For a long time I wanted to try one of Seas midwoofers, U18 seemed to be well balanced for midwoofer duty in 2way, though there was not many good measurements available from which I could judge the driver. D2604 limited edition discovery tweeters got to my hands, and I have to ay I like them a lot, at least the measured performance for now.
U18: I am very please with its FR linearity. It is very easy to work with a to make a crossover.
Initial crossover is attached, and in coming weeks I will optimize it and arrange the first listening tests.

More details: https://pkaudio.webnode.cz/u18d2604/

Troy Crowe, whose building my speakers, recommended this book https://shop.shakeandco.com/book/9781138921368

But none of my local public libraries have it and I don't know how math intensive it is to even think about buying it,

Can anyone recommend another book and/or ONLINE sources, BUT essentially for dummies-or at least math challenged dummies?

Hello to all - new to the forum, and I have a very difficult problem on my hands!

After installing new load tray belts in a Denon DCD-2560 single CD player from the early 1990's and after testing it with a few open/close cycles. the drawer failed to open. Inspection showed that the gear that moves the entire rack back and forth had broken - not just a crack, but a section of the gear broke away. Luckily all teeth are still intact, and it fits back together correctly.

The tricky part with this gear is that is uncommon - it has 7 teeth and is rather small, and is made out of nylon/delrin plastic. I tried to super glue the gear back together and let it cure overnight. This worked for about 100 open/close cycles, but eventually the gear didn't hold together. It's very difficult to glue this type of plastic, as much searching/reading has shown.

I'm looking to see if anybody has thoughts/ideas on how to get a replacement gear for this unit - many hours of searching have turned up 0 results. As well I'll consider having a gear 3D printed, but most of the online tools available to create a custom gear have a minimum requirement of 8 teeth on the gear. I know it may be possible to send the gear in, but I do want to keep costs under control in this situation.

As well if anyone has thoughts or experience on actually repairing nylon gears of this sort it would be greatly appreciated for any ideas! Thanks in advance!

Outside diameter of the gear is 9.75mm - hard to measure as no even number of teeth, but that's after many tries with the caliper.

I want to make an imaginary and virtual toast together with all those people like me who don't want to give up in the face of the many problems that one encounters when one dedicates oneself to study and design in the audio field. when you start you are amazed because you discover an unexplored world then as you delve deeper into the topic many problems arise and you have to work hard to understand how to solve them. These difficulties are precisely the beauty of life because they encourage the brain to come up with a solution.
so cheers

If you have one that you are looking to part with let me know. Thanks!

in a swapmeet thread ( see here ) there was some debate about benteng, bonens and bochen presets.

some time ago, i used four bochen presets, and one was difficult to adjust ..... i.e. faultly.

so i broke one open.

Lots of either love or hate for these things. I’ve never heard them either the originals or the these new reissue units…..Price for a pair is reasonable though at $250 including mounting hardware…….hmmmm.

MEH speakers look pretty neat! Many of them seem like more output (+ expense) than I think is necessary for my space, so I'm considering a 2 way with a 2" and an 8". I have a sub to take care of the really deep stuff. I do sort of enjoy the conceptual "Wow! / Meh" juxtoposition.

I've kinda wanted to do a 2-way with a 2" FR as a low tweet for a while, but they're so low efficiency. I started thinking about wave guides for the tweeter, but then thought maybe it should be a MEH. The idea being to increase sensitivity on the 2" down to 500 Hz or so, and cross to the 8" between 500 and 1k, and hopefully keep the horn size domestically compatible. I have active / DSP available, but would like to be able to make a passive XO for it.

These are some buyout drivers I got a while back. These drivers are NLA
2" - Tymphany TC6FC02-04
https://www.parts-express.com/Peerl...ll-Range-Line-Array-Drive-264-1350?quantity=1

8" - DynaLab V22-DR-0003
https://www.parts-express.com/DynaLab-V22-DR-0003-8-Poly-Woofer-4-Ohm-299-4004?quantity=1

So I started to monkey with HornResp. I don't really know much about HornResp, so we'll see if the brain trust thinks I've done it right...




I started out trying to enter T/S directly, but that seems a little wonky and the T/S wizard seems better.

It looks like the MEH wizard simulates response like this... (2")

(and 8")


So, questions.

• Have I done a reasonable job setting this up? I might wish for more HF extension from the 8", but I think it has to be some 11 cm down the horn given it's diam. I think these dimensions makes 27 deg center-to-wall, or 54 deg wall-to-wall for the horn, and 40 / 80 deg for the end flare to smooth the horn exit (square horn shape). Am I missing any best practices for choosing horn dims?
• I see the power predictions for output pictured above. I didn't see any directionality prediction, is that in HornResp? Horns are all about the directivity so I was expecting something like that. On the other hand, I only specified sectional Sq Cm not horizontal and vertical dims so maybe HornResp couldn't hazard a guess. I had to make a spreadsheet to estimate horn the angles.
• That woofer null I presume comes from the wave entering the horn part of the way down, and some of it going back up the horn and then coming back down and interfering. That makes sense to me. But also the woofer front chamber and horn entrance is going to be a bandpass, right? Does HornResp have any facility to predict that, or help choose the entrance holes for the 8"? I was considering going to a different program to simulate a bandpass to investigate entrance sizes / velocity.
• HF response on the 2" falls off. 2" spec is 85 dB @ 2.8 V and basically flat to HF on-axis. Other simulators frequently show a lot of HF roll-off that doesn't appear on-axis. I'm sort of assuming that is what's going on here (total output vs on-axis?). Does anyone have experience with how real that might be?

Hmmm... anything else? I'll come back as I think of more questions / make progress...

Thx

Hi from Taylorsenior italy

Hi and thank you for having me .
I am hoping to find someone who can help me with information regarding the construction of the Castle Stirling 3's.
I have bought a pair that were damaged in a flood and I am going to refurb them .

