Can someone give me the part number for the slide faders on the soundcraft si performer 1

Greetings, Friends. I wanted to share my progress on the little SE EL84 amp I've been playing with.



It's undergone a host of changes since my last update. I've installed a pair of 10w 3.5k OPTs, rewired the output tubes for Triode mode, and rewired the driver stage to mirror @Suncalc 's Marblewood Amp. In fact, I seem to have arrived at an EL84 version of that design. Per the EL84 datasheet, a pair of EL84 wired in triode with a 270ohm Kr will pull 2x 36mA = 72mA. Trying to be frugal as the PT only is rated for 104mA.



And the power supply



obligatory gut shot - Large Orange Caps!



As expected, the smaller OPTs deliver less bass than the 15W, but the amp has such a delightful clarity through the upper range that I don't miss it. I had an afternoon of Joe Pass records that really made me fall in love with the amp. Rewiring the driver stage to the "Universal 4S Preamp" made a huge improvement, thanks Matt for posting such wonderful designs!

Eric Carmen died last weekend at age 74.

https://www.msn.com/en-gb/entertain...r&cvid=49006706bf0447d0ac3d9b6d4ee991cb&ei=24

Hi, anyone have datasheet for uPA63H ?
Are they worth using?. as diff amp
" LTP "

It just occured to me that the PF86 instead of a EF86 migth be a better choice for a low level preamp because the 300mA heater could be fed with constant dc current easely obtainable from 6.3Vac (the needed ca. 4,5V at the heater would leave nice headroom for regulation ). Did any of you use the PF86 instead of of the EF86?

I have four ASUS Essence STXii soundcards I would like to clock together. On my Linux machine.

Does anyone know of a good way to do that?

I've read that clocking can be achieved via SPDIF connections, the original STX had a SPDIF connector for connecting with video cards, it makes sense that if the STXii also has the same connector in the same place it does the same thing, and that it could be used for clocking...
https://www.overclockersclub.com/reviews/asus_xonar_essence_stx/2.htm
"The last two connectors on the card are a 4-pin "Molex" power connector and a S/PDIF header."

That's the best I've been able to find so far, anyone have any ideas?

This amp came in with a shorted toroid, vented C59 and vented C17.

I replaced all defective parts and upon power up the cap C59 immediately vents. C17 cap did not. It is installed correctly, I double checked.

I removed C59 again and checked the pads for voltage.
+ 13.57 on pos pad
- 0.957 on neg pad

The original cap for C59 was 100uf 25v. I installed a 100uf 50v and powered the amp and it did not vent.
I checked the pads with the cap installed and am getting +46vdc on the postive lead and the same reading on the negative lead as before.
This cap is tied directly to Q13 LM317 positive regulator. The in voltage on pin 3 of the regulator is obviously also 46vdc.

D6 and D8 also have the 46vdc on the cathode end.

I am confused as to where this 46vdc is coming from. It does explain why the 25v cap was venting, but not 100% sure how its getting there.

Hi,
Does anybody have experiance with large power capacitors.
Im restoring an old Luxman amplifier and need to replace old 10,000uF 50V capacitors. I cant tell what original once type is !!
I have checked sheets and there are three types I , II and III
Anybody has experiance to advise which Type to use ?
BTW, the Type I is most expensive

https://www.hificollective.co.uk/sites/default/files/2023-07/Nichicon KG series data sheet.pdf

So I got these 1940's tubes in what seemed unused appearance ...I started them off slowly, applied DC heater gently for a few hours, then brought the filaments up to rated voltage (DC) for 6 hours. Then applied B+ and grid voltage at 75% of max dispersion for ~6 hrs.

However, after using the tubes within spec for a week, I've noticed a slight change in appearance - a very slight whitish appearance on some areas of the glass (close to the getter) , where there was crystal clear glass previously.

Should I be worried?

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I am working on a Monster Power MPA 2250 where the left channel is not working. I would really like to find a schematic. Can anyone help with that?

Thanks!!

-Joel

Well, I stumbled across this the other day and thought I’d make a little stereo system for a friend with a disability.

Trouble is, I can ‘t find the power supply which is likely a big wall wart, or I never had one to begin with.

What are the odds of someone having one, or helping me build one? Looks like a 6 pin DIN.

I hate to throw things out…

I have two Sonixs 800x amplifiers that have some pretty bad behavior (significant pops and crackles) on startup and shutdown. I've had two separate speakers now that I've had a scare with from these amplifiers after I had thought they were safe to use.

Could it be as simple as a light switch in line with the speaker wire to disconnect the speakers when I turn each amplifier on and off?

The other day I was exchanging emails with one of our forum’s great members, Bob @flocchini. He mentioned having some SJEP120R100 not being used, and would I like to facilitate a giveaway? Yesterday I received Bob’s tracer-matched SJEP pair, so let’s do this! For my part, I’m including a pair of assembled Pearl 3 boards for a second winner.

Giveaway:

• 1 pair SJEP120R100
• 1 pair of populated and tested Pearl 3 boards

Rules and conditions:
One entry per person (obvious, but worth saying). We’ll pick both winners from the same list, so no need to create two lists. I'll pay for the shipping. As long as USPS will ship to your country/address, you meet the criteria.

How it'll work:
To enter, just copy the list of entrants, paste into a new comment, add your DIYA username to the bottom of that list and post. In 48 hours or so, I'll make a comment saying that entries are closed. I'll take the final list of entrants, paste them into an online randomizer, and the name that appears in the top (#1) position will be the winner of the SJEP pair. The person at the very bottom of the list will receive the Pearl 3 boards. From there, winners simply need to PM me their mailing address and I'll get them posted.

And want to get back to building the Aleph clone (using BrianGT green boards)

But alas, have forgotten much and will lean on this community for help getting started back.

Regards,
Vinay

Hello

I now have some surplus JLH phono shunt feedback PCB's for sale (new old stock) that I purchased originally some time ago
asking £20 each plus postage ( 4 boards are available) I am UK based and would like payment by PayPal

happy to get a postage quote before I post please note one PCB will make a stereo preamp .. plus will provide construction manual via email if needed.

