Hello,

i am Hannes from the little town Mooskirchen in Austria.
After a long time reading here about very interesting stuff was the logical next step get activ in this forum.

To hear music was everyday my greatest hobby and with the buying of a own house the chance where in eyesight to install bigger speakers 😍
I like to build my speakers and electronics by myself.

Greets Hannes

Hi All
I don't know if I am late to the ballgame but I just found a free software for plywood layouts. You just tell it the size of you material , the panels you need, the width of your blade and it lays them out including grain orientation and many other features.
I have absolutely no affiliation with this product.

Just search Maxcut, There is a nice youtube to show how to use it.
Jeremy

Hi,

I am looking for someone that corrects or redesign a simple pcb from an schematic.

Basically, the board is a kind of breakout board for a TDA1541 dac. This board is installed in the TDA1541 socket and:

1. Routes the TDA I2S input signal to a XH connector. I have placed an isolator to avoid any unwanted ground loop. This isolator is powered with a dedicated psu (independent secondary) and a dc-dc isolator to power both sides.
2. Provides three UFL connectors to connect an I2S signal into the TDA1541 which is installed in the board.

Using this board I can install a FIFO in any TDA1541 DAC without modifying or removing any component. I have build a prototype and it works as expected so I would like to build it seriously but do not the skills to do so.

I have an EASYEDA project I can share.

best regards,
jm

Sale 1 Odroid C2 50 Euro. and 1 Odroid C1 40 Euro.,Good condition, use 1 year in audio file server.

Hi,
I've encountered a problem with my Neutrik A1.
The output of the amplifier is working only on the (2) +pin of the XLR and the (3) -pin is presenting a very low voltage square-ish wave.
As a consequence of this, all the measurements are 6dB lower than expected.
I looked everywhere but couldn't find a service manual or schematics.
Is anyone able to provide any help?
Thanks in advance!!
Michele

Looking to find a nanodigi 2x8 so I can try out activecrossovers. Not really interested in a 2x4HD and can’t justify the price of a FLEX until I’m sold on the tech.

Dear Fellows Audio Enthusiasts!

There were several reports that our VCX MUSES volume control boards exhibited spontaneous volume jumps to 99 or a 100.
Upon thorough investigation, we found that those jumps were caused by some silicon issues, and developed a workaround that eliminates the problem. It was a lengthy process and we greatly appreciate the contribution of the DIY community members to that work.
Please note that VCX units shipped after July 15 2023 are free from that defect.

Please note that not all the VCX boards shipped before July 15 2023 were affected by that problem. Nevertheless, we take seriously the quality issues, and we sent personal emails to each and every customer, who purchased the VCX that may be affected by the volume jumps problem and offered them to return the boards for a free firmware update. As a token of appreciation of those customers loyalty and patience with each reprogrammed VCX unit we provide a unique discount code to purchase our products.

If for any reason you missed your RMA letter in the mail, feel free to contact the company for the free firmware update.

Thanks again for your continuing support!

Lenny Novikov
Academy Audio Inc.

Hello!

I'm on a quest to build an active sealed 3-way using the sb acoustics ceramic line of speakers (5 inch mid and 8 inch woofer) and just today placed an order for the 5 inch augerpro waveguide for the sb26cdc.

I had the crazy idea of using a plastic draining tube made for placement in the ground as an enclosure for the mid? This would make the build much easier since I am aiming for a more compact design to be used as studio monitors primarily.

I have tried researching the topic and it seems like it might be ok?

Here is a link to the swedish website of the tubing in question https://www.hornbach.se/p/markror-pipelife-pp-sn8-o200-x-1000-mm/10601365/

It says polypropen which i guess is polypropylene in english?

So what say you? Does it work or is it ill-advised? my thought was a tube running the entire length front to back and then stuffed, maybe gluing a bunch of bitumen pads around it in an effort to damp it?

I'm looking for 4 ea, ESL-63 mid/treble panels.
Defect no problem, will consider buying complete steakers if price is right.
Preferable EU or continental Europe.

Jan

Dear Sirs,

I bought from eBay a functional Rane RPM26z processor, except it's password protected when I try to access it by it's control app DragNet. I tough that's not a problem, just have to reset it, remove a button battery or rewrite the FW, but seems it's not that simple. What I found:

"For maximum security all passwords are stored in a protected area of non-volatile memory within the RPM device itself. Updating firmware does NOT erase these passwords or disable security in any way. Please keep track of all passwords. If a password is forgotten or lost you must contact Rane tech support for information on restoring the password and gaining access to the device. There may be a charge for this service."

I sent message to Rane Commercial about the problem --they were taken by InMusicBrands in 2016-- and they replied:

"...unfortunately this item was discountinued long before we took over Rane and sadly any available documentation we have does not mention any passwords for this device sadly. This process must have been something that the previous support team provided however we are unable to confirm for sure.".

I've got refunded by the seller (obviously he doesn't know the password) but now I am standing in front of --otherwise-- a nice processor and thinking how to break in. The thing should support brute force password attack, has no unsuccessful tries limit or timeout and I want to know if anybody have any better idea what to do? Many thanks in advance for any suggestion.

Regards,
Dorin

Hi there dear members!
I have bought me a Krell KST 100 amp and im curious if there is anyone out there with the information about the voltage settings on this one??
I do have the exploded view of the amp but there is nothing that tells me how the voltage is changed. I would be grateful to get some help on this one!!

Tested 102/102, 102/101 on a tv7. These have the three rivets on the plate. Comes in original tethered Sperry boxes dated 9/52. 70.00 plus shipping and paypal fees if used. I prefer friends and family or personal check. I sold a pair on ebay yesterday and they charged 14.00 to sell a pair of these for 80.00. Getting older and tired of making other people rich.
Thanks OLD BIG

Hi all,

i am using some old second hand drivers to try and make a car speaker system. I have a 10" central driver with two 4" mids and two tweeters. i am unsure on how to decided on an amplifier circuit to go for, is it worth splashing out on an expensive one or are the cheaper ones with less inputs still going to work.? i also wondered if anyone had any suggestions on how to build a crossover circuit or will it be significantly easier to buy some?

