it was poorly done and measured high resistance. I then sourced a marantz face plate in the right dimensions and a set of feet for my project. At first I filled in all the holes with a 2 part plastic jb weld epoxy, this left, well, a rough finish, so on went the bondo, and after much sanding, and filing, and sanding, the surface was still not 100% flat, and tried the black brushed aluminum vinyl wrap, and looked horrible.
Back to the drawing board....well, got a piece of aluminum plate from Lowes, cut, sanded to correct size, wrapped with ...the....well, wrap, and looks great! Smooth, flat, factory.....ish hahaha.
Another mod I've always seen is to isolate the table. So, again, ebay and grabbed some half inch sorbethane washers x4, left the bottom cover off the fluance, and placed the washers between that and a baseboard I made out of 3 glued and screwed layers of half inch MDF, slightly wider as this base would be used to hold the front marantz panel. I installed some 1/4-20 thread inserts into the base, as I wanted the feet to be adjustable for leveling the turntable (as the stock rt-81 didn't have adjustable feet). Installed some same thread screws into the marantz feet and installed after the wrapped board, attached the front panel (after more sanding and painting) reassembled the rt-81 and placed back on top. I still need to do some finishing of white decals for the model number ( Marantz TT-81? Or TT-1950 as this was the year my mom was born?) I also changed out the cart to the ATVM95ML after many recommendations.
Results? Well, I can tell you for certain the curtain has been lifted to reveal what my "reference" system can do for high frequency, it was as though before anything over 14k hz was cut (as I have a seperate headshell for the stock cart, I can A/B them) and believe this was due to the rewire job. I also noticed that mid bass around 250 hz tightened up as the kick drum in fleetwood make "second hand news" tightened up, I believe to be attributed to the isolated base. Now, as far as the cartridge goes.....yeah, that kick drum? I can now hear definition in the thwack of that mallet? Hitting that kick drum, separation is also increased for as busy as that song is, it never gets blury or obscured with the "precision chaos".....
But above all else, I got to build something with my mother by my side, something that can't be bought, and a permanent piece to my entertainment system that won't be traded in at any time ]
This was a simple (as im a rookie) diy project of taking my first and only TT, moding it, and making it my own. This was given to me from my mother 3 years ago as I've always wanted to hear what vinyl is all about. As she's getting up there in age, I wanted a easy project that the two of us could do together, improve the sound a little, and make it a "permanent im not going to get another and replace this one with something better" turntable.
I love the look of my marantz gear, and thought, why don't I make my fluance rt-81, match my marantz stack?!
So, I tore apart the fluance, and took my set of decent patch cables, and bypassed the internal amp 100% (even though there's a defeat switch, it still runs the circuit through a series of resistors) and soldered directly to the tonearm wiring, also redid the grounding wiring as it was poorly done and measured high resistance. I then sourced a marantz face plate in the right dimensions and a set of feet for my project. At first I filled in all the holes with a 2 part plastic jb weld epoxy, this left, well, a rough finish, so on went the bondo, and after much sanding, and filing, and sanding, the surface was still not 100% flat, and tried the black brushed aluminum vinyl wrap, and looked horrible.
Back to the drawing board....well, got a piece of aluminum plate from Lowes, cut, sanded to correct size, wrapped with ...the....well, wrap, and looks great! Smooth, flat, factory.....ish hahaha.
Another mod I've always seen is to isolate the table. So, again, ebay and grabbed some half inch sorbethane washers x4, left the bottom cover off the fluance, and placed the washers between that and a baseboard I made out of 3 glued and screwed layers of half inch MDF, slightly wider as this base would be used to hold the front marantz panel. I installed some 1/4-20 thread inserts into the base, as I wanted the feet to be adjustable for leveling the turntable (as the stock rt-81 didn't have adjustable feet). Installed some same thread screws into the marantz feet and installed after the wrapped board, attached the front panel (after more sanding and painting) reassembled the rt-81 and placed back on top. I still need to do some finishing of white decals for the model number ( Marantz TT-81? Or TT-1950 as this was the year my mom was born?) I also changed out the cart to the ATVM95ML after many recommendations.