I managed to get a selection of drivers on eBay, I bought them mainly for the Alpair 7.3.
So what would you build, keep or sell (kiss, marry, kill)

Fostex FE126En
Fostex FF 85WKeN enabled by @planet10
Scanspeak 10F/8424G00
Mark Audio Alpair 7.3

Over the last 10 years I have been building and selling all sorts of electronic pcb's and systems.
It started off with a couple of sets of drawers for components.
I now have the drawers plus about 6 cardboard boxes full of components.
As it has grown incrementally I know exactly which component is in which box.
To add to the confusion I have about one square foot left on the bench to work in.

.
This was supposed to be a private project, and I was not planning to publish.
But it is amazing to see people still talking about the AD844 as IV.
That is even though Pedja has published a very similar but discrete circuit quite some 15 years ago.
https://www.diyaudio.com/archive/bl...-out-production-pedja-rogic-ddnf-iv-stage.pdf

The problem with the AD844 is that it lacks bias.
The -Vin node has a Zin of 50 ohm, which implies a bias of about 0.25mA.
Using a 0.25mA-biased push-pull input to convey (say) 1mA current signal can only mean that it has to work in Class AB,
i.e. no longer push-pull as long as signal is > -6dBFS.
And yes, you can improve this by stacking 4x or 8x AD844s.
But it is a clumsy and no-longer-elegant solution, apart from expensive.

Just for fun, we did something more similar to a discrete-but-simplified AD844 than Pedja’s.
It has a bias of 2mA, i.e. equal to 8x AD844 in parallel.
Performance is not comparable to the CEN IV, but it uses fixed rails and has an integrated emitter follower buffer.
Bandwidth & distortion were measured with 2mApp DAC current (e.g. PCM1704), and Riv is 2.8k for 2Vrms output.
For the likes of PCM1796, you can increase bias to 3mA and it will couple with 4mApp without much loss in performance.
For more DAC current, you will have to stack as well, or use through hole components for even higher bias.
We want to use SMD because you can get really-low-noise Toshiba dual BJTs that are easy obtainiums.
And they are monolithic, ie. perfect for thermal tracking.

A lot more fun than stacking AD844’s. 🙂


Patrick

.

Hi, I have some basic training in electronics and I am looking to start my first project (improve a vintage CD player) toward DIY audio but I am on a very tight budget. Here are the tools I have in mind so far
HP Agilent DSO3062A Oscilloscope, 60 MHz, 1 GS/s, 2 Channel ~130CAD
Weller wad 101 digital soldering station ~100CAD

Do you think I can do better with the price list above for each tool? What else do I need to start a project?

Thanks in advance.

Oscar

P.S. I also accept used equipment since all tools I list above are price for used as well.

In a Mesa Maverick, one channel has a fixed tone stack, of the usual Fender design. The other channel has B,M,T panel controls in a similar stack topology.

Anyone ever done this as a basic "voicing" design ingredient?



Perhaps imparts a generic eq similar to this;

Hello,

I have a Marantz CDA-94 lurking in a corner of the workshop that might be worth selling. I've never used such a thing in my stereo system but received one from a client of mine. It needs testing so I'll be hooking it up to an old Meridan 208 to see if it at least works. Cosmetically, it has a few scratches on the wooden sides and a slight nick at the top of its front metal face. Internally it looks fine.

From initial searches in the Internet it appears that this D/A has had a good reputation in the past with at least one restorer adding improved power supply filtering and replacing the existing Philips D/A chip with a better version of the same (two-crown chip). The build is certainly solid, to say the least.

I have two questions:

1) Is there still an interest in this model and is it worth putting on the market at all?

2) Having no optical link in the workshop I am left with using a coax interconnect. For basic testing, is it reasonable to connect the coax digital output of the Meridian 208 to the digital tape input of the Marantz CDA-94? (I seem to be unable to get the user's manual)

I would be grateful for comments/suggestions

donf

Hi,
I've had two heathkit devices that where gifted to Me some years ago. One IO-17 and one IM-18.
I decided to see if they worked today, and the IM-18 jumped to life after I don't know how many years, sadly the IO-17 didn't as far as I could tell.
I'd expected the small crt to light up if it worked.

The schematics was easy enough to find. I haven't found manuals for them, yet.

Anyway, is there any point in repairing the old oscilloscope (I don't have one) or should I just remove transformer etc from it and then scrap it?

Hello,

What rating psu is needed for this, i was looking at this from Mouser:

709-RPS30-24

Thanks

I am going to finally make a jump and start building the my first diyaudio project. I am going to build the F4, but as I have read it is not just a simple plug and play amplifier. I'm gonna need a pre-amp.
Looking in the store I have came up with a few options.

1. The AC pre-amp
2. Maybe a full ACA could work?
3. The Whammy

Or this little spanner that has been thrown in by Nelson.

Can I have good advice on a choice please. One which will happily feed the F4. From what I have read the pre-amp for the F4 is going to be the defining part in the overall sound of this amplifier so I do want to take great care in getting it right first time.
Advice on another pre-amp is welcome or why these are a bad idea.

Hello all,

I am trying to figure out how to simulate a speaker in python.
My basic understanding of this topic is that I should use the Thiele-Small Parameter to calculate values of an electrical network which represents the Speaker (electrical and mechanical part).
Then this network needs to be expressed as an function so we can use it to generate the output for a given input. For example a simple sine wave should show up with some harmonic distortion at the output.

As I am not a scientist, I have no idea how to calculate the values of the electrical network and I couldn't find a good source on the internet that explains it so I can understand it. I hope (and think) that it should be relatively easy to calculate those values from the Thiele-Small-Paramters once you have the right formulars at hand. If someone could point them out to me that would be a great help for making this first step.

Something’s got to give, so this goes up for sale. Nice condition and just came back from PL (remote control repair) with a new double box. I would call it “neutral” sounding…somewhere in between a BA3-FE and a ZM Balanced Iron Pre, but not much like my tube preamp. $2000 plus shipping (N America only) to a member of diyAudio. It will go up on US AudioMart in one week for more $$.

Hello

I allway hesitated to use beta-enhancing emitter-follower buffer between the input stage and the VAS, because of it's reputation to be unstable,

Is it true that it's unstable ?

Thank

Bye

Gaetan

Troels Gravesen Speakers ScanSpeak Discovery-3WC-mkII in a baltic birch multiply enclosure (surface so far unfinished).
Detailed info about the speaker available on Troel's hompage troelsgravesen.dk

GBP 599 (for the pair) for self-collectors in the UK (or plus fuel cost if I deliver and you don't live too far away from Milton Keynes).