Cheers

I have available a small quantity of PCBs and Front panels for building the accelerometer preamplifier as described in my article in Audioxpress June 2011. You can find the article online if you have missed it (Test Your Speakers? Performance with this DIY Measurement System | audioXpress).
If you are interested, send me an email: gntanavaras@gmail.com

Hi folks,

The title is my question.
Small batch (up to 10 sets) is preferred.
As pretty flexible with design, core power size can be any from 40VA to 200VA
Any help?

Hi dear diyAudio community,

I use a Dayton DAEX32EP-4 exciter with a XY-502 Digital Power Amplifier and a powersupply with 24V and 1.4A. At the beginning everything worked out fine, but after using it for an hour or so the exciter started clicking. I also tried other exciters and the same happend. Does someone of you know what the problem could be? I have uploaded two videos to my drive which you can find here.

Thank you very much.

Best,
SonicDriver

I want to build my first diy speakers using a 2 way design and simple second order crossover. Why 2 way little speakers?
My listening room is not huge, so don't need really big ones.
I can't use loud bass because disturbing/shaking next door people. Finally also the "wife" don't want monster speakers and my listening preferences are not related to big-boomy bass at all.
I'm also starting the path to build a Master's Nelson Pass clone (the old Aleph 3+27), so not huge power, only pure 30 watts in class A (if God bless me letting me finalizing everything).

I'm sharing my first newbie insights and thoughts before proceed with the purchase of speaker components. I'm sure I can get some advice from seasoned speaker builders, advice on things I'm not aware.

My budget is limited, so my first decision was to use Wavecor drivers, cost contained but seems to be good ones, easily found in the European diy market and widely used as OEM speaker parts. The web page is also full of information.

First step.
In order to get some insights and inspiration I looked into different existent speaker kits using Wavecor drivers, having full information on the web, for example:

Wavemon 182, ported, using tweetter TW030WA09 + Mid-woofer WF182BD03
WaveMon 182
(I runned a simulation for this one too)

Loire Top, sealed, using tweetter TW030WA10 + Mid woofer WF182BD12
Loire Top

CSS Criton 1TD, ported, using tweeter TW022WA04 + Mid-woofer WF182BD10
SHOP | css-audio

Later I found a freeware Loudspeaker Simulator named VituixCAD by a genius guy named Kimmo Sauristo, and also found all the datasheets and full specs for simulation in the Wavecor page:
Database

After revising these above and other diy projects, and having all this in my mind, I selected the drivers with which I would like to bulild the speakers:

The Wavecor tweeter TW030WA11 and the midwoofer WF182BD10
TW030WA11_12
http://www.wavecor.com/html/wf182bd09_10_11_12.html

Found the midwoofer having interesting specs (low Fs and good overall characteristics) and being highly appreciated by many builders/listeners.
The tweeter was selected because the specs seems to be very fine compared to other Wavecor items. Selection was most a matter of intuition than deep knowledge.

As said, with full specs in hand (as found in the Wavecor web page), and after calculating a first voltage divider for the tweeter and selecting first filter values running on-line calculators, then I began to make many adjustments (playing up and down with capacitor, resistor and inductance values) with VituixCAD (was a very interesting experience with this marvelous tool) and got final setup..
The results are in the photos attached to this thread.

One photo shows the very simple crossover and component values, other the SPL simulation result with tweeter inverted phase/polarity and finally the filter graph showing a cross point at approx. 1898 Hz (this is not a problem for the tweeter, having a very low Fs of 410 Hz).

My question to any seasoned speaker diyer:
To me (a newbie) the results as per the photos seems to be fine. They reflect the drivers frequency and impedance bahavior. Is this trustable or I'm missing something?

Then.
My plan is to build a ported enclosure (not yet decided) between 15 and 17 liters, Fb between 37-39 Hz and F3 between 40-42 Hz. I know this will modify the SPL frequency response, but only in the lower first octave. I guess the results of the freq. response in the medium-upper register will not be affected.

Any thougts or advise?
I'm on a good road?

Looking for another pair of Scanspeak 10F/8414, ideally in the UK.
Cheers, Rob

I’m new here and joined due to a specific problem I am facing. I have an old out of warranty Tom Evans Design Microgroove.

It has too much (factory set) gain for the Rega Ania cartridge (0.35mV) that I intend to use with it.

Please see pictures of the unit inside. As I live in Denmark (EU) it will be very expensive and impractical to ship it to the factory for modification. Can any of you provide some brief instructions and/or a schematic of how to change the gain and any components needed? I completely understand that any changes carried out on the unit are done at my discretion and solely my risk.

Any input would be highly appreciated!

The most famous is probably the Eckhorn from Klipsch:
https://www.klipsch.com/founder
https://www.pinterest.de/pin/626352260655991272/
https://www.arkansasonline.com/photos/galleries/2019/nov/01/gallery-01-11-2019-16-41-59/
https://www.itishifi.com/hifi/klipsch-new-model-t
https://mysoundbook.eu/klipsch-klipschhorn-der-legendaere-hornlautsprecher-aus-den-40ern/
https://www.lowbeats.de/alles-nur-kein-********-der-markante-us-hersteller-klipsch-wird-75/
URL corrupted - keywords for Google (for getting this URL and information there): lowbeats der markante us hersteller klipsch wird 75

I am looking for the first released reviews from 40s and 50s.
Thank you for posting.
Any advertisements from those days in the attachment.

P.S.: this thread don't provide the wanted information:
https://www.diyaudio.com/community/threads/vintage-speakers-the-look.345351/

Hello, If I use a 500ohm resistor instead of a choke 120ohm/20H.

My voltage will get lower than if I used the choke, and I will get more ripple. It will also get even lower when the amp is under "heavy load" (!?sag) with the R than with the L. Ok.

But will I get more ripple when the amp sag (under LOAD) ? or just a lower voltage but with the same ripple than idle ?

Thank you.

Hi,
I have an issue with a Yamaha WXC-50 streaming client / preamplifier. It suddenly stopped providing output via line or toslink output while listening but was still controllable via MusicCast APP. After a few power cycles it finally stopped starting at all, red status LED is blinking 6 times. I checked the Yamaha service manual on hifiengine. The device has a self diagnostic function via browser interface but since it is no longer starting up I cannot use it. I tried the 3 "magic" key combination I am aware of to fix the issue:

1. Restarting the unit: Press power button for 15 seconds
2. Reset to factory settings: Press power button to turn unit into standby, press "connect" and "input" button at the same time for 5 seconds.
3. Firmware Update: Disconnect power cable, connect USB storage, press "connect" while connecting power cable.

