I tried to find lowest input capacitance, SIC Mosfet
https://fscdn.rohm.com/en/products/databook/datasheet/discrete/sic/mosfet/sct3120al-e.pdf
https://d3rx8y505vv2z0.cloudfront.net/uploads/2021/05/C3M0120065D.pdf


I don't know how hard it will be to get them make MUSIC ,



Wont lie SJEP120R100A and SJEP120R063A were something special

And known points ... Question is, if you have an existing passive crossover with known point and slopes, why doesn't simply programming the matching active parameters work the same? Is it even a good starting point?

Well, the pcb is on revision 2 but I'm really pleased to see it belting out 36Vrms into a dummy load and not breaking a sweat (I was). I thought now's the time to over test it. The pcb is expendable as I have plenty more for the batch I need. Gave it 15% over volts on the supplies and wound the frequency up to see where it would start to fall off. 50k... 60k... 75k.. Hang on, what's that smell?. Looked round to see what resembled a volcano coming from the pcb, so quickly killed everything (by that point 80kHz @ a tad under 40Vrms). The offending component was a 10ohm 3W 2512 surface mount resistor. Then it dawned on me. That resistor is in series with a 100nF C0G cap as an RF filter on the output... and I just put a lot of RF through it... I had stupidly forgot about it when I wound the frequency up at full power. The most amazing part is that it still measures 9.3 ohms. I tentatively restored power and the amp was like nothing had happened. There's no better way to get confidence in a new design than to over-stress it and then soak test. Just remember that output filter...

Quick question,has anyone encountered a noisy (intermittent static/pfft type noise) with any of their parts?
Amp is making some noises thru the woofers only,both channels,no signal.I'm fishing and hoping it may be something else.

Right now, I'm looking at two options for a TMW concept:

1) Try to use an additional driver to "steer" the off-axis response (really, create a cancellation/lobe so the off-axis response at just the bounce angle is at a significantly reduced output). I'm not sure if this is possible but I'm thinking I'll try to figure out VituixCAD for this.
2) Put an absorber/diffuser in the bounce path. This would seem to be the easiest option but it's more wide-band than I would like and will look physically large and ugly (basically an absorbing bucket...)

The one option that I do not wish to pursue, in my particular situation, is to put the woofer right down at desk level, because that increases the c-c distance to the midrange beyond the limit I've set. I want the tweeter to be at approximate eye/ear level, with midrange as close as possible to the tweeter.

Thoughts?

I am interested in building a preamp by combining a line stage and phono stage in one box. Specifically, I'm looking at the Aikido boards from GlassWare Audio Design:

Aikido Octal Stereo PCB
Aikido PH-2 Phono Stage

The descriptions for these two boards both suggest their PS-21 power supply. "Great" I thought, "I can use the same power supply for both boards".

I assume it can't be as simple as branching the various +V rails to the two amplifier boards. I imagine I would have to increase supply capacity (transformer? rectifier capacitors? both?). I also assume there are grounding concerns to address. Are there other issues with such an idea?

I just noticed this while browsing the Q-component catalog.

https://qcomponents.ca/collections/...-misco-165-fr08-04-6-5-8-ohm-full-range-93033

https://store.miscospeakers.com/8-inch-single-driver-loudspeaker-93087

Anyone has experience with it?

Looks pretty decent with balanced TS parameters, at least the way I like. 🙂 A bit on the pricey side, approaching comparable - at least on paper - Fostex and SEAS units, for a company not usually associated with hi-fi, though some recent offerings are going this way, namely the titular Oaktron and the XBL2 woofers.

Arcam products automatically turn off (spontaneously).
I found the problem. The reason is the destruction of the soldering of the Relay contacts in the power supply unit. As an example (picture) repair of the AVR 300 receiver. I hope I helped

Hi:

I have a handful of old axial (date code 7932) TRW film caps, series JF-91. No info on the successor company ASC's web site, no response to inquiry.

I figure at worst polyester/mylar...

They don't strike me as 'large', so I doubt they are a better film type.

For example, marked
JF-91
0.22 10%
100 VDC
162610

9.5 mm diameter, 25 mm length.

Unless someone here recognizes them specifically, um, I'll call them 'film caps'.

Thank you!

Murray

self osce smps green core about 1inch

Hi everyone,

I’m new here, just wanted to share my recent build. The goal was to build a funny looking amplifier based on a simple and reliable tube design and that’s how I’ve discovered George’s SSE. Due to the weird component placements, extra parts in the signal path (old helipots in place of R17 and R27 and meter shunts) and much longer than normal wire runs I didn’t expect much of the sound quality. However, to my surprise, the amp is dead quiet (cannot detect any hum whatsoever) and so far I haven’t noticed any problems with the sound either (still have to try it with a better speakers though). To my ears it sounds great – a truly bulletproof design.