These speakers wwere built from a kit from Jantzen Audio in Denmark (level 2 crossover parts).
The enclosure has been built from baltic birch 18mm. The surface is so far unfinished and the buyer can decide if they just want to put lacqeur on top or a veneer.

Comes with the original instructions from Troels.

Scanspeak drivers are
D2608/913000 tweeter
15W/8434G00 mid range
22W/8534G00 woofer

The crossover is built from parts of that Jantzen kit. The upgraded binding posts are the components that did not come with the kit.
I also have applied L-pads for the mid and high range, but you can unplug those if you like the original sound better.

because of the weight and fragile nature I cannot ship these speakers via post.
Collection in Milton Keynes is an option, I also can deliver by car within a range of 200 miles around Milton Keynes (at fuel cost).

RB-TB TA-3020 1.2Kw class T amplifier for sale 160€
Genuine working Tripath evaluation pcb board with heatsinks mounting screws not supplied.
Tracked shipment to European union
Skematics sended together with articles.
Payment by PP
If you enjoy this kind of stuff check my stuff related:
https://www.ebay.de/usr/dialedinmusic?_trksid=p4429486.m3561.l2559

I need help with identifying a resistor (R53) from a Kicker CXA600.5

I fix amps as a hobby and got this Kicker CXA600.5 for free and do believe this missing resistor is the problem.
I traced the remote circuit and it lead me to R53. If anyone has a schematic and willing to share, I will be so thankful.


Thanks
Jean

Does anyone know if an SAE 2600 form Japan can have it's transformer wired for 120volt operation?

Hi Guys. Apologies If this in the wrong section I'm new here 👋

I run a party function band for weddings and corporate events. It's a 5 piece band & consists of Drums, bass guitar, keys, electric guitar and a lead vocal (keys and drums do backing vocals) we do events of around 250 - 350 people. Would be great if there were speakers that could do 250 -500 people in the price range but not expecting miracles.

I recently bought the Yamaha DBR 15 tops and after two weddings and two separate sound engineers telling me they are not loud enough. I caved and sold them.

So now I am after some new speakers that are louder. I've seen the Alto TS415's at about £380 per speaker and claiming 2000 watts. Are these any good? Or are there better speakers available for the money. I say right now I have a budget of £5/600 PER speaker to play with.

We don't currently use a sub, but will be looking to add one at some point ( no idea when ) so need some that can cater to the events we do for now with just tops.

I've tried to look into RMS and watts and some speakers are louder with less power ect but it's just too techy for me! Lol

All advice appreciated

Thanks

I would like to buy a set of Toshiba MosFet for BA-3 preamp w/o spending $$$.

I have a new set of Kimber Kable PBJ 3' interconnects I would trade or sell to fund the MosFet purchase.

In Michigan USA.

Thanks

Anyone no the part number or something I can used for the outputs mark D1

Hello all
I have all the drivers for the Audax A 652 designed by the famous Vance Dickason. It's been a long time and I want to know if it is really good enough to spend the time and effort building it.

Audio-Technica’s Tube Headphone Amplifier for $108,000 - Is this price still normal?

Use four Takatsuki 300B power tubes, ECC83S gold pin small-signal tubes, amorphous-core silver-wire Lundahl input and output transformers, dual-mono configuration and a fully-balanced drive design.

What do DIY tube specialists say about this?

Audio-Technica’s $108,000 Tube Headphone Amplifier Must be Heard at CanJam NYC 2024
https://www.ecoustics.com/products/audio-technica-narukami/

SOLD

Greetings! I have a Hagerman Clarinet preamplifier for sale. Sold originally as a kit, I purchased it from the builder some years ago. I used it in my main system for a good long while. Sounds great, holographic, smooth yet well detailed mids and highs. It sports 3 inputs and two outputs. In fine condition. Didn't think I'd let it go but I want to go a different direction with my system.

Will come with a pair of Amperex 12AU7's, and a Phillips 5Y3GT rectifier tube. The rectifier has a fancy Herbie's Audio Lab tube damper installed, which I will include.

It was a stock build when I picked it up. I did upgrade it with Sonicaps where appropriate. I also performed a mod that was endorsed by Jim Hagerman that further improves the sound by reducing the noise floor. This mod is detailed here - https://www.audiocircle.com/index.php?topic=75735.0

$425 shipped to conus. You may notice in one of the pics that transformer wires are disconnected, this has to be done to remove top cover (which I did to service it). Wires were then reconnected, unit was tested.

Like in the encircled part of the schematic.

Hi,

This is a build thread of a speaker system for my living room built on the unitized image wavguide design from Patrick Bateman: https://www.diyaudio.com/community/threads/unitized-image-control-waveguide.319698/page-16

The waveguide being used is constant directivity and offers about 360Hz-20khz range at 96db/w/m using 4 midranges and one tweeter. I went off this design because one of the best speakers I ever heard were the Lambda Acoustic Unity's (licensed from Tom Danley). They did everything right, so this design has similar performance in a smaller waveguide.




- I need the bass cabinet to be dynamic, loud, crisp and have a wide sweet spot. My musical tastes are all over the place, rock, fusion, synthwave, jazz, etc.. Metal is the most demanding as it needs to have crisp kicks and snare along with the wide bandwidth of the rest of the instruments. To find out what freqeuncies need special attention, I took a spectrum analysis of a demanding track "God's Equation" by Pagans Mind as shown below:


As you can see, a substantial amount of musical energy is focused in between about 350hz to 40hz. Kick drums range in 40 to about 100Hz, snare peaks around 193hz, with activity up to around 425hz. Toms focus around 105 to 158hz. This explains why I always liked a higher crossover frquency in my car and never liked the 80hz, it crosses over in the middle of the kick drum. The good news as the around 300 - 400 hz, there seems to be less peaks for various types of msuic of that style, so a crossover can go right there.

- The speakers need to fit both sides of the fireplace in these areas for the WAF to be high (Wife Acceptance Factor) and would be disguised to look like a radiator (like on the left) or a cabinet of some sort. I have a space of up to about 32" long x 18"deep x 25"high. It could be up to 30" if the design has to use that height. The idea is to have the horn sit in it's own box on the top, which brings it to about 30" anyway.