Hello everyone,
my name is Shari. I am interested in establishing a small business in Israel that deals with commercial production of DML speakers. I am familiar with the extensive thread here about this technology, but I am lost there.
I want to initially manufacture commercial DML speakers on canvas, with the option for customers to have personalized printing. I remember some friends here who have shared their projects on canvas, and I would be happy to consult with them, but I still don't have the option for private messages.
I would appreciate it if you could advise me here, is my idea realistic from a commercial point of view, is it really possible to produce a speaker with this technology that covers a wide frequency range in high quality? If so, would a printable canvas be a good material as a panel? I would appreciate any help
Thanks in advance

I fear that I may be in the minority here, but I am a fan of using products to improve my AC, in particular the Niagara series from Audioquest. I have played with quite a lot of these devices and found some degraded the sound of amplifiers, typically MOV type units.

Nordost is a company that shuns doing anything to the power other than having really good outlets and ground.

Which ever camp you fall in I was hoping that perhaps I could pique the interest of some SMart person/people and suggest that perhaps designing a DIY power center.

I'm working on a set of bookshelf speakers (2 way) and keep running up against hoffman's iron law. I also read recently about purifi's SPK16 reference design, and they were able to get down to about 32hz, but that also had a lot of design choices that were based on the fact they have a facility to design all of these things in and a budget much larger than mine. Additionally, I'm going to use a hypex fusion amp, which means I will have an active implementation as opposed to a passive one which also opens me to much greater tuning options including things like a linkwitz transform.

With all of that said, purely from a performance perspective, would it be more advantageous to use passive radiators, or just add subwoofers on the sides and make the design a 3 way?

As a many years happy user of TPA3255, I thought it might be a good time for an upgrade. So here it is:




It's a dual mono, PBTL, single power supply design with PFFB. 12V is generated internally with two LM5017. It uses standard heatsinks available from Mouser:

https://www.mouser.be/ProductDetail/984-ATS-TI1OP519C1R3

but they do need to be shortened at one side to fit them both on PCB.

Board is 4-layer 10x10cm standard thickness. Coils are CoilCraft SER2918 mounted vertically.

Hello DIY forum,

I have plans to build high efficiency LCR speakers and I'm looking at SB Audience and Faitalpro units.

Bass doesn't need to dig really deep as I already have a dual LLT B&C 21SW152 subwoofer tuned @11Hz and a sealed corner sub with 4x Visaton TIW400 with QTC = 0.6

Left, center and right channel will all include:
Woofer: 2x SB Audience NERO-12MWN400D sealed with QTC = 0.6
Mid: 2x SB Audience ROSSO-6MW150D sealed with QTC= 0.5
Treble: Faitalpro HF10AK on RCF H100

Crossover frequencies will be approximately 250Hz and 1500Hz.

I could consider to replace the SB Audience Nero-12MWN-400D with a ROSSO-15MW500 for a slightly better response under 100Hz.

Amplification and filtration will be done with the Hypex FA253 (Or FA503 if that one handles lower impedance better). I'll use a 2nd order passive crossover on the HF10AK for additional protection. Measurement will be done with REW.

All units will be built into a TV wall with sturdy bracing to avoid resonances. The 12"/15" woofers will be built into the lower cabinets that get extensive bracing + double panel thickness. The mid woofers will also get sturdy enclosures with non parallel walls. The center speaker will be built into the lower cabinet under the TV and the L-R speakers might be built into separate cabinets that stand on each side of the TV. If I succeed this will be an extremely powerful home cinema system with very clean and non-technical look.

Who has experience with the above mentioned SB Audience woofers or alternatives? Who sees a fatal flaw reading all the above? I'll certainly post images when the build starts and I'm open for all criticism.

​

So I have an older Omnitronics 2220 turntable. It’s a typical direct drive ‘DJ’ turntable.
However at some point since I have owned it, the pitch slider has ‘broken’. The TT still plays at the correct speed at 0, but if I move the slider up or down…. The speed increases (instead of increasing one way and slowing down the other).
I’ve had a look inside and can’t see anything obviously wrong.
There is some information on the turntable here, but not sure it helps me much.
Anyone able to suggest anything?! Thanks!

Hi, there. I'm selling TDA1387 and TDA1543 DAC HAT KIT. Soldering and assembly are required. The KIT contains both thru hole and three SMD1206 resistors. This already contains a TDA1387 x8 module. TDA1543 x2 module is sold separately.

Introduction:

• This is a DIY I2S DAC HAT for Raspberry Pi. Without the need for USB / COAXIAL / TOSLINK signal conversion, this DAC is driven by the I2S signal pins from Raspberry Pi directly, simple yet effective.
• TDA1387 is a 16-bit multibit DAC. Although this DAC was introduced in the 90’s but the sound quality can beat most of the modern DAC with proper design.
• The components of this DAC HAT are carefully selected and of high quality. With proper power supply, this DAC HAT sounds warm, transparent, musical, rich, detailed, relaxed, and analogue. The bass response is surprisingly deep and punchy.
• This DAC HAT can work with Raspberry Pi alone and is natively compatible with STEALTH V3. LPS is recommended when used with Raspberry Pi alone.
• Select HifiBerry as the output device under the device setting.

Specification:
-Accepts 16/24/32 bits*, 44.1/48 kHz
-Output Level: 2Vpp
*Only the most significant 16bits are processed, other bits are truncated.

Disclaimer:
-TDA1387 is an very old IC and not in fabrication anymore. The TDA1387 IC on the module is either from old stock or disassembled. Although the module is sample checked, the quality cannot be guaranteed. Refund of this IC module is not accepted if it is found faulty upon arrival. Please consider buying the basic kit without TDA1387 if you do not accept this clause.