Thanks George, I’ve had a lot of fun building it!

For sale is this pretty much unused 3e Audio 3 channel amp. It was tested.

£35 plus shipping.

Hello to all, new bee here. I recently decided to build an f5 turbo and used 6L6 build guide as a template. Everything seem to work out fine but i am left with a low bias. I used a combination of what was posted on the build guide and via you tube per roberts f5 turbo build of the dual Antek 6224 set up. ......attached are some pics of the build....is there anything i can do to increase the bias? everything is rock solid on my meters...very little drift,but i cant get past 250mv ...any help would be appreciated....also i dont know what fuses to put in they all seem to blow when i intially powered up. ...i have put in some 15amp fast blows for now.

Power amplifier project recommendation

Hello,

I'm building an amp project.

I've been testing the LJM L7 and I really like the sound it has.
This one has IR250 and IR9250 mosfet transistors, very low distortion and an SNR level of 97db.

However, browsing the internet I have found the LJM L10 and also the LJM L15.

The LJM L10 uses conventional thosiba 1943 and 5200 transistors, but in this case the SNR is 110db, much better.

The LJM L15 uses 3 pairs of ir250 and ir9250 type mosfet transistors but the SNR is 97db.

The distortion is very low in all models, I do not consider it important in this comparison.
Power is not very important to me for domestic use.
I would like to know if you could advise me which project has the best sound quality, and if this project could exceed the characteristics of a commercial amplifier.

Thanks, and greetings to the forum !!!

Anyone can tell me the difference in sound between these two different type of regulator?

Title says it all. I tried the Crown xls2502 and I dont think it has enough grunt. I'm curious what others are using and if they are happy with it.

Hi.

I got some speakers on Black Friday for like 7€/piece. So I got 4 Tangband W6-658A mids and some TB 25-3025 tweets.
I decided to make a t-line for the mids, as I have never done one, and I'd like to get the most bass extension out of these, to not necessarily need a sub.
I have space, about 50-60l seems good per speaker and seems to be enough also.

Here is a somewhat final design as for the parameters:

I noticed that I can make the line shorter and overall smaller by making it larger at the beginning and smaller at the end, so I get a tuning of about 44Hz with only 53l.


But now the problem. I planned on making these floorstanders, to get the line output at the floor for the most boundary gain and to not need any kind of stands to make them more rugged.

But the line is so short, that I can't get any folds. Mostly like the one 90 degree fold for the "port" output to come out at the front.
But I have heard that some amount of folds is good for t-lines to mask those resonances. Then the top end would be a lot deeper than the bottom, also making them more unstable, but I didn't want the port up top.
I'd like them to be about 1m tall, but taller could also work.

Should the output "port" be at the front or rear? I'd think the front as I'd like to possibly place them closer to the wall in the future.

So the problem really is, how, if at all, should I fold these and make them?

Cross pollinating from another group in case anyone might be interested:
https://www.eevblog.com/forum/buysellwanted/free-transformers-from-vintage-test-equipment/might be some closer/more interested here?

Contact, uhh, let me know, I can message him for you I guess. If you don't want to log into EEVBlog.

Cheers,
Tim

Surprised this hasn't come up before. Ronnie Spector ("Be My Baby") passed away on January 12th, 2022.

I didn't realize this -- she was Cherokee by descent from her mother!

Some youtube:

Brian Wilson reacts:
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Ronnie on Letterman (1983-2010)
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Ronnie Spector and Bruce (1976 NYC Palladium)
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In my project I'm using a 18sound 8mnb420 in the 100-1620Hz in a closed box. In Vituix simulation it appears that a volume box of 5 litres will do the job. Being the high pass xo a 6db/oct and the low pass woofer filter a 12dB/oct am I right ?

I have not been involved in PA systems for at least 20 years. The thinking back then was to take the bass out of the monitors. The bass player has a Marshall 4 x15 2 feet away so fold-back was focussed on the upper frequency ranges - vocalists need to hear what they are singing.

So, I'm watching a Trevor Noah video on Youtube and I'm wondering why he has at least six subs on fold-back?

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Sold.