Results? Well, I can tell you for certain the curtain has been lifted to reveal what my "reference" system can do for high frequency, it was as though before anything over 14k hz was cut (as I have a seperate headshell for the stock cart, I can A/B them) and believe this was due to the rewire job. I also noticed that mid bass around 250 hz tightened up as the kick drum in fleetwood make "second hand news" tightened up, I believe to be attributed to the isolated base. Now, as far as the cartridge goes.....yeah, that kick drum? I can now hear definition in the thwack of that mallet? Hitting that kick drum, separation is also increased for as busy as that song is, it never gets blury or obscured with the "precision chaos".....
But above all else, I got to build something with my mother by my side, something that can't be bought, and a permanent piece to my entertainment system that won't be traded in at any time ]
Attachments
SSE build - power measurements
Hello everyone,
I have build my SSE with Hammond 274BX power transformer, 193J Choke and 1628SEA output transformers.
The board was very straightforward to stuff and assemble. Many thanks to George for his effort in the design of the SSE amp.
I have taken some measurements and the power numbers seem kind of low.
With new production (New Sensor Svetlana) KT88 and the following parameters:
B+ voltage: 442V
plate voltage: 430V
Voltage drop across cathode resistor (560 Ohms): 42V
Plate dissipation: ~30Watts
Using 8ohm dummy load resistors, I get ~1.5W of power in both UL and triode mode. The strange thing is that I can actually hear the 1khz test signal through the amp.
The amp sounds great otherwise.
KT-88-triode.png - Google Drive
KT-88-UL.png - Google Drive
Are these numbers in line with other builds?
I have build my SSE with Hammond 274BX power transformer, 193J Choke and 1628SEA output transformers.
The board was very straightforward to stuff and assemble. Many thanks to George for his effort in the design of the SSE amp.
I have taken some measurements and the power numbers seem kind of low.
With new production (New Sensor Svetlana) KT88 and the following parameters:
B+ voltage: 442V
plate voltage: 430V
Voltage drop across cathode resistor (560 Ohms): 42V
Plate dissipation: ~30Watts
Using 8ohm dummy load resistors, I get ~1.5W of power in both UL and triode mode. The strange thing is that I can actually hear the 1khz test signal through the amp.
The amp sounds great otherwise.
KT-88-triode.png - Google Drive
KT-88-UL.png - Google Drive
Are these numbers in line with other builds?
Sound Bar Hacks and case mods
- By dfgdfgdfg
- Construction Tips
- 8 Replies
Hi all,
I made some contributions in a projector thread about understanding the protocols for lamp ballast communication. This is a pretty great community. I'm not a sound engineer, so I might be wrong and looking for input.
I am building an amp from the guts of a soundbar LG LAS160B.
This is going to be detailed, so please don't be deterred by the length of the post. There is a photo and the details are there to spare people's time.
https://postimg.cc/9w5HHqX6
Background:
I was not happy with the casing of my sound bar as it seemed to be deteriorating. So I salvaged the guts of it for use later. The sound used to reach about 85-89dB at max volume, subjectively from 3m away or 10ft indoors. Never really got loud enough to enjoy much and seriously lacking in bass and a lot of compression past 12kHz although I could hear some 14kHz come through.
I made some contributions in a projector thread about understanding the protocols for lamp ballast communication. This is a pretty great community. I'm not a sound engineer, so I might be wrong and looking for input.
I am building an amp from the guts of a soundbar LG LAS160B.
This is going to be detailed, so please don't be deterred by the length of the post. There is a photo and the details are there to spare people's time.
https://postimg.cc/9w5HHqX6
Background:
I was not happy with the casing of my sound bar as it seemed to be deteriorating. So I salvaged the guts of it for use later. The sound used to reach about 85-89dB at max volume, subjectively from 3m away or 10ft indoors. Never really got loud enough to enjoy much and seriously lacking in bass and a lot of compression past 12kHz although I could hear some 14kHz come through.