Price Options:
-Complete kit (TDA1387 included): HKD700
-Basic kit (TDA1387 excluded): HKD650
-Finished good (TDA1387 included): HKD830
-Shipping fee incurred depending destinations

YouTube demo:
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I have been given ann Eva 1 LDR remote control preamp, single RCA inputs and outputs. But it came without a wall wart power supply.
Anyone know what voltage and current rating the PS should be?
Also, which is the input and output pair?
Guessing inputs on the outer side, outputs towards the middle of the back of the enclosure.
Hopefully the balance is okay. LDRs tend to drift with time, it has been my experience.
Thx in advance for any assistance.
Cheers
Luigi

Hi guys.
I need to test some 2SC1584 transistors. They come from an older power amp, used in the power supply (+52v, - 52v and ground). There was a pop noise in this amp exactly where these transistors were placed and the amp stopped working. They somehow still check OK when testing with a multimeter.
My question is: I have another 24v power supply with a 2N3055 and it works. Since both transistors have the same pinout and similar datasheets, I was wondering if I could just switch these Transistors in order to see if they still work.

Can anyone point me to the Ayumi pctube library? I appreciate the help.

If anyone has them laying around, let me know.

Howdy, was curious if anyone had any drawings for the BMR TEBM46 or some on baffle. Found a CNC shop near by that will do what I want for cheap, but I need something to give them. They requested a dxf file.

I asked yamaha support to replace the pcb power supply and they tells me
they stopped the manifacture
So and idea to find somthing else for replacing ?
I have the pcb and i see blows up the transistor burned and some diodes
Have some one else the same problem or someone knows somthing simmiliar like sw800 pcb psu to replace it?

Thanx alot Bill

Can anyone point me to accurate LTspice models? I'm specifically looking for 7591 and 7199

Hello guys. Bouth these modules and assembled in a case from audiophonics. I will redo the internal wiring, I dont like it.
I hooked it up to a source playing sin wave signal at 1kHy. I get 1.12V out of the source (SFF pc, Im in a hotel on a business trip). The preamp has 5 gain stages.
The toroids are 15-0-15 each. Opamp in preamp is NE5532P and in converter JRC4580DD.

When I set the gain to LvL0, I measure 2.54V on the preamp out, and about 3.8V from the converter when volume set to 0dB.
At gain LvL1 its 4V and 5.6V when set to 0dB
At gain Lvl 2 higher and then at LvL3 even more.
At Lvl5 I have almost 8,7V on the converter out to XLR. However, at LvL4 its 9.56V

Is the Muses module broken? Why such high voltage? I want to use it with a Hypex UcD180 power amp that will be build once I get home.

I have no experience or knowledge building preamps :d thats why I chose the modules. I thought just put it together and all will be fine.

Danny

Looking for a pair of Infinicap signature series for preamp coupling, Partsconnexion used to sell this but not any more, found nowhere available. Any one have an idea? Thanks in advance🙏

I’ve seen many discussions on here for the search of SMPS power supplies which are good.
even threads on measuring them.
but not a list of good ones to buy

does anyone know of any 5V around 5A good SMPS which are reasonably priced?


thanks In advance !

Nexperia has brought out matched pairs NPN and PNP, Hfe matching up to 0.98, diff voltage to 2mV. for example PMP4201, PMP5201. for thos who like to bake their own opamp.

Hello.
In case You'd like to liquify Your Radians LM10n i'd gladly consider making it happen. Send me PM with proposal and link to photo album.

Dear all,

I have an old tube radio (schema: https://gejoweb.wordpress.com/x-philips-b5x43a-schema/), with singe end EL84 output.

Now I would like to change the original output transformer into Lundahl LL2765, and used it in the line-in mode as a headphone amplifer (https://www.lundahltransformers.com/wp-content/uploads/datasheets/2765.pdf), given the output impedence for EL84 is around 5k.

My questions are:
1. Is it worthy to do so, given the old architecture of the original schema? Or it is a good idea to DIY a new one with the pair of LL2764?
I am also interested to know the possibility of reusing LL2765 for 300B.
2. What is the output impedence for 300B? I checked online, and got answers from 3k to 5k. What is the best performing impedence range for 300B?
3. Would LL2764 be a good fit for 300B?

Thank you.

Yes, as in Detroit, Detroit! Not the suburbs.

Before our move to Michigan, I was located in Lowell, Massahusetts. I spent a lot of time collecting and restoring vintage hi-fi and building a system that I was pretty content with. After our move, my wife and I were pretty tied up with working on our house. It was built in 1933 and contains a lot of original features–something that we really wanted as we both love architecture and the overall build quality of old homes. Now that a lot of our restorations are complete, I've been bitten by the hi-fi bug again.

This time though, I'm much more interested in DIY builds, specifically SETs.

Also interested in hockey, baseball, knitting, sewing, the Arts & Crafts movement, cats, etc.

I have an application which requires that an audio signal be limited to 2mVpp. After 2mV level, I want the signal to clip. Under 2mV, no clip. I have an opamp in the circuit, and can use this opamp as part of the clipping circuit. When the signal is below 2mV, the clipper circuit must not interact in any way with the signal. I'm looking at a diode clipper, etc.. Does anyone have an opinion on the "best way" to do this?

Hi,

I'm currently repairing a Yamaha YST-SW800 subwoofer and have found some of the Mos-Fets to be dead but am unable to locate the ones that i require.
This is what the service manual says and the parts that i need-

Q16- V5877200- FET- 2SK2378
Q18- V5877200- FET- 2SK2378
Q19- V5877000- FET- 2SJ406

Are there alternatives to these?

Greetings, obligatory welcome message. Electrical Engineer from Australia currently working in medical imaging repairing CT, MRI and such. Old musician with tons of audio experience on the technical and performance side. Cheers

I found a B77 that I am currently restoring.
I have a collection of tapes I bought used many moons ago, but I'm not sure which ones they might be.
It would be useful to know so I can set the bias and EQ accurately.
Do these pictures help?