Unfortunately, none of it fixed the issue, firmware update seemed to have worked but after the update the same error occured.

According to manual blinking red status LEDs means:

• 2-8 times blinking: As a safety precaution, the unit has turned itself off.
• 4-8 times blinking: As a safety precaution, capability to turn on the unit is disabled. Contact your nearest authorized Yamaha dealer or service center to request repair.

I could verify that +15V and +5V voltage is correct, I guess the others voltages are only available if the device is fully started.

Does anyone had a similar problem and was able to fix it? Are there any other "magic" combinations e.g. to enforce a startup of the device (in order to be able to use the self diagnostic function)? Do the blinking times encode specific error conditions?

Best regards
Randolf

Hi forum members. I was looking for some advice on a recent equipment change.
My existing pre-amplifier failed and I set about replacing it on a tight budget. I bought a Cambridge Audio C500 for a very cheap price even though it was sold as "not tested".
So I set it up into my Arcam P85 power amp and listened to some music. Guess what!, everything worked fine, it was in great condition and it sounded superb.
I was congratulating myself on a bargain but when I shut the Pre-amp down there was a small pop from the speakers and my power amp decided to shut down.
It did this a few times but there was no damage to speakers or power amp.
So my question is, is it safe to carry on using this provided I switch off the power amp before the pre amp?
Also does this fault ring a bell with anyone? I have had a look inside and it is pristine. I cannot see any bad caps etc.
Many thanks for your thoughts.

I made this last year but never used it,I have plan to use this in some A class amp.Plese look on picture.price for all 4 boards 60 euro plus shipping.

This is a I2S to simultaneous mode TDA1541 dac board designed by Miro.

Your own PSU, i2s source and two single op amps (i am not supplying the op amp) or your own IV stage is required to complete this DAC for it to sing.

The 14 decoupling caps for the TDA1541 chip are high quality RIFA MKP, with values as per Miro's recommended BOM. Decoupling caps for the psu are KEMET MKP, and electrolytics are mainly Nichicon FG for the DAC section and ELNA Cerafine for the op amp IV. Resistors used are good low noise, metal films from Nikohm, vishal and Dale. Logic chips are decoupled with high quality Kemet SMD x7r capacitors.

A blank DC protection board is also included in this sale. You will need to get your own components to populate the board if you intend to use this.

This dac is designed by Miro and more info can be found here :
https://www.diyaudio.com/community/...s-input-nos-r-2r.354078/page-268#post-7159210

Miro also designed the PSU for this dac (not included in this sale):
https://www.diyaudio.com/community/...s-input-nos-r-2r.354078/page-268#post-7159234
Please study the power supply requirement carefully if you intend to use your own psu design.

Important things to note :
1. If you intend to have no capacitor at the output, it is advisable to have a dc protection board (blank board is included in this sale) as explained in the post:
https://www.diyaudio.com/community/...s-input-nos-r-2r.354078/page-285#post-7187720
2. i have trimmed the TDA1541 offsets to be null and very stable. Any changes to the board, including inserting different op amp and different TDA1541 chip will require adjustments again. Please do check and do necessary adjustments by following the instructions by Miro. You will need to explore this on your own, with your i2s source connected.
3. All components, including the TDA1541A chip are new, which is only used for the testing of this DAC.

This kit is for sale at US$200 (Shipping with tracking is covered). Paypal FF only please. I am a responsible seller and I pack my item very securely and ship fast.

My dac comes with an external 15V small and cheap wall wart psu. A friend of mine measured it and it produces a lot of noise... not hifi at all as expected.

I'd like to replace it with a more serious linear psu. The Dac has onboard regulators for all voltage lines (12, 5, 3, etc) including the analog section.

What is the best approach:

A) a simple linear psu giving 15vdc that uses just rectifiers and smoothing caps

B) a regulated psu using something like LM317, or LT1086, or even with dual regulators

I'm pretty sure that A) should be better than the cheap wall wart, but not so sure about the apparently better option B) is really problem-free. I remember that once I read somewhere (I can't locate the source unfortunately) that putting in series psu regulated with 3-terminal regs can create more than one problem.

I hope somebody can help!

I decided to add a Pre OUT Power Amp IN loop to my Code 25.

Although I quite like the sounds of the Code 25 I found it extremely glassy and has too much biting high mids for me. So I wanted to add an EQ.

I find the inbuilt EQ pretty poor, and the fact that you have to save each eq setting in each preset, well I found that was a pain in the …

I just wanted a standard -on the fly- tone control I could adjust.



So if you want to do this mod I should firstly say:




DONT DO IT

1. It is dangerous with mains voltage in there.
   
2. You could break the Amp.
   
3. You will have no warranty as soon as you open the back case.
   

So the Amp seems to have fairly standard Preamp out – Power Amp In type arrangement.

The only odd thing, is that there are 2 x signal cables from the Preamp to the Power Amp in.

It is a 4 pin connector on the Pre and on the Power Amp.

It seems like it is a stereo feed from the Pre amp.

I guess that's just for the Aux in from a phone or similar, and it continues this signal on to the Power Amp board where it directs it to the stereo Headhone Jack.

But the Power amp it self is mono of course.

So if you just short the L,R together of the signal wires, then you get mono.

That works fine. You just miss out on stereo in the headphones – but that doesn't bother me.

Note the Code25 effects seem to be just mono.



So in the picture shown, you could cut into that signal wire and make the connections there,

OR I just unplugged both ends of the cable and soldered directly to the 2 boards. - Note, its tricky to do it this way unless you are an experienced solderer.



Wire it up as per the image and when you have no jacks plugged in it will work as normal and you will have stereo Aux in sound on the headphones.

And when you plug in the jacks and wire it through the effects loop then everything will be mono.

Everything worked fine on my modification and the level seems to suit a guitar EQ pedal nicely.