The old specs:
There was one rectangular "racetrack" full-range driver per channel in this 2.0 system 40mm x 100mm or 1 1/2" x 4". There were places for tweeters to go in and online tear-downs had tweeters, but mine came without any and there was nowhere to plug them in and no crossovers, although a lot of empty room in the driver compartments.
My thinking:
The first watt of power is the most important. I felt like LG did something amazing with their DSP and enclosure to manage to get the range they did out of these little speakers. I think the excursion was pretty high. I wanted to test my theory for myself and others. I play guitar a bit and close to a lot of musicians, so I kinda lamented the sound experience with TVs. Like we gave up on a century of speaker development to have these sleek bars. They sure look good and can be good if you get really expensive ones with a ton of engineering in them. But fighting against physics is hard. So my idea was to use some bookshelf speakers with the amplifier only of the sound bar and have the niceties of bluetooth when I'm lazy and optical in etc for permanent connections.
So I only need 1W of power to get 81 dB of sound right at 1m? Didn't feel like it at all. But I went with the stated numbers. 25W per channel of output power suggests about 14 dB of gain. This should bring up the volume to 95dB. Listening from 10 feet away drops this by say 9 dB but there was 3 dB of room gain, so a final 89dB. This is what I think I was hearing so I thought I could keep running with these numbers. So I just had to build it out into a nice chassis and choose some speakers to go with it was my hope.
New (to me) speakers:
Since this is a test setup, I wanted to try it on some speakers I'm not too attached to. I gave away my Panasonic SA-PM25 speakers years before, but they were pretty ok. Nvm. I found some cheap old Sony SS-CMD373 speakers x2 on eBay for the test. They were not damaged and the resistance matched the stated impedances. I know impedance and resistance are not the same thing.
Each one is/has:
Calculations:
So, for these new speakers with the LG Amp, the first watt should get me say 88dB at 1 m.
The gain of the amp should be 14dB as before at full volume, but scaled due to impedance difference.
Since the impedance scaling is a factor of 4 ohms / 6 ohms, the power into 6 ohms would now be 25 x 4/6 = 16.7W.
This is worth 12dB.
So at full volume at 1m distance, the volume should be 100dB.
Making adjustments for the 3m listening distance and room gain brings this to 94dB.
Did it work?
Sure it makes a sound. The bass was ridiculously high at low volume on the remote. I had to eq -12 dB on the bass band of 60-100Hz on my android eq. That and add about 4 dB to each of the other bands brought it close to balanced. So now I could turn up the volume. The LG remote has a range of 40 button presses from min to max. At about level 16 up from 0 the amp was going into an undocumented protection procedure and flashing a red light. Power cycling and reconnecting would solve it. This is where I started scratching my head. What was going on?
It feels like I'm not even getting past the first 1W of power!
Diagnostic:
So I am absolutely surprised why some kind of protection circuit is kicking in at 14 steps out of 40 on volume.
What could be happening?
Ohms law suggests that the current would be lower with a higher impedance.
With the original 4 ohm load per channel, I = 14.5 V / 4 ohms = 3.6A equivalent to 52W which is double the rated capacity. These speakers never clipped at max volume.
With the new speakers at 6 ohms per channel, I = 14.5 V / 6 ohms = 2.4 A equivalent to 34W which is also higher than the amp capacity.
The buck converter chip AP6503 has a 3.5A current limiter at which point it drops to 70% output to protect the amp chip. This seems to make sense. So it should never stop at 2.4 A with the new speakers. At worst the output should drop to 70%.
The amp chip is TAS5733L. Its a 4 channel digital input amp 10W per channel at 10% THD. LG combined two channels to make one left, and the remaining two to make right. This made it 20 W per channel. Then they upped the PSU voltage to 14.5 to get it to 25W which is accepted practice on the datasheet, up to a max of 16 V.
This chip locks out if the voltage sags to 5.4V. There is a decent input supply capacitor on the 14.5 V supply, and an unpopulated spot for another. I doubt the voltage could sag that much when the speakers are limiting power consumption to less than the original amount.
There is an Automatic Gain Limiter function I don't really know about.
Why am I hitting any limits at all? Is there something about load impedance I am missing after a week of obsessively reading about this?