Good afternoon everyone happy New Years. I happen to be a long time supporter and fan of the woofer tester # 2 buying 3 of them in the past and selling them cheaper to a few Acquaintances of mine to help them out. So I noticed that they never updated past windows 8? Now it’s windows 11. The reason am posting this is am looking at my options of getting a new computer and was wondering if anyone has direct contact with them? I have e mailed them a few times no answers back? I know they have some awesome programs out. I’m just bummed because I want to step up but, am afraid it will be a paper weight in a year or so? My windows 8 computer is very slow and takes to long to update every time Ugh. So if you know anything please let me know? Thanks for everyone’s help. Jeff

I'm trying to complete installing the innards for a DIY Remote Volume+Input Control I bought on eBay by putting them in an enclosure which has a front panel that is cut out to fit the LCD display and a back panel that has cut outs for the four RCA-jacks.

These are the specs I've been given that will fit but I'll settle for the enclosure and I can do the rest. Prefer a non-metal enclosure.

External dimensions: 273x190x64mm
Internal dimensions: 262x175x55mm
Accessories: Four machine feet, all aluminum knobs, power input sockets, screws

Can anyone recommend a supplier/vender/source?

Attaching three pix: two of the enclosure kit, one of the innards.

Hey all! I have a Tandberg TCD 310 that I've been renovating gradually. Upon what I thought was completion, I noticed that Dolby only works on one channel. When I switch position of the boards the problem follows with it, so there's where the fault lies. All the electrolytic capacitors and some tantalums (in the signal path) has been recap'd. I've also replaced all transistors on the faulty board without any luck. Anyone has an idea where to look next?

I read lot of things about FRD files, but lot of these are old, so, in 2021, what is the best or simple software to make FRD files? I'm planning to buy a miniDSP UMIK-1 microphone and a DATS V3 box.

Thank you! 🙂

Hi!
I would like to use NTC as soft start for my SS Tube PSU.
I have some questions:
Does anybody have experience with NTC in tube PSU circuit?
What is the best way to use a NTC Thermistor for Soft start?
1. NTC connected before the power transformer. On the primary side.
2. NTC connected after the power transformer. On the secondary side, which goes to the B+ supply.
Some people says soft start is needed only for B+,
another says for heather too,
or even for both (B+ and heather),
or even its not absolutely needed...
For me the most logical would be soft start for both supply, so the NTC should be in the input AC line.
Should I use in this case CL-60 or CL-150 NTC?
The transformer is 200VA and the AC line is 230Vac.
Greets:
Tyimo

Hi,

I have these drivers and want to build a decent sounding enclosure for 4 x drivers, and 2 x drivers ( 2 diff projects) any suggestions / advice or plans

Thanks

Please post all problems using the store in this thread.

Lazy loading not deferring to browser cache on subsequent page loads, hence waiting for cloudflare and scrollbar jerking on some threads for each view.

I have built the RCA tube manual RIAA phono preamp. Sounds great.

I am just wondering about the purpose of that last little 180pf cap on the anode of the second triode. The say to reduce it as you make the interconnect cable longer. Hopefully it isn't critical to the RIAA eq curve implentation.

In a search for particularly long-life capacitors someone suggested that I look at capacitors that have a proven track record in horizontal deflection circuits. They said that horizontal deflections circuits are very tough on capacitors.

Can anyone suggest a brand and series which have a solidly proven long-life in horizontal deflection circuits?



The actual application is in the SMPS of a Tektronix oscilloscope (they call it an inverter). I was looking at UCC KY, Nichicon UPW and Panasonic FM-A series. All are 105C and low ESR. (I was looking at 10mm to 12.5mm diameter for 1000uF and 50V or 63V to get lifetime ratings of 4,000 (FM) to 10,000 hours (KY).) The originals are Mallory of which a number have leaked.

I would like to pick a very reliable capacitor that will never need to be changed again. (Outlive the rest of the instrument.)

Here are some pictures of my DAC, please take a look at it, many thanks!

Quanghao

No year, month, day. it shows for example: Sunday at 10:30 AM. I hope this is not the way it will be. Note: If one hovers mouse over the date it shows the whole date as we usually look at. Also if using the Enhanced print feature the date does not show up. Real problems if trying to save in a chronological order. Only started happening in the last week.

I acquired an Angstrom Center Channel speaker model: Modular Six/C. Instead of what's normally configured as an MTM with tweeter in middle for a center channel, it has one 5" Vifa glass fiber mid/woofer (SG14SG01-8 ohm) with two Vifa soft dome tweeters (TC20SD05-06) on either side in a vented enclosure. It sounds good but was seeking some comments on this TMT layout compared to MTM. Granted an MTM speaker lying down is not the same as an MTM standing up (a.k.a. D'Appolito) and the polar sound distribution (hence lobbing effects) are not ideal in a horizontal position compared to vertical. I understand what the best layout for a center channel is W-M/T-W and that is woofer on the sides of a tweeter above a midrange in the middle. Anyone see the benefits of this TMT config. and if its better or worse than an MTM type as far a phase/lobbing and ultimate speech articulation, etc.? I struggle to see anyone using this layout in a center channel speaker or otherwise...