Remember as stated earlier – DONT DO THIS 😉

I am in the early planning stage of a modest cost 3-way. I would like some feedback on modest cost ($40 - $60) 8" woofers. The application would be a fairly compact enclosure of 15 - 20 liters, nominal 8 Ohm, sealed box, using DSP to extend the bass response with a Linkwitz Transform... recognizing of course that the bass boost will have to be fairly moderate given the limited Xmax capabitities of woofers in the price range. The crossover from woofer to mid will be in the range of 300 - 500 Hz.

My two leading contenders are (1) Dayton DA215-8 and (2) SBA SB20PFCR30-8

https://www.parts-express.com/pedocs/specs/295-332-dayton-audio-da215-8-specifications-46942.pdf

https://www.madisoundspeakerstore.c...sb20pfcr30-8-8-paper-cone-woofer-8-ohm-round/

I would be interested in anyone's experience with either of these two drivers.

Any other drivers I should be considering? Since this will be a sealed box design, I would like an Fs of less than 36 Hz and a Qts in the range of 0.34 - 0.45

j.

Project- I have upgraded the crossover in a set of Pinnacle Classic Gold Tower Speakers (approx. 2010 ) with 2-8” 6ohm woofers and a 1” 6ohm metal dome tweeter (Vifa). The crossover I built as a 3-way with 150 Hz -1st order to bass woofer, 3200Hz -2nd order between the mid-base woofer and tweeter. This is completed, installed and will not be changing except for the following 'tweek".

Should I filter out the Looking for opinions on pros / cons of adding a 1st order crossover capacitor of 470uF or 330 uF or 200uf to achieve an approx. cross overs point of 60 / 80 / or 100 Hz respectively to the mid-base woofer.

I appreciate your insights, Thanks,

Have a pair of ESL 9205's coming and now wondering about something to run them.
I have only two power amps one a Naim 160 which I'm not sure if it would run them.
The Second was built by someone I know it coped well with a pair of 57's, about 70w
If the worst comes to the worst I can get something else but haven't a fortune to spend at
present also something that is easily available in UK.

Thanks, Ray

I’m fixing a Yamaha CA-800 that had multiple issues. I’m trying to basically make it as good as it can possibly be. I replaced all of the 2SC458, 2SC1345, Sony 2SA706 and Sony 2SC1124 drivers on the amp driver boards. As well as all of the caps. One channel has bad outputs, they are 2SA663 and 2SC793. Sorry for the crappy image, I can’t seem to find a clean scan of the CA-800 circuit.



Here are the basic specs of the original outputs.




I can go with the same package and put in some new MJ21195G and MJ21196G and be done with the easy swap. They exceed in every way and have a close transition frequency of 4 MHz.

The other option would be using some TO3-P packages and using NJW0281G and NJW0302G, just bend the legs and fit them in and they’d be sitting towards the bottom of the heatsink.



Here are the specs of the TO3-P devices.





Again, they pretty much exceed the originals in every single aspect, but have a higher Ft of 30 MHz. How would the 30 MHz do in this circuit. Curious if they’d be any better, even slightly.

Thoughts?

Jupiter Copper Foil Capacitors.

Rated by Humble Homemade Hifi with a very high score of 13.5

2.2uf @ 100V

There are two available

eBay link is below for safe purchase

https://www.ebay.co.uk/itm/26630218...y44TTrC/ybZnlPmW3YoqjJRExG|tkp:Bk9SR6rTrbvPYg

This amp is in protect .There is no short in the output section .When I power it up the first time it played good audio until I bring up the gain.I already tried the jumper from pin 8 to 14 but no luck

Any suggestions

Hi, felt my last build attempt with these drivers didn't have enough baffle step compensation, upper mids were a bit too prominent. Without resorting to filter, what baffle width or enclosure type wd boost the lower mids and bass? TL?

Hey, everybody...

I'm going active on my tweeters for the first time in 30 years (I know... about time!).

I have a small mid-range woofer that's going to play ~700-4000k hz, and I'm going to mount the tweeter adjacent to it (> 4000 hz).

My plan was to mount it RIGHT beside it--basically touching.

What do you think... would that be TOO close?

I also have the option of pulling the tweeter slightly closer to the listening position than the midrange driver. I've seen this in various A-pillar installs, but I didn't know if it was strategic (e.g., trying to avoid diffraction of tweeter frequencies from the adjacent midrange) or simply a function of the A-pillar angling toward the driver.

What do you think... any value in putting the tweeter slightly closer to the listening position?

Thanks in advance for any advice or info you might have!

These current-mirror IV converter modules are from the 2021 GB that Ripster coordinated. I built two boards for my AD1862 MiroDac, The solid core copper wires are still attached to plug into the opamp sockets on the DAC board (original onboard IV components must be removed before these are installed). The other two boards plus "tester" boards are unpopulated. The matched mosfets for set 2 are still labeled and organized as per Ripster. (Who did a wonderful job!)
Also includes the rest of the SMD components needed for assembling the unpopulated boards.

Sold! shipping included within USA only (payment via PayPal)

Hi all... 🙂

With two Aleph J mono brothers coming to life, I was thinking to share my journey with you here. I have collected so much from DiyAudio and never showed anything. These two are my 10th or something-like-that DIY build of amps, preamps and loudspeakers ... but this time I decided to make the chassis first, because I wanted to avoid another neverending "plywood project".

Few months ago started with CAD design and made decision to make wooden enclosures with heatsinks on the back. Heat sinks are generous and will have a lot of free air outside and inside the box for propper cooling and installation of everything necessary...plus some more eventually, that's why monoblocks...



So, after few weekends in my workshop:



Test of VU meters with Variac:



For now boards are populated only with resistors and cleaned so I don't have problems with cleaning when I solder big caps and trimpots and other small stuff...



First installation on the heatsinks - all holes and screws OK, we can continue with assembly process...