That being said, these are the constraints and objectives:

1. Bass bin that covers 40hz to 400hz,
2. High sensitivity around 97+ db/w/m. Why? I don't know why, but for some reason big speakers sound more dynamic, even at lower volume levels despite the math showing the same output level.
3. Fit within an area of up to about 32" long x 18"deep x 25"high (81cm x 45cm x 64cm). That a volume of 8-10 cu. ft (235L - 283L) Must be box-shaped, this will look like a cabinet or radiator cover with paint and "creativity".
4. MiniDSP, FIR filters, Active Filters are all ok for the bass cabinet. The waveguide would ideally remain passive.
5. The waveguide and be a part of the cabinet or separate.
6. I am knowledgeable in work working to cut and glue panels.
7. sound dynamic at both lower and high volume levels. I typically listen around 85db-90db. I don't plan on blasting concert levels, but want the option.
8. I am open to any and all ideas to achieve the objectives above, breaking conventional rules is ok. 🙂

Some ideas that I have been thinking about for a while:

• Open baffle with two SB Audience Bianco-15OB350 15" Open Baffle Woofers per side. Maximum distance I can keep drivers from wall (at the baffle) would be 18". *I have tried this approach about 12 years ago with early 15" Acoustic elegance dipole woofers on sale. I remember good clean bass with one 15" woofer, so much that it occurred a single one woofer would have been ok, even being close to a wall. That was the "rule breaker" concept as it had the best bass I ever heard in terms of quality. I don't remember regarding dynamics. I had used DSp at the time with a Behringer feedback destroyer unit.
• Sealed cabinet with a 6ft. space using a single SB Audience Bianco-15OB350 15" Open Baffle Woofer Joseph Crower had good success with this, as it showed good promised with critical damping. https://josephcrowe.com/blogs/news/...y-15-2-way-monitor-using-sb-audience-products I was thinking adding resonant chambers inside to damp the impedance peaks like the Hegeman enclosure design from this thread: https://www.diyaudio.com/community/threads/3d-printed-metamaterials.360739/page-5
• Front loaded horn similar to the University Classic, but would need to be reshaped to fit the 18" depth, not sure this is practical for 40hz-400hz. Maybe something like William Cowan's Horn Sub Jr., but with a side scoop to make it front firing: https://www.cowanaudio.com/hornsubjr.html
• Karlsonator / Karlson cabinet of some sort. Freddi speaks highly of these cabinets, but it would need to lay on it's side. They don't simulate well, but I hear lots of praises for it's sound.
• Front loaded bass refelx like Altec A7, but not so large. Joseph Crowes awesome 1798 cabinet looks VERY promising to work off of, but it's too big for my space. However, maybe squashed down/ isobaric loading and with Onken Style vents / passive radiators could do it in the volume I have to work with: https://josephcrowe.com/blogs/news/bass-cabinet-no-1798 I could integrate the waveguide into the top part of the woofer horn.
• Slot Loaded open baffle, or slot loaded closed - Brings down distortion, but concerned with frequency response about 250hz (maybe not an issue?).
• Something Wild and Different - Hybrid Front loaded horn with tapped horn aka Cyclops style tapped horn? 6th/8th order band pass? Front loaded Horn with woofer feeding a Paraline lens that goes into a conical horn?

I'll be going over some simulations to see what may be possible. I would greatly appreciate anyone's input - any and every suggestion would be greatly appreciated!

Assembled, tested and adjusted. Plug and play after it's put in a case and connected. This come with all the daughter boards in my possession including cedarbug (built) and the one before that with the LM4720 (forget the name). I built 4 daughter boards total (ex the ishikawa are w/o fets).
Edcor SUT are obviously included.
I am thinking 100 bucks for the lot.

I could sell the whole amp if interested but it would be more expensive and $$ shipping. The case itself is very heavy duty that can run the amp in the summer in FL. I posted pics in the M2x thread before.

Anyways, PM me if interested.

Letting my ACAmini go. Comes as pictured with wood frame and dongles.
SMPS included.
The amp is set and fully plug and play. No need to mess around with trimmers.

Usd 100+shipping.

Sold out now.


New, unused. Just received from legit distributor today.
Only 4 pieces available. The rest have been reserved by members here.

2 pieces for 88 USD shipped (registered + tracking)
4 pieces for 160 USD shipped (registered + tracking)

Paypal Friends & Family only please.

I've been a "Cedar Artist" as I refer to myself, for 14 years now. Specializing in Cedar art furniture primarily for Gatlinburg/Pigeon Forge TN cabin rentals and residential homes in the area too. (relative to the question and topic) and this time and experience has intertwined with my other hobby , since 1985, I've been an audio hobbyist and cabinet designer /builder. When I moved to TN and discovered the "regional specific" eastern red cedar, as it grows only in certain states, and while related to typical and more common western cedar, I've not truly found any specific studies compiled of data or results of anyone's experiments on the acoustics of the cedar as a whole, or in the "red heart wood inner wood" or using "only the white exterior pulp wood" as opposed, being that most everyone focuses on the red portion, of any cedar, leaving the softwood white out completely. The red in er heart wood has a harder, more crisp strength to it, but the white portion when properly dried, has a lighter "non sappy" appeal so much that I cut out my largest portions of it, and with some being over 8" to 12" by 6 feet, there is more than enough for me to do some trials.
Now, I am aware that many of you with build experience may or will say that no matter what, eastern or not, red or white, it's not acoustical wood for audio cabinets. And I humbly inquire the results of the tests you've collected, specifically on both and each, and the different things conducted in efforts to obtain best results. And if you haven't, please hear me out. Because I have recently conducted many, on both and each color, and with varying thickness and with/without assorted wood conditioners and resins for adding strength and resonance, for adding or taking the varied hardness of "limbknots" where for example, a cabinet side with several of them has an equivalency of many hardwoods density, and a side without any has a very different result. Good or not depending on your desired resonance and acoustical properties.
So, my new friends, I ask 1 thing before you pass any "too negative or dismissive objections" , that you please allow the possibility that with proper preparation, and specifics that I've given to the wide variety of testing, and conditioning, that it could very well be a " not better, not worse, but different" kind of very good, and highly acoustical advantage in acquiring specific and in general great sounding cabinets. If , like myself, the many people who desire, and in my case, truly enjoy the look of that "Wild-Fire" reds, oranges, tan, and whites of true eastern cedar boards when using the whole board of a cut tree. And even a cabinet with sides having solid white to red and back to white. Cured to a moisture content specific, with exact thickness tests and all. I know about birch, MDF and standard plywood. Who don't. But what if I gave you some samples, and see for yourself if you build, and if you don't, then at least let your ears hear a live , real demonstration not altered by phone or PC mics and speakers not allowing for the true quality to be known like you get with a live listening session. I'm not out to sell anything to you, other than sell the possibility that there may actually be someone out here that took the time most don't have to thoroughly test a multitude of samples of the wood in enough ways to definitively say, every reasonable way this wood can be tested to be absolutely sure if it's abilities or restrictions are known for any and all acoustic characteristics it can possess , is done. And I do welcome all builders and members comments, and just an idea, let's be nice, friends are always in short supply who are open and transparent with hard and long toiled hours spent to just give away the results , only to get heckled by "Yondoodle Pigglybuck" from whothcares Idaho when their knowledge of anything cabinet-wise comes from something like :Snoop Dogs book :"Yo Yo Yo You can bild-da-dopest car box! Vershizel!! , (and other projects while you burn a Doobie" )
Lol. But seriously, I've built 6 sets of cabinets, mainly for my customers who have a cabin full of cedar furniture and wanted their stereo cabinets to match. Naturally my very first few were a thin laminate of cedar overlaid on a nice but common cabinet as customer expected. But when I was asked to rebuild an entire acoustic piano, by removing it's wood from harp, and replacing every piece with cedar, so he would have the first ever eastern red cedar piano, at least to date, I've never seen one anywhere till mine. , but possibly could exist I got the notion to do my own cabs in the wood I live, but will only pursue " if" my tests prove it's a viable option if the sound came close or equal to a moderate to upper end (and possibly better) sound quality, even if I try out 1000 experiments and tests, plus, get the opinions of more audio enthusiasts.