This is a dual mono amp running in Class A at around 37 watts using
This is the Aksa Lender P-mos Hybrid Aleph boards
. It uses a pair of the SLB power supply boards
A fantastic sounding very clean Class A.
That includes the 2 Aksa Alpha amp boards the 2 SLB supply boards
And the 2 Antek Transformers and the Heatsinks
Asking $680.

I have 2 of these SLB class A
Power supply boards for sale
Perfect quiet power supply unit
For Class A or AB amps
Asking $200 each Or both for $380.

Hi again folks,
I´m coming from marvelous threat open by dimkasta: https://www.diyaudio.com/community/...io-mm-for-30-euros.234544/page-2#post-6881127
Encouraged enough now, I´ve decided to repair my GOLDRING 10-20 and it broken stylus in the... 90´s!!!!
the replacement stylus costs about 175-200 euros, if not more, an amount I am not willing to pay, and now I feel able to look for a cheaper replacement needle. I wonder if it will be the same with Goldring, and their stylus are made by another manufacturer (Chinese for sure) and they only care about choosing the model? The ways they make profit know no bounds.All I need is to find the same type or similar.

After 20 years of being almost complete but in storage, it's time to go.

Pearl phono stage (first one). As you can see, the boards are almost complete. I had some additional components in the same container as the boards and transformer. I can't guarantee thats all you'll need.

The transformer is a Plitron, from what I recall it was very expensive.

$300 obo plus shipping, US only please.

Sorry if this has come up before I've been searching and haven't found much. I have collected a few Crown Series II D-150a amps (all above SN 61000) and it seems channel 1 is usually where a failure has occurred. I don't know the history of the units and I hope to repair them if practicable. I've got one amp that sounds pretty good I use as a reference but on it I find R3/R8/R!0 get notably hot even on light duty. The PCB has heat marks on it as do the other units. How normal is this? I've recessed the resistors from the board increasing wattage, checked output bias/diodes, updated capacitors,, and have the D-150A II service manual to assist. Should these get that hot. Any other tips out there what to check?

thanks '

In preparations for my future amplifier builds I decided to start from a good power supply. For maximum performance, dual mono configuration is a must. But, I felt that this is a waste of my financial resources and planet Earth resources. Two oversized audio grade transformers, huge capacitor banks, specific “sounding good” capacitors, etc. Single regulated linear PS would be better than ordinary dual mono CRC, but I didn’t find any with low dropout, high PSRR, high output current, low noise, low output impedance and good transient response, in the same package.

So, I decided to make a one.
Silly me.
It was not an easy task.

Best approach seemed to be an add-on module for various existing CRC power supplies that replaces resistor in the CRC line and turns power supply in to the regulated one. I had some excellent CRC PS boards with active (synchronized) rectification from prasi (ANALOG DESIGN) and that was a starting point.
Final result is on the picture below and those modules should fit to all CRC PS designs suitable for amplifiers available in the Pass Labs section.



They work, as is without any changes, from 10 to 65 V output voltage and load up to 10 A, with dropout voltage of 0.15 V for 10 A load, PSRR greater than 100 dB @ 100/120 Hz and total noise less than 3 µV.

Diyaudio is a place where wealth of designs is available for free and, by extraordinary generosity of Mr. Nelson Pass, we get for free IP that someone else would charge you an arm and a leg.
Completing design that was not available and that could be of use to someone else except me, the only right thing to do would be to make an additional effort and provide complete documentation, but … not a small baggage comes along with such decision. After some debate with myself, here we go with my small contribution:

An arguably better replacement for the resistor in a CRC power supply - R21 PS module

These are all unused and never mounted.

Power Supply Chokes
2x 3H/500mA - 120 (pair)
2x 6H/250mA - 120 (pair)

Line Level Transformer (Sold)
2x LL7903 - $200 (pair)

Output Transformer - (Sold)
2x LL2745/8mA - $150 (pair)
The LL2745 is a specially designed line output transformer for O1a and #26 directly heated valve preamplifiers.

Hi out of curiosity I decided to try a passive volume control.
The reason was to see if the cd via a dac could drive my amps.
I was hoping for a greater sound stage.
I read as many threads etc i could find on the subject and understand there is a relationship between output and input impedances
Due to that fact and not fully understanding the concept I ordered the cheapest passive I could find thinking if it worked I could change the pot, connectors and rewire for greater clarity overall.