Back side, cooling fins will have enough fresh air for good flow:



Never forget Papa and The First Watt... 🙂

For sale The preamp that started my long journey to audiophilia. A wonderful LDR pre created by a long contributor in this forum. I believe the preamp in its DIY version is described in a thread here. I bought the finished product the member has on his website

https://sites.google.com/view/ldrpre/ldr-pre-mkii?authuser=0

He's selling today the new product in ebay (you can see the link in the page linked above) and you can see the prices there. Selling for 450 euros including the matching apple TV remote control. This is a wonderful audio component and I used it probably for about 1 year before I moved to tube based. I still kept it for a future second system project but my current workload is simply not allowing me to get there. PM me for more information. Can ship in the EU. Outside the EU can be discussed if someone really interested. I know quite a few people in Australia bought the preamp at the time.

I have a pair of Foster tweeters from a pair of Zenith Allegro speakers. Mine are the black plastic housing with the silvery domes and square mounting flange.

Does anyone know the SPL of them?

I used them in one of my early speaker builds and used variable l-pads. I'm wanting to go with fixed l-pads instead so there's less I have to worry about adjusting in my stereo.

hi I've bought a rcx1500 to try and fix from ebay. the issue was described as a CD stuck inside this doesn't seem to be the case however opening the unit I find that it uses the icepower 200asc module .
I've noticed a wire dangling suspiciously does anyone have any idea what this might be ? anything else i need to be aware of when trying to fox this is there anyway of checking the capacitors are discharged with them still attached ? bought as a learning exercise but would be nice to get it up and running again thanks

The existing crossover of my speakers, Braun LS200, has 2nd-order topology. I’d like to convert it to 4th-order on woofer-midrange crossovers.

According to car components of the same brand, there are two versions of active crossovers: 642csi and 642ix. The specs are shown below:

642csi
85Hz low-pass @ 2nd-order Butterworth
170Hz hi-pass @ 2nd-order Butterworth

642ix
100Hz low-pass @ 4th-order Linkwitz-Riley
170Hz hi-pass @ 4th-order Linkwitz-Riley

1) I wonder that in order to apply conversion to my LS200 speakers, can I use the ratio of the 642 crossover series? Let’s say the 85Hz divided by 100Hz obtained a factor of 0.85. If, for example, my LS200’s woofers are crossed at 270Hz @ 2nd-order, applying 0.85 factor to 270Hz would yield about 320Hz. The 320Hz be a cut-off frequency of the 4th-order system, shouldn’t it?

2) The original woofer-midrange crossover of the LS200 speakers are 2nd-order and WITHOUT reversing midrange polarity. After converting to 4th-order, does it require to reverse polarity of one driver, either midrange or woofer? Because the 2nd-order and 4th-order system have phase difference about 180 degrees to each other.

All,

I am trying to see how many here would be interested in a 150W plate amplifier using my Starkrimson 150W modules.

They would be 27cm by 17cm. The price will be around $750 per plate amplifier. It will come fully assembled. And includes the following:
1. Filtered IEC connector
2. 275W AC/DC Power Supply
3. Starktrimson Amp Module
4. XLR Connector
5. all needed hardware and wiring

A mockup of what it would like is below.

I have concern that the MOSFETs to the ACA v1.8 may overhead my pcb due to the fact that I soldered them in a way that the MOSFET bodies and the board are touching each other, or will the heat sink dissipate sufficient heat? Should I have allowed for some airspace?

So the little Musical Fidelity A220 got a bit of an upgrade. A perfect way to destress after work, when I have more time I will do some measurements but for now I'm listening through a little pair of CH50s and at the weekend I'll have the Castle Harlechs (1/4 wave) out and have propper listen.

The alternative motive for this is to practice SMT soldering for another project.



That's small (and that's through the 2x lense light.. not as small as the 0402 or the LT4032s that came for a different project..



I thought the soldering was quite simple (the pins also needed soldering.


Aww..



Doh.. poop. the pin thicknesses on the adaptor kit will not fit the A220 DIP14 socket. So with some 600 grit wet/dry sandpaper.. you guessed it.. the pins fit in the old socket 😀

So after the initial power up on some 8R 100W resistors to check it's all ok, it's on to some speakers for a listen. It didn't go bang.. which is good because I note that Mouser have zero stock since I ordered last week! (I triple checked pin1!).

So it takes the A220 about an hour to reach it's equilibrium with the old MC33079P and the new OPA1644A is no different. Once it's reached it's equilibrium. The key seems to be the output devices / VAS stage like being at a certain temperature.

Initial impressions when cold are snatches of more detail but no musicality. However now the amp has warmed up it seems to show detail in complex pieces whilst retaining musicality without seeming being tiring. Phew. It still needs more listening but so far it seems like a keeper.

The A220 got repaired with new caps, new rectifier, and I thought I may make this change back then so used Panasonic hybrid caps to give a 5mOhm ESR preamp power supply. I don't know at this stage if the preamp power changes really makes a difference but the OPA1644A is a pin-compatible replacement (once mounted on the adaptor) that seems to make a decent step in clarity.

When I have some time I will do some tests to compare the two chips.

I have 2 TKD2cp2508-S 50k pot.
Shield in center,A curve
65usd each 30usd shipping from Japan.
5usd shipping with ferry(taking around 2 month)

Hi Guys, Im new to the forum.
I've been working on a custom intercom circuit that I want to build for Paramotoring. I'm using my Bose A20s rather than using a standard Paramotor Helmet and headsets (basically just a bike helmet and modified ear muffs!), the helmet I'm using in my hold crew chief helmet from my army days. Anyway, I need an intercom circuit for those to function correctly. and I also need to be able to switch between two different radios for transmitting but listen to both, I also want to record all the audio of my conversation in the air when I'm by myself for vlogging and also for when I carry a passenger. I bought a Pilot USA PA200T/A24 Mini Intercom, and it works well, but its missing those extra features that I want. My goal is to have a PCB Printed that has everything in one and is compact. Todo that I need to either reverse engineer an existing PCB or start from the ground up with an intercom schematic and add the parts and features I need. I found one diagram that looks to have what I need however, Its kind of blurry and hard to read. I'm unable to message the person directly that posted it as I'm still new and "Under moderation"

Here is the original thread I found the schematic in
https://www.diyaudio.com/community/threads/aircraft-handlers-communication-system.344837/

My Circut needs the following features

• 9V Power Supply
• Two radio connections with selectable PPT, one will be the Yeasu FTA-850, and the other will be my Ham Radio an VX-8DR, my thought is some kind of quick toggle or maybe a double button PPT remote
• An SPST Power switch separate from the volume control
• 3.5mm Audio output to a digital voice recorder
• External PPT Button input

Hello everyone) my name is Sergey. Im from Ukraine Kharkov. I'm electronic engineer. End i love electronic and music from children years)
I'm love Esoteric, shamanism and psychedelic music best of all.
And we du audio equipment for music like this) also we sell this equipment.