This is where any of you come in to play, if interested and not to far away from Mooresburg TN, near Morristown TN, and Knoxville, Sevierville area, ect. My workshop/studio is open to anyone willing to stop by, and if you can't, I certainly would let anyone "borrow" a single small speaker "if" they want it shipped , they pay that cost, but absolutely not a sale, as there is no cost to you trying it out and fill out an opinion and idea letter and just mail the letter with ideas or opinion on it to me. After all, my ears hear one sound and yours may hear it better or not. But it's only YOUR opinions, the audiophiles, that can't best determine this. (My wife humms happily to a mono 4" old crackled speaker that is all the way left and the tone adjustment is her big " fine tuning the sound good like". Lol. So ya, great woman, lousy opinion on audio. She literally learned that speakers have " magnetic properties " when she got with me. So .. ya.. need anyone local and if interested and your not local, I'd love to send ya a free small example, now it's about the cabinets wood, so ill send a small cabinet, and you'd just need to put whatever drivers you have in it, and hopefully use only better drivers than cheap. Yes I do know drivers are matched to the cabinets, and it's a mated pair that's best, but, I can't send free cabinet AND drivers that obviously makes shipping heavier. And I'll provide the optimal range of driver specs to best test it. I AM NOT OUT AFTER Anyone's ADDRESSES ! P. O. Boxes, business address is fine, I am not a shyster, or whatever. Lol. God, after a post like this, if I were, sheesh, a bit overkill for a con man isn't it? I only want honest opinions and options for improvement "if" any. But I have a lot of confidence in its above the norm or expected level of results.
And if none are interested here, no problem, I'll still get my local opinions and let ya know the results. And when I can, I'll post pics of these beauties. Tha ja for your ear, your time, and hopefully, your "nice" responses. But there's always 1, (or5) in every bunch right? Lol
James B.

Is there anything like this out there? I'd like to turn an 18" sub into a powered sub without adding much weight. I already have an amp that meets the qualifications (CS800) but it weighs like 60 lbs or more and is huge. Would be nice to have something built in.

Rebuilding my Ekta Grande’s and ScanSpeak subwoofers didn’t satisfy my need to build something.

I’m really excited about the overall improvements in sound from the changes, and this build does not indicate unhappiness, but I really want to build a BIG speaker, just to say I did, if for no other reason.

Within reason, I’m not planning on cutting any expenses or time. I have ordered most of the crossover parts from Jantzen and the drivers (except for the super tweeters) from Lean in the UK. Drivers track delivery next Wednesday, no tracking yet from Jantzen.



Big drivers take a big cabinet. 42” x 26” x 18” (H x W x D), all 1” material, double milled Medex for the painted parts, Maple veneer/Baltic Birch for the others. Maple hardwood frame, plenty of bracing.

After the fun and success of the new Hypex Fusion FA501 plate amp for my subs I’ll be using the FA502’s here. One channel for the MTT and the other for the 18”. There will be 4 sets of binding posts so I can use jumpers to choose full Active, partial Active, bi-amp from outside source, single outside amp. Versatile.

Been scribbling notes all day to give to my CNC friend to input and cut stuff up. All good fun.

Cabinet design will be somewhat simple, going for elegant, understated, and not a copy of anything I’ve seen before. For sure nothing that looks like a transformer that may come alive and come get me in the night!

I made an outline/template and have had laying on the floor for a couple days to get a feel for the size. My wife told me to go for it, so one hurdle out of the way!

Hi,

I am using an relatively high power exciter (electromagnetic speaker driving a plastic plate instead of a cone) of Visaton, my application is to transfer sound tones to a solid. But its size is big and I want to find alternative to reduce the size.
Is there any planar exciter to purchase or can be built?
The MEMS speaker or piezoelectric transducer is small, is it possible to couple its sound to solid?
or other?

Thanks!

Danny

[SOLVED]
Hello everyone..I am new to the forum. I have a problem with NAD 3150 amplifier to which all capacitors Pre and Main sections were replaced, because the originals were now in bad condition; new ones are Nichicon, Panasonic, Elna. Replaced transistors Q609-610, Q619-620, Q621. Also replaced the VR601-2-3-4 trimmers. Following the NAD service manual, I make the DC offset adjustment without any problems; I then switch to BIAS..I start with VR603 and stop at 5 mV stable, then move on to VR604..but as soon as I get to 2.2/2.4 mV a "jump" happens towards 30-40 mV and beyond, and the left channel power amps Q615-617 warm up; so I turn off and start again, but the same thing happens again. I then attempt to start with VR604..which this time gets settled steadily to 5 mV, without "jumps"; I then go to VR603 and it happens that it now jumps exactly as VR604 did before, and it heats up the right channel power amps Q616-618. In practice, the situation is mirrored, with "swapping" of settings-voltages. The power supply on the two channels is perfectly balanced, according to the voltages in the schematic. Balance at center, Bridging OFF, speakers impedance Normal. I have only a NIMEX NI8400 digital multimeter autorange.
Any suggestions? I thank in advance those who can help me.