Hugo

I'm working on a restored Heathkit AA-100 Amp. It worked well for about 3 months but now blows a fuse every time I turn in on. I'm sure I'm going to need some help.
Based on the few minutes I've spent looking at it; the problem appears to be in the output stage (PP - 7591 biasing). But that's as far as I've gotten. It's been years since I've worked on a tube amp. I restored a Heathkit SA-2 Amp that has been working well for almost a year. I'm hoping to build or restore additional amps in the future. I look forward to participating in the forum.

Has anybody else had fun poking around a tube amp with a "Mr. Carlson Super Probe"? (an extremely sensitive non-contact signal tracer and noise finder that uses a small speaker to create an audio output.) I picked one up to troubleshoot noise issues. Maybe I'm misunderstanding its utility, but for devices prone to intermittent noise--like DIY tube amps--it could be an awfully easy way to differentiate between a troublesome resistor, dirty tube pins, a bad solder joint, etc.

I see folks have recommended cheap sniffers in other threads in the past, but the "noise" feature here seems pretty clever. If this is a terrible idea, I'll be curious to hear how!

My first impression is that it works like magic. I assume that because of its sensitivity, what it picks up may or may not make a difference in the actual amplifier performance. But it is fascinating to hear the noise generated in a power supply or even just near AC input wires. Amusing that different devices in my house seem to pick up different radio stations. Even if you are slick with a 'scope (I'm not) hearing can be more fun than seeing.

I had already found the problem I bought this to trace by just continuing to throw parts at it (bad pot in a bias circuit, ultimately). But if what it picks up means anything, my Coleman regulator board is just far enough away from the HV rectifiers on this amp on one side, while the twisted pair of AC running to the switch is probably too close on another. And either way, what a difference a bit of aluminum tape makes, at least for goofing around purposes.

I thought this would just be for when I have problems. But the next time I build, I might use this to play with chassis layout for noise purposes before I start cutting holes. And now, I feel compelled to line these wood chassis with the aluminum tape like the tin foil hat crowd. But I'll try to not get carried away.

Paul
(See Login to view embedded media )

If I keep the tube in Class A (OP in pic), will it sound any good ?

Because the anode swings near 0ma, and the grid swings close to 0V, I wonder how it will sound? (without A2 / MOSFET source follower etc)

Hi there

Is there someone can make a DIY power supply for the vintage Cello Audio Suite please?

I find myself confronted with a Quad 44 preamp. Unfortunately the owner was exposed to a similar unit which a now steadfastly retired friend had "done up" and customer wants the same "magic" worked on his unit. What he (Chris) did :
1: Replaced the TLO71 opamps with SSM2134 corksniffers These being low offset enabled him to rip out the coupling caps.. 2: Replaced the output opamps with AD845s to give a bit of drive capability 3: Replaced the CD4066 input switch matrix chips with little relays and driver transistors on homebrew daughterboards. 4066s are rather hideous distortion wise.
Chris DEFINITELY cannot be persuaded to do another one. The 2134s are obsolete and the 845s are hideously expensive. there is a corksniffer 4066 made by Maxim which may save me from CADing up some PCBs. Any suggestions for alternative currently available components before I run screaming from this job?.

Looking to learn D/A in detail & build my own user streaming platform with DAC and whatever else I can afford to throw in. Olde fart semi-golden ears, who needs quality streaming platform - theory & practical. Built Linux boxes, online since '95, engineer but not EE, semi-retired, not much extra $ these days.
Happy with old school CDs through very solid old Adcom and Vandersteens, but time to join 21st century. All music styles, mainly 20th/21st cent classical + dancehall reggae, Cockburn, Mould, St. Vincent, etc.) I listen to the equipment to hear the music, not vice versa as many "audiophiles," i.e. own supercars but couldn't drive Nürburgring. ;-p or tell a bass clarinet from a contrabassoon. i.e., I love BIS Records-Robert von Bahr, full dynamic range, true acoustic recordings, incredible site & studio sound engineering. Two ears, use them! Any ref suggestions much appreciated, the net ain't what it used to be, superlibrary becoming dismal click-count swamp. Sorry for the spew! 😱😜😁
Also an Aspie and follow general science(fusion & superconducting,) engineering, physics, Earth aka Mother, collect minerals, SE Asian & Mediterranean cooking, fermented beverages, & altogether too much.

I bought an AKAI 4000DS MK-II new in the 1970s and it worked well for many years. but hasn't been used in the last 5 years. I tried it yesterday and the take-up reel wouldn't rotate. I viewed some youtubes showing repair of this reel to reel and learned that worn idler wheels can be the cause. I took the cover off and found the rubber is hardened and worn, and bought new wheels. The AKAI youtubes showed various parts being replaced but didn't show or give any info on lubrication. Regarding the idler wheels, one has a nylon bushing, and one has a brass bushing and both spin on stationary steel spindles. My question is would the idler wheel with the nylon bushing not need lubrication and the one with the brass bushing need lubrication? The photo shows the idler wheel system design that the 4000DS MK-II used. The idler wheel bushings changed over time...somee used nylon and some used brass bushings.
Thanks

Selling 1x pair of Altec 4722 SUTs

38ohm and 150ohm taps on the primary, 50k on the secondary
Great for Denon DL103

SOLD

The title says it all 🙂 Bought a very cheap used subwoofer and I'd like to make its auto standby more "sensitive" and shut off the sub after a longer period of time

I have an adjustable regulated 10A DC power supply, that I'm using right now for heaters of 300b tubes. It works, but both 300b end up with common cathode as they are connected in parallel to the PS. What would be the best way to "isolate" them? Would a Schottky diode and a capacitor do the trick? It will have a small voltage drop, which I can adjust for in the output of the PS.

I've been playing with simulations of my speaker's crossover responses in VituixCAD. My speaker is Braun LS200.

I discovered a weird result when the polarities of all drivers were set following the factory setting (TW/MR/WF = -/+/+), the response curve was non-linear. But, when I flipped the polarities of the midrange and tweeter in order to bring them to what a traditional 3-way system be (TW/MR/WF = +/-/+), the response curve became (nearly) flat. So, what does it mean?