Rilly!

That historical curiosity and other chewy intellectual treats can be found in my Installment No. 8 of my "John Marks' Bookshelf for Lovers of Recordings" series over at Michael Fremer's Tracking Angle.

BTW, Lincoln's favorite opera was von Flotow's "Martha" (pr. "Marta"). The tenor's aria of brokenhearted horror, when he realizes that he has fallen head-over-heels in love with his aristocratic family's new serving girl, was Lincoln's favorite aria. Rilly! Here's my favorite performance.

Lincoln's love of opera was no closeted secret. Hostile newspapers complained that he attended the opera during wartime. Lincoln's friends funded a performance of "Martha" as part of the festivities for his Second Inaugural. Food for thought (there's more at the link).

Anyway, Book #8 in my series is "Making Rumours: The Inside Story of the Classic Fleetwood Mac Album."

Drama, drama, and more drama.

Have fun!

john

Good morning all,

As per the title I'm after theses two issues of The Audio Amateur magazine. I'm UK based.

Regards

Richard

When designing a valve amp we have to calculate or choose a coupling cap value which with a grid leak resistor forms a high pass filter using the formula 1/(2 * pi * f * r) this gives us the 3dB roll off frequency of the RC filter. I usually choose a low frequency something like 7 - 15 hz. Traditionally the value of the coupling cap gets bigger the nearer to the OP stage, EG 10n/1M from V1 to the phase splitter & 220n/220k.

I've found I build the amp, test it on the bench, all tests ok then give it a listen but find that the LF response is too low or too high , not quite right in other words. So, is there a way, a method to calculate each coupling cap?

Andy.

Here's the Red Diamond Amplifier.

Can someone tell me why will my pioneer DJM-900SRT does get very hot at the back and then cut off one come back on

Not sure if this belongs here or in the line stage forum.

Would @amb LCDuino be a good choice to add on the front end of an Aikido or Hagerman Clarinet? I’m at the point of selecting enclosures for these two preamps and would like at minimum remote volume control, but source selection would be just be a bonus. I do have a couple or relay based selectors I can add a manual control for though.

I have this model that runs with Tina, LT does not recognize it and I found another model from Fairchild. Lib, same.
What to do?

Hello to anyone that reads this hope you are doing well. I currently have discovered upon DIY audio after being interested in getting my own audiophile setup. I would like to first state my objectives:

• To build a complete DIY system (Pre-Amp) (Amp) (Speakers) (Extras such as DAC, EQ's Meters).
• Low - mid but flexible budget system which will out perform the non DIY systems at my desired price point.
• Gain a basic understanding of how each of my (future) audio components work.
• Not an audiophile but I do appreciate high quality stuff, and enjoy having nice things.

Obviously I do not know what my future speakers specs are but I can give you a basic rundown of the space the setup will be in.

1. 11.ft x 13.ft room (however on one of the walls there is a wardrobe sticking out about 2 and a half feet spanning 3/4 of the wall so really the room is 11 x 10.5.ft) also as it is my bedroom I have a double bed sticking out in the middle of the room. This means that I don't have a proper listening space which is sad but I'll just have to make due and wait till I can afford to move out (I am 18).

As far as source media goes it will mainly be vinyl, but hence I mentioned a DAC I would want to have a digital input option as my vinyl collection is small and still growing.

The turntable will be a Technics SL-1200 MK2 which is currently being shipped (going to be a bit of a fixer up,er). Tomorrow I am building a flexy rack to put all of these future components (my mediocre gear will go on it for now).

Hoping this thread will provide some answers for other people like me as I couldn't really find a thread with what I was looking for.

So to cut a long story short I will get to the point with a few questions.

• Class D vs Class A/B for amp?
• If you think I should go for Class D or Class A/B what are some designs / products I should look into?
• What Pre-Amp designs should I look into?

• Budget for Amp is MAX £450
• Kits are preferred but don't mind sourcing individually
• Have some experience with through hole soldering, and have a decent soldering station, but very basic knowledge of electronics theory.
• Ask me any questions you need to to help you, help me.

Kind Regards,
Sgt.Elias.

Edit: I didn't know which sub-forum to post this in, please let me know if it's in the wrong place and I'll move it.

I was looking for subwoofers on the dutch amazon and came across the Earthquake Sound TREMORX-10-4 and found an users manual on the website and the specs seemed to be quite nice. so i wend ahead and entered the ts parameters into winisd and it said that the woofer failed the data integrity check. this usually means that there's a small error somewhere so i go and reset some of the values and check if it still fails the data integrity check. i came to the conclusion that winisd thinks that the mms should be 147.4 grams while the manual says it should be 104.156 grams. to me this seems quite an big difference and makes me wonder if this woofer is even any good.

next i go and try to model with this woofer (with the mms from winisd) and seem to get not quite what i want with an f3 at 37 hertz at the standard configuration.

those 2 factors make me wonder if i'm doing something wrong or this woofer is indeed not any good (for me). that's why i decided to post here.

thanks for reading and hopefully reacting

Trouble shooting a Mk1 version of this little headphone amp, does anyone have a schematic?

Cheers

Just curious if the hyper set swings enough voltage to drive a F4? I am also thinking of seeing if I can incorporate it into my class d amps Eric is selling In the vendor marketplace In place of his input sections.
https://www.diyaudio.com/community/threads/2x150w-amp-module-for-sale.388868/page-34#post-7421384
Bill

hi, i have a Quad 44 and yesterday i realised the power supply was very hot after some hours of listening, all operational amps are opa 134 and opa 604 and i read they have more power consumption, what transformer should i use to replace the original one? how many watts/va´s
TIA

Can someone answer this, please!

Take the example of a cabinet with an identical driver mounted on both the front and rear..one connected in reverse polarity and therefore a dipole.