I look forward to your ideas. Sometimes it's something obvious. Sometimes not.
There was one rectangular "racetrack" full-range driver per channel in this 2.0 system 40mm x 100mm or 1 1/2" x 4". There were places for tweeters to go in and online tear-downs had tweeters, but mine came without any and there was nowhere to plug them in and no crossovers, although a lot of empty room in the driver compartments.
- SPL: 81 dB
- Bass Reflex (but there were no ports for this or passive resonators)
- Impedance: 4 Ohms (actually this was measured off-state resistance but quoted as impedance)
- Unshielded.
- 25 + 25 W Amp.
- 14.5V SMPS at about 5A.
My thinking:
The first watt of power is the most important. I felt like LG did something amazing with their DSP and enclosure to manage to get the range they did out of these little speakers. I think the excursion was pretty high. I wanted to test my theory for myself and others. I play guitar a bit and close to a lot of musicians, so I kinda lamented the sound experience with TVs. Like we gave up on a century of speaker development to have these sleek bars. They sure look good and can be good if you get really expensive ones with a ton of engineering in them. But fighting against physics is hard. So my idea was to use some bookshelf speakers with the amplifier only of the sound bar and have the niceties of bluetooth when I'm lazy and optical in etc for permanent connections.
So I only need 1W of power to get 81 dB of sound right at 1m? Didn't feel like it at all. But I went with the stated numbers. 25W per channel of output power suggests about 14 dB of gain. This should bring up the volume to 95dB. Listening from 10 feet away drops this by say 9 dB but there was 3 dB of room gain, so a final 89dB. This is what I think I was hearing so I thought I could keep running with these numbers. So I just had to build it out into a nice chassis and choose some speakers to go with it was my hope.
New (to me) speakers:
Since this is a test setup, I wanted to try it on some speakers I'm not too attached to. I gave away my Panasonic SA-PM25 speakers years before, but they were pretty ok. Nvm. I found some cheap old Sony SS-CMD373 speakers x2 on eBay for the test. They were not damaged and the resistance matched the stated impedances. I know impedance and resistance are not the same thing.
Each one is/has:
- 5 1/4" Woofer
- 1" Tweeter
- Impedance: 6 ohms
- SPL: 91dB is my estimate based on comparing 3 driver specs of the same type and averaging. Crude, but not a bad starting guess. The Panasonic speakers I gave away had 86dB and were 1" smaller drivers. For the purpose of calculating I guess we could estimate it to be 88dB at the low end.
- Frequency response about 40 Hz - 20kHz comparing it by ear to other speakers I have. Maybe goes a little lower. My phone app SPL meter shows activity around 30Hz but low amplitude.
Calculations:
So, for these new speakers with the LG Amp, the first watt should get me say 88dB at 1 m.
The gain of the amp should be 14dB as before at full volume, but scaled due to impedance difference.
Since the impedance scaling is a factor of 4 ohms / 6 ohms, the power into 6 ohms would now be 25 x 4/6 = 16.7W.
This is worth 12dB.
So at full volume at 1m distance, the volume should be 100dB.
Making adjustments for the 3m listening distance and room gain brings this to 94dB.
Did it work?
Sure it makes a sound. The bass was ridiculously high at low volume on the remote. I had to eq -12 dB on the bass band of 60-100Hz on my android eq. That and add about 4 dB to each of the other bands brought it close to balanced. So now I could turn up the volume. The LG remote has a range of 40 button presses from min to max. At about level 16 up from 0 the amp was going into an undocumented protection procedure and flashing a red light. Power cycling and reconnecting would solve it. This is where I started scratching my head. What was going on?
It feels like I'm not even getting past the first 1W of power!
Diagnostic:
- I tried one speaker at a time with similar results.
- I tried 8 ohm speakers which could be turned up without hanging the amp. But low max volume.I checked and resoldered the cables.
- I added an aluminium heatsink to the DSP and a big one to the amp chip. Measured that most of the circuit board was 26 degrees C in a 24 degree C room (79 F in a 75 F room). The amp chip got to 56 C or 133 F.