Oh boy. I actually started the initial Iron Pre a year ago and built as I was able. Took forever. THEN, I got an offer that I couldn't refuse, and I didn't. Will be building a second unit for myself.
Let me state the following: I am the kind of builder that isn't happy until something is built beyond expectations in durability. For example the chassis is good to start with, but I added a brace for the top where there are no supports. This is a typical design for most any chassis, but no not good enough for me. I don't want any flex, rattle or any kind of mechanical noise when you thump on the top sides and underwear. heh heh. Just the way that I am. Next off, I didn't like the plastic switch used for the selector, because I really don't like plastic. So now you get a stainless steel $60 switch made by Elna. I don't like cheap jacks, so all of the jacks are Manley. And on it goes
FWIW, I only put in 4 inputs. Three on the back, and a little input jack on the front. This unit not only has two outputs, but a pass through RCA set just so you can hook up directly to a headphone amp without going through all of that unneeded circuitry and volume control. Even put a metal cover the tranny because I think that although it isn't needed it looks better.
So if anyone might be interested, this will be sold for the cost of parts. Ain't that cool? $800 takes it.

Anyone got a schem for this critter - the one on my bench "has issues". Also need generic numbers for the house numbered output devices (484081 and 484002)
cheers
Mike

Hello
I need help from some Sweden user with Blocket.se account to get in contact with an user.
I'm based in Spain and cannot connect to blocket.se

Best.

I have a crate gt 80. The volume keeps cutting in and out. I have replaced the main input Jack cleaned the pots really good and replaced two Zener diodes IN5353B and the problem still exists. From what I have read up on these amps this is a common problem. It occurs on both solid state and tube settings. I have read that putting a cable from line in and line out on the back of the amp fixes the problem. So far I have tried that and it seems to work well. Does anybody know what part needs to be replaced that would cause the amp to cut in and out. Thanks. Mike

I’m looking for a small drill press. Something not too expensive but accurate. Plan to use it for drilling heatsinks. Websites?
Thanks

Some time ago I acquired a set of old Audiostatic ESL’s. They are (of course) not in good working order so I probably will rebuild them, I've rebuild Audiostatics before so that will not be any problem.

But what wonders me is that this is a model that I have never seen before, nor can I find any references to the model on the web or elsewhere. The faceplate on the back says it's an ES200, but the construction does not look at all like the common ES200R/RS models that I know of. I think it predates the familiair ES100/200/300 series. I disassembled them and construction of the internal ESL element itself is very similar to an ES200 panel, but it looks like it was mostly hand built without jigs or so. White stator wires instead of the usual black ones, the aluminium crossmembers that hold the wires are very uneven spaced and some are even not glued on straight. The frame is unpainted MDF covered in cloth, it stands on two oak stands and is tilted backwards. The interface does have a mirror drive and two audio transformers that look identical to the ones used in the later models, but the input circuit is different, with just a 47uF MKT cap for the mirror drive and not the usual additional RC network.

I would be interested to learn more about this model, so if anyone can shed a light please let me know! So far I draw a blank everywhere I asked.

Just in case any members are interested...
https://www.ebay.co.uk/itm/134896748673

I saw a pair of DQ-10s on e-bay, and got a flashback.
I was a kid when I walked in a proper hi-fi store of the late 70s, and I asked the kind salesman if I could just listen for 10 mins to those great machines that they had on their window.
He smiled and switched some speakers driven by a walnut framed black and silver, floating turntable, connected to a small control unit with right and left volume controls and a hefty black amp. Wow! All was so nice, and then he switched to a weird pair of non box-like, curvy ones, with white grills and oak cheeks.
Those sounded so much more free than the others! They breathed somehow. I still recollect that moment.
Then I started collecting magazines and those things wore actually a Linn LP12, a DNM pre amp, and a powerful Mark Levinson amp, driving Infinity Kappa towers, Linn Isobariks, and Dahlquist DQ-10s in white gown.
Never saw them again since, not even as vintage in someone's hands. They must have not been really distributed in Greece back then. Maybe members of a small import of 'exotic' American models of that era.
Some American forum members must have lived with them or had many listens. Did they really work well? Was there any real science behind that ''phased array'' concept and 5(?) way crossover? Is anybody familiar about their acoustics idea of panels with drivers everywhere behind a grill?
Was that the best speaker in the room, or I just was so little and it was white and curvy?

Here is it with classic black grilles and many photos from one
ebay auction

Hi All,

I'm doing development of my new push pull class A EL34 amp. I am currently working on the design of the input part. (Pic_1). +HT is 440V from regulated supply, 30 seconds delayed after heating. Operating point you can see on pic_2.
My question: is 440V HT safety for E88CC?
When i look in datasheet there is two maximum Va values (Pic_3). First and second row.
Which is important for me? I always thought that Vao is the value at start-up, or the value when Ia=0. Then what is the second row in the datasheet for?

Thank you

Jan

For sale, new semiconductors as listed below. Quitting the hobby. All purchased by me for various unfinished audio projects. Most were purchased from reputable vendors such as Mouser, Digikey, Newark or RS.

$150 $75 AUD for the lot plus shipping from Australia.

NB: Shipping internationally from Australia is surprisingly costly. Not sure it will be cost effective for overseas purchasers - especially if you're trying to cherry pick a few items.

I can accept payment via EFT or Paypal Friends & Family only.

Have a set of Kef X300A of which one has become noisy. Replaced the capacitors in the power supply, seemed to solve it, but the static noise came back overnight. Have included a clip of the noise recording, I believe this indicates a faulty transistor?

I have now removed the AB amplifier from the speaker and found many transistors on the board. It’s a two channel amplifier that bi-amps the Kef coaxial driver.

The board consists of:
2x 2SC5200/2SA1943
2x 2SC3421
2x 2SA1930/2SC5171
2x 2SC2229
4x 2SA949

It would be quite cost and time intensive to replace them all. Is there a way to go about this?