However, I can say that the factory setting doesn't produce bad sound at all; in fact, the Braun LS200s are the twin of the ADS 1590 speakers, and both of them received many positive reviews and also some awards.

Anyway, I have an idea what if I were to add a switch on the woofer's crossover in order to alter the responses between having EQ (the contour curve generated by factory setting) and flat response. What do you think about it?

Hello,

So I know this forum since long, as I have been an audio enthusiast all my life and I could find some useful information here. Now I am an electronic engineer and I am learning about DSP and audio device firmware etc. so I decided to make an account here to share and get some info from diyAudio folks.
I am now trying to implement QCC qualcomm audio bluetooth chips into a DSP project that is quite large, and I hope to get some help from more experienced people that have been into it for years.

Not much more to say, let's see what new exciting projects come to the forum!

I'm a fun of the British sound and I've been delighting my ears for almost 35 years with an Exposure amplification system and a pair of Rogers studio 1a.
Unfortunately recently the exposure vi power supply irreversely burnt so I hope to find a solution here.
Thank you

Selling the following. All units are new. $20 flat rate shipping:

-1 Pair of Seas CA26RFX 10" 8ohm Woofer Sub Woofer Speaker Drivers: $260

hello,

for a good old amp with heavy transformer, will a D curve breaker be a good choice ?

Hi Folks.
Looking for a replacement volume control knob for this amp.

Hello everyone. I would like to clarify some doubts I have about the Threshold SA12E diagram.
In the universal FEB schematic:
-Where is the cathode of the diode in U1 (CNY17-3) connected?
-Are the thermistors NTC or PTC?
-Which of the three thermistors is connected to the heatsink?
-In transistors Q14-Q15: Where are their collectors connected?
-Where are the emitters of transistors Q1-Q2 (-7V, +7V REG OUTs) connected?
Thanks in advance to all those knowledgeable in the matter willing to help. Blessings.

Hi! I need help! Download according to manual. What registers need to be configured for the chip to reproduce sound?
I can’t answer in the profile topic.

I keep reading that Open Baffle is the dogs bollocks these days for sound quality. And a key reason is lack of box colourations. And especially the bass - afterall, many OBs use monopole tweeters. However, despite the wealth of objective data for speaker performance I've not found a link to information on box colourations. I'm wondering if it's become one of those concerns that people re-quote because they read it somewhere else. Is the benefit of OB really a lack of box-colourations or is it really all about dipole vs monopole and nothing to do with the box. How bad is box colouration when a box is built with care - good design and appropriate materials. Is the distortion down in the noise. Would anybody really build an OB just to escape from box colouration alone ? Or is it about the time delays of reflex and or TL enclosures, would the use of sealed boxes 'fix' this aversion. Or is it not about the box, but the standing waves that must occur in a BR/TL design even if the box were perfect (no vibrations at all) ?

Just start to get involve in diyAudio, and would like to say Hello

Hello DIY Audio Community,

I’m thrilled to be back on this forum. I’ve been an electronic DIYer since I was eight, focusing on amplifiers, and later on, digital hardware design and software machine coding for industrial automation. Though I’ve been around this site for quite a long time, my accounts have been lost and found (and lost again) over the years. I look forward to contributing and learning from this community.

Best regards, pSymon.

Hey !

I've been a fan of music since my teen years (yeah - that's quite a bit of time ago) and have accumulated quite a bit of audio gear 🙂
After being an early adopter of slimdevices/Logitech squeezeboxes I found that building my own streaming devices was more fun - first with recycled PCs, then mini-ITX boards, and nowadays with low power embedded boards paired with good DACs/soundcards and rotary encoders, oled displays, in self-made metal/wood enclosures, etc.
I've been experimenting with camilladsp, room correction, etc for a while now - still using LMS to stream my collection of albums around the house.
I used to think of myself as an audiophile but this term has become pretty "loaded" - So let's say I simply like good sound; as a down-to-earth EE I appreciate fine gear but I can't stand vastly overpriced 90% marketing snake-oil *phile stuff (hopefully I won't get too much flack for saying this lol!). Good sound is good enough!

Cheers!

I was studying more about subwoofers and looking at the marketplace I noticed that 8-inch subwoofers are always recommended in very low volume boxes (around 16 liters).
From what little I have studied and seen here on the forum this seems to be quite wrong, for a subwoofer to reach lower frequencies we need a reasonably large box and 16 liters is something very small...
For a 3-way project, which is what I'm studying most in the future, 16 liters would be too small to store 3 speakers (4", 8" and a tweeter).
When I got the specifications of the 8" subwoofer and put it in winISD, I put an initial 35 liter capacity at 30hz and it still worked until it was "well", this in a ducted box because reading the article on the Eminence website it said that at least QTS of this woofer, the ideal would be a ducted box...
I would like to know the opinion of the elders here on the forum, what would you do with an 8 inch subwoofer? box litter and such

Hi everyone,

I'm Rasan Samarasinghe, joining you from Colombo, Sri Lanka. I'm excited to share my latest DIY project: a 100W + 100W stereo amplifier. Here are some key features of the amplifier:

• Power Amp: STK4231
• Tone Controller: LM1036
• Virtual Surround Sound: LA2615
• Spectrum Analyzer: LM324 and KA2284

Additionally, this amplifier includes FM, USB input, and Bluetooth connectivity, making it a practical and convenient audio solution.

I've documented the entire building process and would love to share it with you all. Below are some resources for you to check out:

Photo of the finished amplifier:



YouTube video demonstrating the building steps:

Login to view embedded media
Detailed Medium article: Building My DIY Stereo Integrated Amplifier: A Step-by-Step Journey

I'm looking forward to your thoughts, feedback, and any suggestions you might have. Let's discuss and share our DIY experiences!