The cd player Rotel RCD02 is listed as 10Ohms output
The dac CA Dacmagic outputs <50ohms 2.1v
The Power amps 2x bridged mono Rotel RB03 input sensitivity is 33kohms 1.0v
The RCAs are Cable Talk Monitor 3 all quite short
The pot used (allegedly) is alps rk16 10k

Plugging in last night I definitely fall into the HF roll off camp so not one to give up just yet I am curious.
The set was able to drive volume with no problems, however there is definitely a drop in HF I understand this should be due to impedance matching.

Is there a way to modify the source, cd and/or dac output or the power amps input to improve the matching which would not detrimentally affect the system if it still is less than favourable?
I'm quite comfortable swapping out caps/resistors.
Could some diy low capacitance interconnects help?
Does the pot have any effect? e.g swapping to a genuine alps rk27 with point to point wiring and better RCA's
Or is this simply a its not going to work scenario?

Thanks in advance Ian

While searching for large amplifiers to begin a journey towards large subwoofers for LFE and musical enjoyment, I cam across a deal for 4 (FOUR!) large Crown amplifiers, 2 CE2000's and 2 CE1000's, included were 2 CARVIN TRX-18 dual 18" subwoofers. I wrote a check and hauled it all home on a trailer.

Yes, they are comically large. As I pulled them up the front stairs, my girlfriend says, "You don't want to be married, huh? " - Nope. LoL !

So, I hooked up both sets of twin 18's, and set one CE2000 on each box, bridged to 4ohm, for a 2,000W RMS potential. Plenty.
I added a ROLLS box to take the RCA to balanced XLR input with a DSP-LF box upstream of that.

My SONY SNR-DN1080 has dual Sub outputs. I cut off those big JBL dual 10's at 120hz HP in the Sony and then manually X-over the big subs at 120Hz LP in the DSP-LF, (plus it's own driver, enclosure, and room correcting autotune).

Deep bass and LFE is amazing.

Question 1; What type of enclosure is this CARVIN TRX-18? It has two openings for each 18, yet it is not a port. A infinite baffle box?? 🤔
Question 2; Having way more power than I need, would I be better served building a sealed or ported box with these 18's ? - or selling them and starting from scratch on a large 18 or 21" based sub enclosures.

Thank you for any advice!!
-Paul

Anyone had any success using this tweeter?:
https://www.daytonaudio.com/images/...me-neodymium-tweeter-4-ohm-specifications.pdf

It's been a couple of months, but I tried this out crossed at 4KHz 2nd order, and frankly it sounded bloody awful. I perhaps should have padded it down a bit more, but wasn't motivated to try. Any hints for improvements, before I consign them to the outer darkness? I bought them based on price, dispersion looks good, & they've got an integral grille. Perhaps the peak in the high teens needs taming, but at the moment they're just confirming my prejudice towards soft domes.....

4x NOS CX301 Cunningham Globe - $120

I have a Kenwood 5-channel that turns on for a second and then turns right back off. Nothing seems to be burnt that I can see.
Any help would be greatly apricated.

Hi there,


When movies have a quiet scene - the sound from the soundbar cuts in and out. Does anyone PLEASE have a fix?

We maximise the laptop/chromecast volume, then control the soundbar volume from there.

I have a TV - Chromecast 3 HDMI plugged in - and the below sound bar connected to the TV with an optical cable.

Panasonic 200W 2.1 Soundbar w/ Wireless Subwoofer
SC-HTB488GNK

The TV is quite old - Panasonic TH-P42S10A.

I have an Oppo DV-981HD dvd player. the player stopped working so I decided to open her up for a look. There is a burnt resistor in position R511 on the power supply board. Since the resistor is burnt I can't read the value. I searched online and no schematic available. There are two colors at each end that didn't get burned. One is gold and the other looks like dark green or black. I tried a suggestion to put a multi meter on one of the leads and the other just before the break in the wire. Repeat on other side. Add the two together and you would be close to the value. The problem is that there is no visible break. I get a value on one side and the other side gets no reading. The exposed core looks like it has a spiral winding. Can anyone help with this?

Thanks

Hey there,
i am trying to find a Amp to drive a woofer which i would like to add to a 2 way system. the 2way should be driven from a valve amp, KT88pp, and i am thinking of adding a woofer like the faital 12pr300 for low end extension.
The two way could be driven with its passive crossover, maybe a active highpass added.
i have also seen some regarded designers following this setup, and it would be a great starting point to play with class d and an active xover.
there are lots of people going for a hypex modules, but there are also some suggesting a IRS2092 sounds better (and costs substantially less).
What surprises me is that a lot of people seem to be happy to simply order some ready made "modules" from china but i wouldnt mind a bit more diy.
is it worth building a class d amp? the L15D seem to come at less than20€ each and i dont seem to be able to even find the chips😕,
any opinions?
cheers
Juergen

Hi all,

I am building a large floorstanding box with removable baffle that will house several different drivers and topologies, first a 2,5/3 way with AL170*2 AL130M and waveguided tweeter. Another speaker that will be built on another baffle is a 2,5 way with 8" HDS 830869*2 and waveguided tweeter, and when im satisfied with the HDS speaker an idea i got was to try out a dome as a midrange between the 8's and tweeter that possibly not going to be waveguided.