Clip of the noise:
Login to view embedded media

I know there were some high frequency issues with the older 1628SE transformers made years ago that tainted their reputation, but how are these newer 1628SEA units, specifically for use with a KT88 UL SE amp? TIA for any first hand experiences good or bad.

WTB Looking for 2 902 hf loading caps and rear covers. Will buy any other rear covers that fit.

This driver was featured in Voice Coil this month. One of the best compression drivers I've seen measured and the best 3" diaphram driver meaurements I've seen. Less than .5% THD in the 1-10k test band @ 104db/1m. Clean waterfall plots all the way through the upper octave. Extension out to 20k. 112db sensitivity.

I'd like to see higher spl measurements but it's better than anything else measured in the last 6 years I've seen in Voice Coil. It looks like it might be a real winner for very low compromise high efficiency systems.

http://www.18sound.it/Products/Articles/Detail/catid/4062/eid/5008/nd3st

I built this preamp:

and I'm planning on attaching it to this amp circuit via terminal connectors: to drive a Jensen 25-watt 8-ohm speake. Currently there seem to be issues with the simulations as you can see:
This is being fed 0.2 Vpk. If the input for the current design exceeds 0.2 Vpk it distorts. The preamp is outputting 2.3 Vpk which is way too high. I'm having trouble figuring out exactly what the solution could be?

https://www.cnn.com/2024/03/11/business/vinyl-records-uk-inflation-basket/index.html

Quote: "The prices of vinyl records will feed into UK inflation statistics for the first time since 1992, highlighting a surge in their popularity among British consumers driven in part by Taylor Swift.
LPs — which dropped out of the UK inflation basket more than three decades ago, owing to the rise of CDs and cassettes — have made a huge comeback in recent years."

Which one is 'now so hot' ?............ Vinyl or Taylor Swift ?

Fern & Roby, whose standmounted Raven has attracted lots of interest, now has a floorstanding version with a baffle board of .75-in black solid Richlite.

https://www.fernandroby.com/blog/2021/raven-iii-assembly-process

Beautiful woodwork!

john

Hello, I have a kinda stupid question about powering my upcoming bluetooth speaker project. I decided to go with ICEpower 200ASC 200W amplifier board. The problem is that I will also need to power a DAC board and ESP32 for bluetooth connectivity. The 200ASC has 230 VAC input but I need DC voltage for the other components. Can I connect a switching power supply and the amplifier in parallel from the wall outlet? (I deeply apologize for my diagram, it's only for explanation purposes and it does not have ground wire). Thank you so much for help.

I have a box with two TPA3255 amp modules in it (I don't think it actually matters what kind of amps they are, but oh well). A single 48 VDC single rail SMPS powers both of them.

Right now, the power inlet module has its ground tab connected directly to a chassis grounding bolt very, very securely. I also have a ground loop breaker, with its safety ground connection made also very securely to chassis. Its HRG (high-resistance ground) side is tied to the 0 VDC output of the SMPS.

My SMPS has, on its mains input side, L-N-G/E. My question is, assuming I want to minimize any ground loop issues if using single-ended interconnects, do I want to attach G to chassis safety ground, or to HRG, or not connected at all? Keeping in mind the 0 VDC is tied to HRG and the chassis is very well connected to safety earth.

I believe, but am not certain, that SMPS inlet G is not tied directly to ("common with") its 0 VDC output. I don't know what, if any, capacitors are placed between input & output sides.

Peace and good health to all, and thanks in advance.

ive actually abandoned this psu circuit for my preamp in favor of a bridge rectifier/voltage double circuit after messing it up. But id like to figure out how to fix the circuit so i can learn something.

attached is a schematic of the psu circuit i was using.
While tinkering the -28v broke lose from the board and i didnt notice. It was touching the positive heater coil wire for the first pin when i turned on the amp, and it mustve created an arc. It soldered itself to the pin. And i def didnt do that.

It was on long enough to totally fry R9 til arc, snd it straight up melted Tr4, it killed Tr3.

I replaced r9, and both transistors, and the PSU is working again with stable voltage output, it powered the preamp just fine and sounded fantastic, HOWEVER, there is now a dull hum that stays the same volume no matter where i put the volume knob on the preamp. It sounds like 60hz, but im getting it out of my mid bass drivers too, which xover at 120hz. So it may be both 60 and 120 together im not sure.

im a total novice, so at that point i just built a bridge rectifier and voltage double to power the preamp from a single transformer that outputs both 12v and 26v

If anyone feels like helping me figure out how to diagnose what's wrong, id love to fix the initial PSU so i learn something about what happened. Thinking maybe i damaged a diode and its leaky now? idk

Amplifier section schematic too, but i dont think its totally necessary. But not sure so posting it too anyway

I dont think i really like the original PSU design, seems quite complicated for the result it gives, but it ran much cooler then my current one, and performed identically, and once c2-8 were all swapped with 2200 uf it was DEAD silent until the fireworks lol

Edit:: I did experiment with adding extra filtering caps, nealy 10,000uf no change. Other unused sets of tubes, no change. Gotta be the psu circuit right? I shoved a lot of current through that negative rail pretty sure.

Good morning. So this is a personal apology from me to Mark That he has no idea about. I didn’t bash him on the forums or bully him when he was part of the forums at one time but, Felt bad for him. So with that out of the way here goes. I was excited to get the new drivers from Mark Audio called the Alapir 6P. A 3” inch paper full range driver with a blue cone. I got them and I tested them and didn’t like them to be honest. I traded them with a former friend of mine. I was a Fostex Camp driver man. So years past and I did buy some other mark Audio drivers but, never used them and an acquaintance of mine wanted them So I traded for a nice pair of speakers and that was that. Fast forward when the Mark Audio CHN-50’s Came out and I watched Marks video on you tube about these drivers the design behind them. I bought a pair and made a rear ported box. I turned them on at low volume and they sounded so opposite of my Fostex speakers. I thought maybe something was wrong with them. No they are that neutral everything plays like it should and nothing sticking out with music or bright sounding. Fast forward again years later and am still enjoying the CHN-50’s and now I just bought a new pair of the CHN-P50’s I got for my next Project. So to sum this apology letter up to Mark Audio: I’m Sorry I Judged your metal cone drivers (I was bias, of Metal cones) because of what I have experienced in past times of them being super bright and not easy to listen to. Am Sorry for not giving your speaker drivers a chance to break in and listen to them. Thank you for continuing advancement in your driver’s technology and development. So The CHN-50’s are my go to driver now for best bang for your buck performance. Mark you are one of the most gifted Full range driver Manufacturers and designer and developer in the world. Thanks for all you do for us Diyer’s Mark. The reason am posting this on the forum is maybe someone is still in touch with Mark. I have sent a few e mails and I have heard nothing back. Mark I hope your well and happy and blessed. A buyer and friend for life. Sincerely Jeff.