- The system is passively cooled, with a lot of air vents and a steel case. The heatsink itself reached 25 C at the tips, so was more than enough and I used thermal paste and it was screwed down firmly to the chip.
- The voltage buck converter didn't get hotter than the PCB.
So I am absolutely surprised why some kind of protection circuit is kicking in at 14 steps out of 40 on volume.
What could be happening?
Ohms law suggests that the current would be lower with a higher impedance.
With the original 4 ohm load per channel, I = 14.5 V / 4 ohms = 3.6A equivalent to 52W which is double the rated capacity. These speakers never clipped at max volume.
With the new speakers at 6 ohms per channel, I = 14.5 V / 6 ohms = 2.4 A equivalent to 34W which is also higher than the amp capacity.
The buck converter chip AP6503 has a 3.5A current limiter at which point it drops to 70% output to protect the amp chip. This seems to make sense. So it should never stop at 2.4 A with the new speakers. At worst the output should drop to 70%.
The amp chip is TAS5733L. Its a 4 channel digital input amp 10W per channel at 10% THD. LG combined two channels to make one left, and the remaining two to make right. This made it 20 W per channel. Then they upped the PSU voltage to 14.5 to get it to 25W which is accepted practice on the datasheet, up to a max of 16 V.
This chip locks out if the voltage sags to 5.4V. There is a decent input supply capacitor on the 14.5 V supply, and an unpopulated spot for another. I doubt the voltage could sag that much when the speakers are limiting power consumption to less than the original amount.
There is an Automatic Gain Limiter function I don't really know about.
Why am I hitting any limits at all? Is there something about load impedance I am missing after a week of obsessively reading about this?
I look forward to your ideas. Sometimes it's something obvious. Sometimes not.
Calculating driver inductance from Limp
- Multi-Way
- 76 Replies
To know the inductance at 1 kHz looking at the graph of the SB Acoustic with Limp it measures aprox. 9 ohm which is a 1 ohm.
1 ohm / 1000 Hz = 0.001 / 2Pi = 0.00159H = 0.159mH
Have I done well the calculations?
TIA
Felipe
1 ohm / 1000 Hz = 0.001 / 2Pi = 0.00159H = 0.159mH
Have I done well the calculations?
TIA
Felipe
New circuit diagram for Alpine dlx-f2nw (ddlinear crossover)
Need circuit diagram for Alpine DLX-F17s crossover network circuit diagram
Looking for circuit diagram of Alpine DLX-F17s crossover network circuit diagram...
Looking for circuit diagram of Alpine DLX-F17s crossover network circuit diagram...
Aksa Lender M2X format for LuFo
I just got the new Aksa Lender preamp PCBs in M2X format with built in sub-mezzanine DCDC switching PSU that makes 55v for driving the LuFo amp.
Thank you JPS64 for another great layout. The preamp level is all TH and the PSU level is mostly surface mount as they don’t make DCDC converter chips in TH.
Boards are 1.6mm and ENIG finish.
Thank you JPS64 for another great layout. The preamp level is all TH and the PSU level is mostly surface mount as they don’t make DCDC converter chips in TH.
Boards are 1.6mm and ENIG finish.
Attachments
Repiar Mission Cambridge AMP.
- By freemanfung
- Solid State
- 0 Replies
Hi, I just got a defective Mission Cambridge integrate AMP. I searched for the WEB but cannot find details circuit diagram for this AMP. It seems the model is Mission Cambridge 778 .....
Does anybody help ?
Does anybody help ?
"Tube health" Anxiety Caused By Using My Amplifier
- By zastin17
- Tubes / Valves
- 32 Replies
So something has been really driving me crazy while listening to music. And I know its not supposed to be like this.
And that is using my Tube Amplfier, and finding myself way overally worrying about the tubes on my Dynaco St-70. (Which I fully restored)
I love the sound, and I love everything about tubes and I'm a bit "emotionally" Obsessed with them and get attached. In terms of music and the enjoyment they do give me.
But I am having a very hard time just simply enjoying the amp without thinking about every second I use it, (apparently these amazingly georgious tubes inch closer to death.
I don't want to worry about such things while trying too enjoy music. I Just want use it and enjoy it.