Tweeters intended to be tested are my current HDS tweeters in my Elsinore's, SB26ADC, SB21SDC and hopefully also the new DA25BG08-06.

The idea behind using a dome mid os to try out a speaker that is spreading as wide as possible as high up in frequency as possible and to see what that does to the sound against the more common controlled directivity a waveguide gives, as this might be hard to comprehend but all my speakers i have own have had some form of waveguide.

But whats out on the market thats is good? And hopefully somewhat cheap? Lets say preferably under 100$/100€ but if something a bit more expensive is really good then please post it!

Also please post your input on use of the driver and what you think about it!

Best regards from a cold place where the winter is coming...

Hi all-

Do we have opinions on the use of 12AX7 as a cathode follower? Is there something perhaps more appropriate to use in the same socket? Thanks...

Florian Schneider, a founder of german group Kraftwerk is died.

RIP.

Hello there;

I own some AB International 713A amps with built in active crossovers.
I want to change it from 3-way to 2-way like the model 712A.
Does anybody know or own a model 712A to give me some info on the jumper settings of that crossover-pcb.
Seems like the pcb is standard for all models ,just the jumpers change.
Thanks in Advance;

Jorre

I want to put a 2-way kit into Epos ES14 boxes and stumble on a respectable system. See poc - should be able to mount drivers on baffle and screw in

Facts:

° LWH = 12”x9”x19” (20+ liters?)
° Ported in back
° Internal metal bracing
° Simple banana plugs
° Have 80 watt Sony TA-F500ES amp
° Also have ~1962 HK Citation II awaiting McShane rebuild - so tube friendly good

Boxes obviously don’t deserve $1k kit. And I’ll initially have them in corners…haha I don’t care. But occasionally out in “display”.

So I’m hoping to get drivers for cheap. Will adopt used ones from a loving, non-abusive home.

But what?!

Idunn, rediscover ii, sr71, etc? Emphasis on spopranos-basses, and pianos. No ice picks - my ears are…seasoned!

Peace and love to you and families.
Cjrtrio

Hi all,

Good to be here.

Currently, running qobuz through a Node2i to a Denon 3700.

I have a question purely out of interest.

Are there any devices (AV receivers, graphics cards and their drivers, .....) that support the possible 32 LPCM channels of HDMI 2?

Greetings
Günter

Hi guys,
Am planning to build this: Linkwitz-Riley Electronic Crossover still working on the pcb layout.
I am on a college budget and i have a choice of three opamps:NE5532,most expensive and is recommended for the job;TL072,cheaper than the NE;and a "4558",the cheapest option and is flooding the market,used in most electronics from china.
Which will sound decent among the three without eating into my wallet?

How hot do these 3020's run? Got one running into an 8ohm resistive load now and the heatsinks running at 75oc on ~8 1/2 watts.

Eighteen Sound 6ND430
Faital Pro 6RS140

They seem to have many similarities... Purpose, size and price seem to be in the same area.

Just for some general clarity, without considering particular use case, how would you compare these two drivers? Where is each one likely to impress and where is each one likely to disappoint?

I have the following drivers lying around and was thinking of throwing something together since it wont cost me. What do you think of an Eminence BP102, Peerless 830883 and Vifa XT25? alternatives are that I have some 4 inch SB midrange and if that tweeter doesnt work I could buy a Peerless DX25BG60. I did a sim and it looks decent ...

Hello. After some time away from DIYAUDIO, here I am again.
I revive the question asked a few years ago.
It's about the phono preamp posted on TNT.
Solidphono TNT. (They say it is based on the Lehemann Black Cube circuit)
I have built it many years ago and it seemed excellent in its performance.
But I have found a post of a phono pre based on this one from TNT. But with the RIAA network divided. It is still passive RIAA, with some different value. (I have simulated it in LTSpice and the response is almost flat)
I have built it but using the IC THAT 1510 in the first stage.
Of course on homemade PCB.
Sounds like a very good phono stage to me. One of the best I have ever had.
Here I return to the question:
Has someone built this phono stage?
Someone is encouraged to test your construction and see if I am right that it is good?