Obviously limited benefit over one driver except the benefits of only using the front of the cone and in push/pull to cancel non linear distortion. Downside, the distance between the two limit the bandwidth you can use.

But you still have an almost free air condition..and consequently the steep impedance spike at resonance....I'm getting there..be patient!!

One could just divide the cabinet and fit acoustic resistance (felt) to increase the Qt of the system and damp the impedance...

Ok..here's the real question. If I put a port in the partion, it would be seen by both drivers which are in push/pull..so I am thinking we still have isobarik condition in the cabinet so there is no pressure change across the open ends of the port (or is there? )..Would the port still resonate at a defined frequency and be able to be tuned to damp the driver resonance..

Ok, that's it...thanks for reading!

Cheers....

What should I call it?
So far it scares people. The usual reaction is “what is this about!”

See attached screenshot of the "Product" filter category for the "film capacitor" category on Mouser. Do these options mean anything by them selves, or are they just shortcuts for other specs like operating temperature, tolerance, ESR, etc?

I have 2 model 1`s, a first and second generation with AUX input. They both suffer from the notorious tuning capacitor failure were it`s nearly impossible to tune in a station due to the large amount of noise while tuning in.
I decided to purchase a couple of replacement Varicon capacitors from an Ebay vendor that claimed they are original Tivoli parts.

Varicon capacitor for Tivoli Audio Polyvaricon | eBay

Anywho, I finally got to installing them but there are some issues. The good news is that the crackling and noise are gone but now, the frequencies displayed on the dial are waaaayyyy off.

Actual 107 FM shows up near 97. Dialing the Tivoli down, it will tune in actual 105 FM at around 95.
Tuning down below 95 doesn't seem to catch anything. Tuning the Model 1 up to 98 brings in actual 88!
Going further up to 106, actual 93.5 FM is tuned in. At the very top of the dial, actual FM96 is tuned in.
AM stations fared a little better though, actual 690 was only off by a bit.
Both radios have approximately the same issues.

When replacing the Varicon, I was very careful to install the new ones in the same orientation as the old ones. Now, I suppose it`s possible that the new Varicons may not have been ID`d properly that is to say, the clear plastic covers can be oriented 180 degrees relative to the tuning capacitor assembly.

Assuming that the correct part was properly installed, could this be an alignment problem? I considered rotating the entire varicon assembly 180 degrees but I thought the prudent thing to do was to ask here before tearing into the disassembly once more which is a PITA.

Hi,

Some time ago, I prototyped a modified version of Acaudio's UGS module, and showed it here as I was very pleased with the sound 😀 .
But I encountered some problems when using it as an Unbalanced to Balanced converter :
the two outputs were of opposite phase, but the peak to peak amplitude was slightly different from one output to the other...
I investigated a bit, and it appeared that this phenomenon was due to the common-mode feedback resistors (R5 & R6 on the linked schematic),
whose value was too low.

So I moved from 4K75 to the hundreds of KOhms (namely 180K) for these resistors, and it cured the problem.
But unfortunately, this modification had a negative impact on the absolute output offset stability,
which began to wander too much for my taste.

This stability is mostly related to the thermal stability of the output mosfets, and their dissipation being quite high,
I began decreasing their bias current (increasing their source resistors).
The offset tamed down, but the sound was worse... Some veil on the highs.

So I searched for a solution allowing both to keep the high bias and to lower the mosfet's dissipation.
It ended up by using a second cascode on the output stage :



A bit more complicated than the first version, but it met my needs.
The offset was down to what I was used to (+/-1mV), as for the sound. It was even better,
with a greater extent to th top of the spectrum, some added speed. I was a lucky man 😀

Then I stumbled upon one of Nelson's crumbs on the UGS, and I immediately wanted to try it 😉
It's based on the use of current mirrors for the "output stage" (the level shifters), instead of mosfets.
Being born to the world of High End using mostly mosfets (thanks Nelson),
it was somewhat conceptually hard for me to move to BJTs, but I made the step,
and here's what I tested :



To go straight to the conclusion, I must confess that (for me) this version is by (a lot of) far superior to the mosfet version, cascode or not.
Ultimate speed, added life to the music, truth everywhere, instrument location, dynamics, widening...
Wowwwww... What a beast !

And from the technical point of view, it's a pleasure. I love the elegant simplicity of the design.
And no more need of common-mode feedback resistors... Provided that the transitors are thermally coupled,
it sticks to 0V, typically 0.1 to 0.2mV, both relative and absolute, without any parts matching.

I've still got some test to perform, e.g. to see if a lower current gain of the mirrors has effect on the sound.
This would allow to dicrease the dissipation, and may be to avoid a thermal coupling.

Just for the pleasure, the whole family 😉



From back to front : The original version, cascoded mosfets, and current mirrors.

And at last, a very warm thank to Nelson for allowing us to have a taste of heaven. Many many thanks 😎 😎 😎

I have for sale 4 pieces 0,47uf verry little used top pio caps from Ampohm.They are in like new condition.Leads are about 40mm long.This caps are truly top notch in sound,verry transparent,musical and never harsh.The sound is so smooth and just musical.Plese look online for positive tests.They are way betther than many other modern PP and Pio caps.For verry little price you have a chance to have truly verry good sound.Price is 60 euro for all 4 plus shipping.

A few months back. I bought an XDUOO MU-604 DAC. I installed the drivers from the Audiophonics web site and all was good. At least for a while!

I then noticed that both channels started clicking when playing music or watching movies. This only happened on USB, however the optical and coax inputs were fine. I tried both usb inputs and several different usb ports on the pc, but still no good. I thought the usb board may have gone faulty so I contacted audiophonics for a return.

Sadly there was no fault found, but they sent a replacement anyway in case it was an intermittent fault. When I got it back, more clicking!

I uninstalled and reinstalled the drivers to no good effect. I had already checked all my cables etc. and was a bit perplexed.

I therefore uninstalled the xduoo drivers and deleted all the files and then reconnected and allowed it to install the native Windows 10 drivers. Problem solved!

It looks like at some point some new windows components have caused some slight incompatibility with the xduoo drivers. I installed asio4all so I could use asio playback as this was part of the xduoo driver functionality.

I thought I’d mention this in case any of the projects here use the same chipset drivers as the xduoo and may experience similar issues or if anyone with an xduoo DAC has a similar problem.