Hello all. I lost one of the transformers in my trusty and somewhat sacred Citation 16. Mine is a A model, but to the best of my knowledge they are all the same across the model line. If anyone has one lying around I'd much appreciate working something out. Physical space limitation precludes use of modern toroidal style. Thank you in advance.

I have an old 2 channel lafayette reciever and want to build a little 8 inch sub for it. My question is, can I build an external crossover for each channel that will route the low end (100hz and below etc.) to the sub and then send the rest on to the bookshelf speaker? Or am I going to run into problems with impedance and SPL and all manner of other things?

Hi,

Recently I have made a comparison of several mid ranges I have had been testing.
Test setup consisted of Dayton EMM-6 condenser microphone. Distance to driver was 35 centimeters. Drivers mounted in boxes between 2-5 lliters each. Measurement level was 2.8V which equals to about 90-92 dB. A small chamber was made by using a blanket while attempting to reduce interaction with the room. Contenders :

1) Scan speak 10F/8424G00
2) Peerless fsl-0512r01-08
3) SB Acoustics sb12mnrx2-25-4

As it can be seen F10 and fsl-0512r01-08 are in a similar ball park. F10 looks to have very good distortion figures, while, suprisingly, FSL-0512r01 burst decay looks somewhat better.
At the end of the line follows SB acustics SB12mnrx2-25-4, showing significantly more distortions.

Regards,
Lukas.

I am planning to build a couple of speakers (a bookshelf set, and then a floorstanding set) using 3/4" baltic birch ply and a hardwood front baffle. I have some 1" thick dense hardwood (ash? White oak? Cant tell which) in my garage, cut about a year ago on a bandsaw sawmill.

I was planning to just glue the hardwood baffle to a backer ply board using Titebond.

However, I found this thread on another forum when I googled. https://techtalk.parts-express.com/...1444871-solid-wood-baffles-with-mdf-ply-boxes

Is it bad to use the glue route? And I should instead float the hardwood front baffle on top of the birch ply with a thin gasket in between?

Hi guys! As i almost finished my sistem,im now experimenting with diferent type diy interconect cables. I try diferent copper versions,tick wire,thin wire,mesh shielded,aluminium foil shielded,full wire,many thin wires,quad star construction,spiral construction,etc. Now i make 2 version from silver plated copper 1mm thick full wire. Thats for now the most detaild and open,clear sounding one. Im waiting now for second order of silver plated copper wire,this time 0.2mm,0.3mm,0.4mm and 1mm.
I read that thiner=better for interconnect.
I also read that foil based cables sound the best.
So its very interestig research for me. Im planing to make and test many more,just to play and to get the best from my sistem. So i was thinking its maybe good idea to make thread so we can share expirience and good recepy. For long time i was thinking that cable dont have big importance in sistem,and that can not efect so much on the sound,but now with TH100 SA monoblocks and Dallas II speakers,the diference is more the ovious.
So anyone who have some good expirience with some diy cable,fell free to share recepie for all other willing of good and detailed sound.
In research like this,its not posible not to find many good words about "The supercable cookbook" but i cant find it anywhere. From tube state its impossible to order.
Have any one copy willing to share?

My next project is thin silverlated copper interconnects. I will post resultats and photos.
And here is few photos from cables made and tested.

I'll start a new topic on modifying a finished amplifier.
I have an assembled version of the amplifier, which I have already modified, so this will be the second change in the circuit.
* the circuit is very simple, there are no current sources in it, initially there was no correction at all, the sound in tests is below average.
Changes were made in compensation, and some modes of the cascades were changed, it began to play much brighter and livelier, but I still think that from such an array of parts using a symmetrical topology, you can make a more practical simple amplifier with high-quality sound.
in the attachment

• initial diagram on a piece of paper
• photo of finished boards and cooling radiator blocks
• My power supply is standard +/-36 volts
• 
  
• further attached is a version of the scheme for modification, it includes the following:
• 2 pairs of differential cascades in symmetrical topology
• frequency compensation capacitor C5 (4.7pF) covers two amplification stages
• two-stage output stage
• dual output power transistors
• transistor modes were selected according to the minimal "soft" spectrum of distortion
• at a frequency of 1 kHz with an amplitude input voltage of 2 volts, distortion is less than 0.003%, at a frequency of 20 kHz - 0.03%
• slew rate 55V/µs
• output power 100 watts 4 ohms
• pole 300Hz
• open loop gain at 1kHz - 88dB (in the version on the leaflet, the open loop gain at a frequency of 1 kHz is approximately 64 dB)
• openloop unity gain frequency 3.8 MHz

Attached is a diagram into which this block will be converted.

At Mytek Audio in New York we have an roll of a brand new sealed 2000pcs of CSR8675C-IBBH-R purchased from Future Electronics we never used for production.

Looking for a buyer who may need them at good price. Please reach out if interested via email or phone to New York office : https://mytek.audio/contact

I have two KH 2.2’s. I am interested in building my own subwoofer to go with them, but I’m not sure what the best option would be. This would be for listening to records, streaming music, and playing around with my mixer.

Thank you for any advice you guys can offer!

I have boards for openamp1, ...I have 4 pcs left if anyone would like.

Openamp1 thread

10eur + shipping

I have for free 20 M2x unpopulated daughter cards as seen here. First Watt M2x
Four Austins
Four Tucsons
Four Ishikawas
Four MountainViews
Four Norwoods

I will never use them so you can have them for the cost of postage.
However, if you'd like to return my act of kindness I believe I'm short
some IPS#7 boards.

Regards,
Dan

I see that in some of Trols' speaker designs, he lines the port with felt. I assume this creates an aperiodic port? Acts somewhere between the size of the original port and the new stuffed port?

I tried it on my 2-way floorstanding speakers, and I liked the result more than fully plugged ports (I rely on my sub for the really low stuff.