MM Phono preamp. DIY. Uses 4, 9 volt batteries. Opamps are AD712JN. Angel Polypro output caps. Gold RCA input and output connectors. XLO signal wiring. Silver mica and Polystyrene RIAA caps. Carbon film resistors. Great sounding simple RIAA stage. 50db gain. Will accept High End Audio DIPs.
Top has some scratches from use. With a little paint, it would be a 10. Will ship w/o batteries to avoid extra weight and hassles with shipping batteries.

Asking $75.00 obo. Shipping CONUS only.

In the article How To Wire an Audio Amplifier by Andrew Russell, the author advises minimizing the separation of single ended interconnects to minimize loop area that can be affected by magnetic fields. Carrying this to its logical conclusion, would not a single cable with four conductors provide the optimal loop area? I've never seen a single-ended cabled designed in this way, besides phono cables with a 5-pin DIN connector on one end. Why not expand the concept to an entire system?

I want to present a version of a pivoting tangential tracking tone arm. I will firstly describe the theoretical model without addressing the engineering implementation.
I have pored through the threads on DIY Audio concerned with related technology. I can’t find any projects with precisely the same viewpoint as put forward here but I may have missed some threads. To be absolutely clear, I won’t be discussing a parallel tracking tonearm, but a version of a pivoting tonearm that maintains tangency of stylus in the groove.The tonearm will experience no side thrust and hence will require no anti skating device.

The proposal will not rely on a pivoting cartridge headshell. Tangency can be enforced purely passively with no servo involved, although a servo version can be implemented.

I have tried to keep the principles close to fundamentals, so it can be clearly understood. In the interests of clarity I will present the proposals in a series of posts, each building on the previous, and illustrated with simple geometric diagrams.

I am not yet in a position to engage in detailed debate concerning the practical implementation. However I do welcome any constructive advice. In a later post I will show some videos of a basic working model.

I'm trying to fix an old Technics SL-PJ27A, nothing fancy, just a basic CD player from early 90's. It is based on the Philips CDM4/19 mechanism and so far i had little problems with players based on such swing arm mechanism. This player indeed works perfectly with stamped CD, but with CD-R it can have problems: it reads the TOC with no problem, but then when playback starts it seems as if it is not able to correctly lock on the track and the arm is swung back and forth with the head hitting the plastic wall near the spindle motor. Once it locks on the track, it then plays the CD with no issue from start to finish.
I have already replaced the faulty Philips electrolytic caps in the servo board and both laser power and focus offset are correctly adjusted.
What could be wrong in this player ?

thanks

I am considering making some VISATON Concorde MKIII Cabinets but the recommended driver and crossovers are out of my budget.
I am wondering if there budget options that could work? Thanks

Planet audio has the specs for a single box...
Ported Dimensions:
Length (L) : 14”
Width (W) : 12”
Height (H) : 12.75”
Port: 11.25” x 1” x 22”
Port Extension: 10.125”
Port Tuning: 40 Hz

Following the measurements the opening leading to the port is only 3/4" and the port is 1". This seems off so I would like to use WinISD to come up with a design but I can't find the electro-mechanical measurements anywhere. Is there any decent 600w 8" subs in the $50 price range?

Hi,
I am going to wind a toroid inductor for this circuit,
but would a high permeability core of this type have any downsides?
And is 34 AWG wire fine for this?

Info on core:
Core type MPP
OD 39.90 mm
ID 24.1 mm
HT 14.5 mm
AL value: 740 +/- 8% (nH)
MPP Permeability: 550 (μ)
Wire gauge: 34 AWG

Turns:
16 KHz - 29.9 mH 195 turns
10 kHz - 31.4 mH add 5 turns
8 kHz - 48.2 mH add 48 turns
5 kHz - 67.5 mH add 45 turns
4 kHz - 87.9 mH add 41 turns
3 kHz - 156 mH add 111 turns




Help is much appreciated!

Hey gang,

New here. Looking for some guidance I’ve not found anywhere else…

I’m an audio mix engineer. I’m putting together a home theater setup that I’d like to be able to act as a secondary workstation to my studio and am trying to figure out a clever, cost effective way to pull it off. Here’s the deets:

I’m branching into atmos and spatial mixing this year. My studio will have a proper atmos mixing setup. At home, Im putting together a home theater setup with an Oled + atmos capable avr + 7.1.4 speaker setup. Ideally would like this to stand alone without building it around a computer in any way. BUT…I want to find a way to loop my 2019 MacBook Pro (Big Sur) into the setup and mix/monitor on the 7.1.4.

****Important point: though I’m mixing atmos in the daw, my DAW will NOT be outputting a Dolby atmos stream. It’s not an option even if I wanted it. It will be outputting a decoded stream of 12 discreet, uncompresssed channels…7.1.4. And it’s this 7.1.4 PCM audio I need to get over into my AVR somehow.