Good morning.
A few months ago I took possession of a Naim nap 110 which has undergone maintenance over the years.
The photo shows its interior with tabs.
One channel has original transistors, while the other has 2N-3055s which are similar to the MJ15003s (RECOMMENDED) but not the same. I would like to replace them with two MJ15003s to start with.
The capacitors that were originally all tantalum are now electrolytic in many parts. I would like to put them back in their place.
How about?
Do you know the exact values of tantalum capacitors?
Other advice will be appreciated.

I would like to clarify that currently the final also plays discreetly and on for hours.
Only the idea of bringing it back to a more original standard
makes me calmer.
Greetings

I have the 5.3MS drivers, and have been quite impressed. However, in a small sealed box they (of course) can only go so low with conviction.

I'm now considering a lowish extension down to around 200hz crossover (in a WAW). The 5.3 can do this but I'd like more impact/SPL than a little cone is ideal for. So the 7ms is quite an appealing step up. My question is how much does that sacrifice the top end?

For perspective, I also have the 11MS and they are surprisingly good at the top end for their size... until compared to the 5.3 or a decent tweeter. So I/m wondering if a middle ground like the 7ms may be nearly as good up top? If not, then a tweeter-assisted wide-range might be an preferable - crossed above our ability to discern very much about location etc..

Thanks,
Kev

Hi all,

I am restoring/repairing a Bang&Olufsen Beomaster 2400.

After a minute or so, I get a hum from tuned station, no hum between stations. Hum is propably 50Hz.
I have recapped all electrolytes.

I suspect something wrong in the stereo decoder section. Could it be the IC itself?

Has anyone any ideas?

Best Regards,
Jan Sjöberg

Sound Code Systems. the LA Glam Slam amp of choice. these old Mosfet PA power amps were awesome in their day. they use the famous and well loved Hitachi Mosfets. I think the same used in Haflers?? I have had this sitting around my shop for a dozen years or so and just never got around to doing anything with them. I they both worked years ago when i last tested them. the larger 2600A i used about 3 years ago for a bit. but both should be gone through and cleaned up etc.

the 2600 $150
the 2350A $100

plus shipping and they weigh a LOT!

I have some 2-way 12” with a cd / horn LCR speakers that I DIY’d that I believe have a terrible resonance due to the dimensions of the box and the 3/4” MDF board (bracing too).

I would like to put some kind of dynamat adhesive mat and some egg crate foam type stuff behind the drivers AND still put some stuffing back in, what do you guys recommend for doing this?

The tester is new and never used.
Selling if for a friend who did the wrong purchase.

Sold

Hello all!

Abacus Audio Aikido Tube Preamp. This is the 6GM8 version, not the 12AU7 version. The preamp has the John Broskie Aikido tube preamp PCB - the LV Aikido circuit (low voltage). The 6GM8 (6N27 / ECC86) tube is perfect for this low voltage application - 24 volts B+.

You could drop in another tube like the 6922 or 6DJ8 (do not put in a 12AU7, you will destroy one of the two triodes), but those tubes are best run with higher B+ Voltages...the best tube is the 6GM8 (per Broskie)....and unfortunately they are not cheap.

Comes with extra 6GM8, and programmed remote that does volume, input, power, standby and mute.

Audition possible for those in Chicago area. How's $525 for a ready to go Aikido?

I wanted to get a taste of Andrea Chiuffolis Amplifier End but the Interstage Transformer is a bit on the pricey site for a mear test.
He uses the LL1671 in Alt Q configuration parallelling the four primaries and putting the secondaries in series.
Lundahl ommits so much relevant data that I as a novice can not find a substitute.
In my application I use the amp only above 100hz which should make it easier to find a cheaper substitute I think.
Any help is greatly appreciated.

Klaus

I have been listening to Dynaudio C1's crossed at 250Hz with my low end coming from DIY Woofers with ScanSpeak, 32W/4878T01 Drivers. Sound is clean, detailed and quite amazing..............

However, I am longing for that Live, Horn Dynamic Sound that I am missing in my current setup.

I was thinking of just buying Klipsch Forte or Heresy IV's and get this out of my system, (or stay happy with them), however, what about DIY?

I can use my existing Woofers for the low end and just build the cabinets for the mid and tweeter drivers/horns........

I have been searching a proven receipe and just get more and more confused.

I am thinking to use active X-Overs and discrete amps.

Can a driver/horn guru on here make recommendations for me with respect to what drivers and horns to buy and build?

Thanks for supporting this ride............

So I built a pair of Crites CornScala speakers (Klipsch Cornwall knockoff), and they sound great but I use them in my basement when I work out, and I'm 90% of the time standing up.

I've noticed the woofers sound anemic when I'm standing up, but are fine if I sit on the ground. I figure I would need to raise the speakers at least two feet off the ground. Chains above arent an option.

My question, what is the best way to go about this? I was thinking using plywood and cutting 4 big square holes into each side? I'm afraid If I make a closed box, it would resonate. Am I overthinking this?

Any tips welcome, thanks!

SOLD!

These were pulled from a working active loudspeaker project. Quantity 2 available of the 2BG version. Excellent condition. Without power supply or SIM card.

$100 for the pair, including shipping. Would prefer to sell together, but will also consider selling individually for $60 each shipping included.

NOTE: If you need a SIM card I can offer a new in packaging Samsung EVO plus 32GB class 10 for $10 each or $15 for two. Compare to:
https://www.amazon.com/Samsung-MicroSD-Memory-Adapter-MB-MC32GA/dp/B07F24ZBPV/ref=sr_1_5

Hi, like to know if anyone has the schematic of the krs200 , how to tear down to upgrade the caps and bias the trimmers.

Thanks for help

In like new condition pair Visaton TL 16H supertweeter for sale.Verry little used.Price 300 eu plus 20 eu shipping inside EU.

I’ve had a Laney VC15 for about 10 years and recently it has developed a loud pop on power off. It’s about half a second after the switch has switched, so I don’t think it’s the switch caps. The electrolytics look ok, and the amp works well.
If I pull V1 the noise it there. If I pull V1 and V2 it stops.
Any clues where to look?
Thanks