Best regards,
Rasan

Hello all, finally finished up the speakers I've been eager to share. They are a three way speaker utilizing all Dayton audio drivers. The woofer is a an SD315, Sig 180 on mid, and the ND25FW for the tweeter. I find these drivers offer excellent performance and allow for easy integration. At the time of writing the total cost in drivers is about $300+ tax. I feel this is an excellent value for a speaker that offers such response and dynamics. I find myself thoroughly enjoying their representation and I have no complaints with them which is pretty rare for me, If I could change one thing, and this may come to be a change I revert, is the tweeter could be wider. I have a few I can try out to see.

The total cost of these is well, I'd rather not know at this point 😉 The are finished in cherry veneer and clear shellac, I put a lot of time and effort into the finish and I'm very happy with the result. One must really take their time if they want to get things perfect. I wasn't able to get that, in the form of poor pattern matching but the veneer was expensive and I was already cutting it short with an 8x10 sheet. I've heard cherry will darken over time so I'm pretty excited for that. I wanted these to be something I could live for for a long time.

They are currently being run active via EQ APO and the results sound great and appear to be so in the data as well. I will eventually have to muster the curage to move them outside and try to get some good measurements on them. I tried a Dayton DSP408 and was sad to find it didn't satisfy my noise requitements, would've had been neat to add even more Dayton stuff to show it's value but I think $160 is just a little too much to ask for such a device in my setting. I'm eager to develop passive filtering for the speakres for ease of use and to being the noise down, and because I see it as a necessary knowledge set for me knock out. The current filters are implimented via onboard motherboard sound, and my computer thinks its surround sound, so movies have no dialogue (open to a fix for that if anyone knows of one, can't video player that will force stereo playback).









Just 2nd order at 300,2500 and a few filters for the mid bass and low end to knock down some room issues.

Hi,
I'm Gaël, from France. I'm a beginner guitarist and to work, I like to use OpenUnmix to split the tracks of the songs I work on. I do that usually with a simple bash script. I talked about it to my guitar teacher and he is very interested. But he is not a geek at all, so I started to think about a solution for him. I have built a GUI around OpenUnmix to easily extract tracks from YouTube videos. It works well on Linux when installed with pip (pip install yaas), but the installer I built using github actions (https://github.com/kleag/yaas/releases/download/0.1.26/yaas_installer.exe) does not work. I have no experience with Windows and don't have easily access to a Windows computer. So, I'm searching for help to finish the packaging. I suppose that it does not miss a lot of things, but I cannot find easily what.

If there is Windows and python and github actions people here, I would be very happy to receive advice or even PRs to https://github.com/kleag/yaas

Best,

Gaël

Ive been looking online and unlike with many car clubs/forums, there is loads of how to guides, posts and threads showing people how to do different mods and repairs or upgrades in parts.
There seems to be very little or next to nothing online, Ive been searching for stuff on some specific amps, but also just some stuff on basic theory and guides to modding amps.
Unless there is some specific trick to getting accurate search result on here, i dont see very much if anything on here.

Which is a surprise for a website called DIY Audio?

Has anyone found some usefull stuff/sites online already?
Is there a way to get better search results on here? or are there already guides/ how to's on here?

Does someone know were can i find this lamps ? those are Rlamp-16v for Lp1-Lp5 in the service manual, that is incandescent lamps for the display of a cyrus tuner

Hi

looking to find a good regulator I am using LM350 from many time
On specs it seems to have a very good ripple rejection, typical 86 dB



Do you think is true?
Something better?

I like it for different use

Bye

Walter

tpa 3116 vs STK 4231

Both are 100w
My usage is for aiwa bookshelf speakers

Hello everyone, I'm seeking suggestions for 'precision' current source/sink and RPS designs suitable for the Akai AM-2650 amplifier. More importantly, I would appreciate your input on whether such a mod/addition would be (audibly) advantageous for this machine. The schematics have been redrawn (with minor glitches) and are quite clear. I've already upgraded/matched the drivers to the MJE series and replaced the power output ones (and recapped it, of course). Thank you in advance for your insights!

here's the link from akdatabase: (also like to extend my gratitude to the individual who meticulously redrew the schematics!)

https://akdatabase.org/AKview/albums/userpics/10007/Akai AM-2650 Schematic.pdf

I have a brand new FAST TL finished in satin black lacquer for sale. It’s hand crafted by a master cabinet maker out of all 3/4in Baltic birch plywood. Beautifully finished in a dozen coats of hand-rubbed lacquer for a satin black tinted finish. Perfectly tuned and balanced. The TL damping was hand tuned using DATS impedance measurement for optimal bass response and low group delay. Premium crossover components on custom PCB. If you want to hear what this speaker is all about, and many people have built it, you can buy one ready to run (RTR).

It is in my shop and list price is $2995 and will ship anywhere in CONUS for $425 via FedEx.
More technical info here:
https://www.diyaudio.com/community/threads/10f-8424-rs225-8-fast-waw-ref-monitor.273524/






This speaker is 83.2dB at 2.83v and 1m sensitivity after baffle step. A true 8ohm load and never dips below 7ohms. One of the top 3 speakers I have ever heard anywhere. You will love the sound.

Hello.

This is my first post, I found this forum by searching the internet for a solution.

I own a Rega Dac the original version released in "far" 2011, on which the left channel recently stopped working.

diyAudio is my last hope to find and repair the damage, before decommissioning it which I don't want since I am emotionally attached to this particular device.

I'm looking to find its schematic or service manual. Please, if someone has it, share it with me, even at my expense.

Thanks.

So I've been curious about Atmos but I have no interest in getting a dedicated AVR. So far the options I've seen are:

1. PC software decoding with the Dolby Reference player. This can be combined with several options, such as combining USB sound cards with ASIO4ALL (apparently), or for example, outputting DANTE (virtual soundcard) to processors like A&H AHM-16 (or DANTE-enabled amplifiers, whatever). This will work, but only for files that have been ripped from BD. Streaming won't work with this solution.
2. Hardware decoding through a dedicated DSP board. Analog Devices seems to sell a board based on ADSP-21573, the ADSP-SC573-EZ-KIT, which has 12 line-level analag output and HDMI input (which apparently can be extended with a daughter board to 24 channels, but "need an HDCP license for this").