The problem is (short of spending thousands and thousands more I cant afford) I can’t figure out how to output that many channels to an AVR. I’ve got tons of experience with audio interfaces, but none with avrs and hdmi type connections. But seems like it must be possible somehow…

Things like hdmi 1.4, coaxial, optical etc reach their channel limits topping out at 8. But e-arc hdmi is capable of tons more bandwidth…up to 32 channels of audio. But I have no idea how to package the 12 channels of pcm I have and deliver it.

FYI, the AVR I’m leaning toward is a Tonewinner at-300. It does everything I need, including providing the right analog outputs IF I can just get the mix over to it. https://summithifiusa.com/products/at-300-16-channel-pre-pro-releasing-soon

I’m open a variety of solutions like: a virtual audio device that outputs to some sort of converter to earc, an inexepsive piece of hardware/interface that does similar, another AVR altogether…something else I’ve not thought of that meets the goal.

any ideas?

New project - inspirated by DynamiKKs Monitor 12/18.
Speakers: one coaxial 10-12" and woofer 18" or 2x15" in sealed box. I like quick bass with a punch 🙂
Active powered by Hypex FA 503 with build in DSP (or FA 253)
What woofer will be best for low bass up to 100-150 Hz? Typical great subwoofer like Dayton RSS460HO-4 18" Reference HO I think will be not good sounding up to 100-150 Hz - or Am I wrong? Any propositons for good soundings coaxial?

Best so far:
FaitalPro 18XL1800 (F3 55 Hz in 95 dm3)
BMS 18N862 (F3 55 Hz in 95 dm3)

Coaxial likely:
BMS 12C382 (F3 136 Hz in 11 dm3) This one need woofer working well up to 130 Hz or so
FaitalPro 12HX230 (F3 94 Hz in 40 dm3) This one need woofer working well up to 100 Hz or so
B&C 12NCX (F3 88 Hz in 60 dm3) This one need woofer working well up to 100 Hz or so

DynamiKKs Monitor 12/18 (bass-reflex)

Hi Guys
Wondering if someone has experience on the above amp. Price looks good & might be gd for tweaking or modification in future.
Your thoughts pls.

Thank you

Hi,

I have tried a bunch of TPA3116 amps...they all sound OK, some sound very well...

I am ready for the next step in class D amplifiers, thats how I found TPA3255...specs look very promising.

I could not find any DIY boards so I ordered TAS5630B instead...not my cup of tea...to noisy. (I hear a white noise in my listening chair)...

I was wondering why I could not find any DIY boards based on TPA3255...

Any hints?

kind regards,

Tony

Hi Members,

my new NAD adventure with this amplifier that seems to have very fragile traces and solder points has started.
The unit turns on fine, amber LED on then click, click Blue LED stable.....good news.
DC Offset is on the high side, one channel 50 mv other one 100 mv after 10 minutes (not able to adjust it at all).
BIAS Current is good (6 mV) and fully adjustable.
I suspect that somewhere in the feedback circuit something is wrong.
Upon inspection all voltages are present except the minus 18 V and -26 V rails.

I pulled the LM337M and tested it separately in a small circuit to verify that it was working.

Refer to attached pictures, appreciating any feedback.

Thanks

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Hello everyone,
I've had this Denon PMA-2000irv amp from new in 1999. Always well cared for. Wonderful amp, great sound. Love this amp.
However it has developed a couple problems. I believe they are not related but I'll describe both just in case.

The main problem is the amp will just cut out completely for just a couple seconds and then click back on and perform fine. It does not happen very often and when it does it may do it a couple times and then go away. Amp works fine for a week or so and then does it again.
It has a main power button which when pushed in can be shut down with remote. Amp goes into sleep mode with the button pushed in but still consumes power.
I always turn the amp on and off with the button, never leave it in sleep mode.

The other problem seems to be with the selector switch for aux/tuner/phono/cd/etc. Sometimes it will suddenly change selection, clicking from cd to tuner, etc.
I figured it may have something to do with the remote mech and have covered the remote IR sensor with black tape. This seems to have stopped the problem.

I've had the cover off, everything looks really good, very clean, no outward signs of bulging, etc.

I live in a fairly remote mountain village and the closest Hi-Fi repair shop is in Calgary Canada, a full days drive away.
So my main question is if anyone has an idea what the trouble is and whether it's something that can still be repaired these days.
Cheers!

Is there any reason that Left-, Right-, and Gnd need to be kept separate to the preamp? Could a standard single pair + shield cable be used with a 5-pin phono DIN?