I have my Mullard XF3 Blackburns and 7199s Which came with my stock Dynaco St-70.
I love these tubes and think they are absolutely georgious in sounds and looks!!! I got them tested aswell. 78/100 which is about where new tubes test on my Tube guys tester. He said they are very strong great tubes! And where used on this amp seamingly since the beginning.
And want listen too them, but don't want them to die either..... They are obviously at this point, unobtainable for the unwordly prices they go for. Over $2000 for a quad. And are obviously not made anylonger. I did not pay anywhere near that for the entire amp, ile tell you that mutch. It needed restoration however.
It's hard for me to get passed that thought while just wanting to listen to music, I want to relax in the music, not stress about its health of the amp.
I have a Bucking transformer for AC line too 115VAC from my higher 120-124v, and always Biased too around 1.42V. So this amps transformer stays very cool. Am I overthinking this?? I mean there are people still rocking their original tubes in their st70 from the 60s. And then I read people replacing tubes nonstop and eats them for breakfast.
But I have all these tubes, and I think about it in my head and go "So in 10x years all these beautifull tubes will all be garbage?" I can't take that thought that this beautifull amp may destroy itself.
How can I get past this nonsense so I can just listen to music and enjoy it like its supposed to be enjoyed?
My rectifier is a 5AR4 Matshushida also on the amp when I got it, which apparently may outlast me.
I listen to this amp all the time. Everyday. So I am a bit worried about these Mullard Xf3 Tubes.
Some of the things I've done to this amp include:
Replaced Bias pots with the nicer replacements. All capacitors replaced, Gold RCA Jacks I modified to fit using the original brown mount.
New Bias resistors, capacitors, and the old selenium diode bypassed aswell with silicon 1N4007 1kv.
And replaced the 75v 50uf caps with 100uf,200v.
And that is using my Tube Amplfier, and finding myself way overally worrying about the tubes on my Dynaco St-70. (Which I fully restored)
I love the sound, and I love everything about tubes and I'm a bit "emotionally" Obsessed with them and get attached. In terms of music and the enjoyment they do give me.
But I am having a very hard time just simply enjoying the amp without thinking about every second I use it, (apparently these amazingly georgious tubes inch closer to death.
I don't want to worry about such things while trying too enjoy music. I Just want use it and enjoy it.
I have my Mullard XF3 Blackburns and 7199s Which came with my stock Dynaco St-70.
I love these tubes and think they are absolutely georgious in sounds and looks!!! I got them tested aswell. 78/100 which is about where new tubes test on my Tube guys tester. He said they are very strong great tubes! And where used on this amp seamingly since the beginning.
And want listen too them, but don't want them to die either..... They are obviously at this point, unobtainable for the unwordly prices they go for. Over $2000 for a quad. And are obviously not made anylonger. I did not pay anywhere near that for the entire amp, ile tell you that mutch. It needed restoration however.
It's hard for me to get passed that thought while just wanting to listen to music, I want to relax in the music, not stress about its health of the amp.
I have a Bucking transformer for AC line too 115VAC from my higher 120-124v, and always Biased too around 1.42V. So this amps transformer stays very cool. Am I overthinking this?? I mean there are people still rocking their original tubes in their st70 from the 60s. And then I read people replacing tubes nonstop and eats them for breakfast.
But I have all these tubes, and I think about it in my head and go "So in 10x years all these beautifull tubes will all be garbage?" I can't take that thought that this beautifull amp may destroy itself.
How can I get past this nonsense so I can just listen to music and enjoy it like its supposed to be enjoyed?
My rectifier is a 5AR4 Matshushida also on the amp when I got it, which apparently may outlast me.
I listen to this amp all the time. Everyday. So I am a bit worried about these Mullard Xf3 Tubes.
Some of the things I've done to this amp include:
Replaced Bias pots with the nicer replacements. All capacitors replaced, Gold RCA Jacks I modified to fit using the original brown mount.
New Bias resistors, capacitors, and the old selenium diode bypassed aswell with silicon 1N4007 1kv.
And replaced the 75v 50uf caps with 100uf,200v.