But my question is, does this ADSP-SC573-EZ-KIT board provide the required firmware to decode atmos? Is a license of some sort required? The manual for the board makes no metion of Atmos or Dolby at all. Also, the other thing that I'm confused about is the extra channels and the HDCP license. Won't Netflix on PC, or a BD player refuse to play if the device isn't HDCP compliant?

Hi everyone!

I'm Rasan Samarasinghe, tuning in from Colombo, Sri Lanka. I joined this forum a few months back but didn't get around to posting an introduction until now. Professionally, I'm a project manager with a background in software engineering, and I'm passionate about DIY audio and electronics.

I've been into DIY projects for a while, and now I'm diving deeper into audio gear, especially amplifiers and speaker systems. I'm here to learn, share ideas, and get inspired by all the incredible projects you all are working on. Looking forward to connecting and chatting with fellow audio enthusiasts!

Cheers,
Rasan

Hi everyone, I would like to ask for help. I have a Marshall 9200 amplifier with 5881/6L6WGC. I managed to adjust the PI tubes with the oscilloscope, but the thing I really can't do is the bias, unfortunately I noticed that various methods are mentioned on the internet, they talk about shunt method, switch, 1 ohm resistor in series to pin 3, resistor between Pin8 and ground and a thousand other methods, some a 10 ohm resistor, some 100ohm. that it is not known what they are used for and there is no real explanation for each method applied. Up to now I have only accumulated a lot of confusion, I would like to be able to adjust the bias and I know that this amplifier has a trim pot that regulates all 4 finals together, but at the same time be able to move from one final valve to the other with the multimeter. another to see how much difference there is. Since I have other 5881 tubes I might try to match them as much as possible. Up to now I have tried with 4 sockets with a T3 amptata box which intercepted pin 8 of the cathode and measured directly in mA but gave anomalous measurements on both heads such as 52mA at the minimum negative end of the trimmer. Second method tested, soldering 1 ohm 1 w 1% resistors in series to pin 3 of each valve, I connected the multimeter in mV in parallel to the ends of the resistor and I measured 3.4mV but the most absurd thing is that if I keep the leads on the ends of the resistor in parallel and I select the reading in mA in the multimeter in the order of the units I get 0.034mA which could be plausible but the strange thing is that that figure should be in mV not in mA if I'm not mistaken. I would like to understand whoever had this amplifier and what method he used to adjust the bias. Thank you

i am trying to get a leevers rich e 200 running properly - needless to say i have about 4 amp boards only one of which works [ board c11735/1] and 4 others which i suspect also ought to work [50p - serial 4011] the main differences being minimaly the front end and discrete component amps - any one with any specific knowledge and preferably a schematic would be greatly appreciated - don't attempt to mail me the schematic as my web site is too small to accept large files
also - any schematics relating to the headphone line and buffer amps greatly appreciated
also
my friend cliff is attempting to build a 16 track telefunken m15 and has most of this in place - he has had some difficulties with the bias oscillator getting the second oscillator active and would like to have a schematic for this and the counter board - the numbers of these are
bias - 25.5069.251.00
counter - 25.5069.015.00
regards mikeb

Something I can't explain. A basic source follower in LTspice. When I put 10V at the gate, I expect something like 6-8V at the source, depending on the type of MOSFET.
Yet I see no Vs to speak off; tried several models from LTspice, same thing.
I feel I make a basic mistake here but have no idea.
Help?

Jan

Here is for sale my Plinius CD101 CD player. I'm not the first owner but have had it almost 2 years. It works perfectly. Condition as near mint as possible.
Included is the original remote control. The player is heavy, so is the remote.
Original sales price was around 5000€. I'm selling this for 500€. Good deal for someone who wants to match to other Plinius components or just looking for not so ordinary player.
I have moved completely to streaming solutions. Already got rid of almost all the CDs.

I can ship to almost anywhere, but I don't have original package. I'm confident I can still ship it safely.

-Sami

Here is a link to a video of the player in action:
https://photos.app.goo.gl/Jp7W3Y3tQvrPws746

Hello,

My latest preamp/switcher project and build. This pre offers all the normal functions you'd expect in a pre, along with a couple selectable features. The design and layout of the board was done by fellow DIY'er, jhofland. It is based on the excellent OPA1656 chip, and other support ICs along with a few TH parts, and external breakout boards for volume, selector and headphone. The PCB is double sided and turned out beautifully. It has a fully, self-contained and integrated PSU. No power brick required.

This project had it's roots in my desire to have a matching preamp, to mate with a recently completed Modulus- 86 amp build.

Latest Preamp and Modulus-86 amp.


As mentioned before, the guts of the pre is a double-sided preamp PCB. The design specs feature;

o - Based on TI's OAP1656 opamp chip.
o - Uses TI's OAP1637 fully differential chip.
o - Uses Analog Devices' MAX79220 headphone amplifier.
o - 1 balanced input
o - 3 single ended inputs
o - 1 balanced output
o - 1 singled ended output
o - 1 separate headphone amp
o - 1 subwoofer output w/selectable crossover at, 80, 120, or 200Hz
o - 1 12V Trigger out jack (3.5mm)
o - adjustable gain at 0dB, 6dB, or 12dB (onboard 4-pin DIP)

Other features include;

o - Use of small breakout boards for the;
(1) the volume control pot
(2) the input selector with LED KK connectors
(3) Headphone output jack
Micro-match connectors are used for connection from the main board to the above remote breakout PCBs.
o - All I/O is also available with the use of MolexKK 2 and 3 pin PCB headers.
o - All onboard and integrated PSUs. No power brick to contend with.
o - Integrated IEC connector on read panel.

Top/Bottom view of the PCBs;


Here is what the fully populated board looks like, sans the 5V power module.


The objective of this particular project was to build a general purpose preamp with the features I wanted, and more specifically be a matching 'mate' to my Modulus-86 amp. This, of course, would involve using an identical mini-ITX as pictured above. I like to experiment with new and different enclosures that aren't run of the mill silver and black traditional audio cases. Because of this factor, you're never sure if you'll be successful in getting everything installed in the same sized case. Hence the custom preamp PCB. The PCB is 140mm x 140mm. This doesn't leave any room leftover for other pieces you may need. I had a pretty good idea of what I was dealing with and other remote software module I was planning on using in the build. The PCB turned out great as fabbed by JLCPCB, and fits perfectly in my red case. This mini-ITX HTPC is available online here at Amazon.

Using this type of unconventional enclosure general will require more than just drilling holes. There is a degree of case work that's required in the way of front and/or back panels. I have a 3D printer that works well for creating custom sized panels needed for converting a computer case to a useful piece of audio gear. And, you have to be prepared to modify your design as you go along. 🙂 This is a very challenging and time consuming process. And if you're a perfectionist well.....you know how it goes.

When considering the features I wanted in the preamp, I wanted to make it as flexible as possible, so that it could be used in various types of situations and enclosures. One of those features is the use of either; (1) RCA jacks that can be soldered directly onto the PCB, or (2) use 3-pin MolexKK headers on the PCB. The former would involve easier case work, as you could simply cut out a rectangle on the back panel and expose all of the pre's I/O more easily, while the latter could be used with casework that already has holes for the I/O. These are simple alternatives depending upon your preference and implementation. This feature is not available for the balanced connectors.

Here's an image of the various I/O connectors and footprint for the RCA jacks.


Another feature I like to have, and is on all late model PC cases - for about the past 20yrs - is the momentary on/off switch on the front or top of cases. To take advantage of such a switch you need some sort of low-voltage switch to trigger the mains, or simply act as an inline switch to a PSU. In past projects, I've used a small softstart switch (also designed by jhofland), that is ideal for a MO switch to turn on new builds. It provides for using a single switch, and even the Power and HDD LEDs also on the front panel of mini-ITX cases. I use these in almost all my projects over the past couple of years.

Remote low-voltage softswitch.


Also designed into this preamp are the breakout boards for the 3 operational features like; (1) Input selector, (2) volume control, and (3) headphone jack. Putting them on breakout PCBs allow for different mounting/placement options. The Micromatch (TE Connectivity) connectors and cables are used to connect them to the main preamp board.



Here are a few images of my build in process.

Final layout of the Back Panel. (4MM thick 3D printed)


Fully wired up preamp.


Fully finished and closed up preamp with smoked glass top.


The dynamic duo. 🙂

Temporary living room testing setup with vintage, HP-100 4-way speakers. The combo sounds so awesome, and the dynamics are really something you've got to hear.

If interested in the PCB board for this preamp and/or the low-voltage softstart board PM me for details.

Enjoy,

Rick

Just wondering if it's better to go all A2, or some class A + A2 ?

There has been some discussion in the past on getting B&K or other high quality metal diaphragm mic cartridges to work with non-proprietary audio interfaces. Generally, these systems have odd connectors, require odd power supply voltages. and would require significant DIYing to work with standard USB audio interfaces. While digging around online I discovered the NTI M2010 microphone has a very nice ACO Pacific 7052 metal cartridge, and also has a standard 48V phantom power XLR input. The retail price is $1395, but there happens to be a surplus place in Canada selling a mountain of them for ~$255 ea. on fleabay at current exchange rates.

I called NTI and the rep told me the mic will work with a standard audio interface. He also said they can provide the original factory calibration data by email on request. He said that data should still be valid after many years, assuming the mic hasn't been "knocked around." Alternatively the mic could be calibrated at CSL ($60) or Scantek ($175).

This seems to me like an attractive option for a measurement microphone. Even with precision calibration from Scantek the cost of a used mic in competitive with mics like the Earthworks M23 or iSemcon. Thoughts?

I had a notion to use the bass guitar case itself as a “box” to mount the speaker portion of a bass guitar amplifier, and have it serve dual purposes.

For reference, this theoretical bass case would run 48”x16”x4-6” ish in size, and be made of chipboard or thin plywood. At least normally, it’s being designed and built to purpose so can be thicker, etc. the speaker can top mount, or bumped out some.

At first I was just thinking of mounting a shallow woofer or mid-bass speaker somewhere in one of the unused “cavities” created by putting a very non-square electric bass in a very square box, lol.

Then I ran into the whole flat panel speaker/exciter thing and started thinking…… what if the whole case was the speaker?

Bass guitars start in the 30hz range but while it’s nice for those frequencies to be there for some fun-thump, most of the real work happens maybe 150hz to 4k. I may still try to squeeze in some kind of sub, to fill the bottom end out. Usually most combo amps are using full range or mid-bass drivers, so they also roll off the low-lows too.

Might it really be as simple throwing in an amp and securing exciters on the inside of the box? I guess it’s cheap enough to try.

Would moderately stiff panels like that still radiate anything? I could also anchor the exciters to the case and use a “floating panel” of balsa or thin ply, then add external protection of some kind?

I’m excited (-😉 to give it a whirl. I figure I’d ask anyone with experience if I just totally am barking up the wrong tree?

Hey all - excited to learn a bit more from this community.

Currently a massive DIY car audio guy with a pretty competitive nationally ranked vehicle filled with Accuton Automotive, Focal Utopia, Brax, Mosconi and other nice SQ brands. Love the DIY side.

My truck's front stage:


Amp rack I built:


On to the home audio side:

Been looking to create myself a basic, but quality reference 2.0 or 2.1/2 system at home. 1 - I get to enjoy music in a much better environment than in a car
Probably a bit against the DIY grain but I have a set of KEF Meta R3s on the way and a WiiM Ultra pre-ordered as my streaming/DAC/pre-amp. Still in the discovery stages of what I am trying to find for an amp and long term a sub.

Excited to read more here.