SOLD

Asking $75, including US shipping.

I am selling this SLB Power supply board, as I am not going to build the amp it was intended for.

Parts were sourced per the V1.2 BOM, so it should be able to be used within the parameters discussed by XRK971 in the thread

https://www.diyaudio.com/community/...ct-crc-cap-mx-class-a-power-supply-gb.336479/

The large BJTs are on flying leads to a small heat sink that can be mounted to a board or subassembly.

Three additional chips are also provided in this sale, maybe you could use them in another build or keep as spares.

1) BD140

1) TTA1943Q

1) TTC5200Q

These power supplies have performed well in other amps for me and provide a very quiet supply.

I will ship via USPS.

I am experimenting with an extended bass shelf speaker idea. it will be a wide face and shallow depth box flat againts the wall (and surely i can fill it up with stuff to make it smaller). im going with a 12L box because some other drivers i am playing will fit this box well and i have some spare wood.

is 12L tuned to 45Hz to big and low? i am trying to exploit room gain and a large baffle and positioned near the wall to bring the shelf up 2dB.
i know this is not ideal, looking to build a fun not accurate speaker. or will going this far make the lower end less pronounced?
Green line Vb=12L Fb=45Hz F6=38hz
Pink line Vb=10L Fb=55hz F6=46Hz
normally i saw this driver in 7L boxes.
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10L and 7L with Fb55hz have basically the same F6. so might aswell save on wood and use a 7L, but the 12L is still interesting with a flat bass shelf that plays -2dB less but almost 10Hz lower.
anyways, it is a wacky idea with cheap drivers. what are your predictions?

Hello,

I have a Kt88 tube amplifier that I ran some tests on with The Stuff Made audio analyzer suite. In the THD Test after it hits 10k hz the distortion drops like a cliff. I dont have a whole lot of experience testing amplifiers and would like to know if anyone can tell me if this is normal. I attached a screenshot.

Thanks

I've had this $60 Chinese "Breeze Audio" DAC with ES9038Q2M + XMOS XU208, in my parts bin for a few years.
https://www.aliexpress.us/item/2251832769021342.html
https://i.postimg.cc/JhXCRD8N/s-l1600.jpg
https://i.postimg.cc/BJsLwTpZ/s-l1600.jpg

Looks similar to Topping d10, and the Breeze might have potential for DIY.
Maybe short those output coupling caps for starters?

Anyone know where I could purchase a sheet or two?

I need help with a diagram or part number for ic3 on my taramps bass 8k please. Mine was so burnt it crumbled and can't read any info to look it up. Any help would be appreciated...

I have a taramps bass 8k and my ic3 smoked and I can't read anything on it ... if anyone knows what the part number is so i can order from mouser I would greatly appreciate it ... I tried looking thru photos of the board but nothings legible ... thanks in advance

Hello all,

First post here. I have an old 1950's Stancor A-8101 5W universal line to voice coil transformer. I'm using it to couple household 120v AC mains to the output of an old Eico 377 audio sine wave generator that I believe uses 6K6 output tubes. Some old school clocks I'm working on require a high frequency signal sent over the AC line to engage the correction mechanism. This setup working perfectly, but the Stancor transformer is in fairly poor physical shape.

I'd like to replace it with a modern equivalent if possible. The Stancor catalog lists it as a 500 ohm primary side and either 3.2 ohm lug or 6-8 ohm lug on the secondary side. AC mains is hooked to secondary COM lug and 6-8ohm lug. I'm not very knowledgeable in this area, and researching hasn't really dug up a modern 500 ohm to either 6 ohm or 8 ohm one, much less one with a single 6-8 ohm secondary lug. Can I substitute a more common 600 ohm to 8 ohm transformer or is there a special reason why the Stancor transformer had a secondary range value 6-8 ohms instead of either 6 ohm or 8 ohm?

I have a few Bogen PA system 70v transformers, but was hesitant to try them and fry something. Basically, am I stuck with using old output transformers made over half a century ago?

Thanks,
Ian

Hi diy'ers, want some recommends I've previously asked perhaps in the wrong forum section, about the Hypex UcD700HG/HxR with an existing linear power supply and a custom made control/protection board.

However my main concern now is the protection trigger circuit, this has to be triggered if the UcD module pull to low the pin-10, but looking carefully the pdf datasheet of both modules, the UcD700 seems to have a 47k resistor in between while the UcD2k just directly pull to ground pin-10 without any resistor apparently, and the simple protection circuit I've designed need at least ~2mA to trigger the optocoupler reliably.

Unfortunately the closest optocoupler I've simulated on LTspice was the PC817A, but I have no way to simulate the SFH617A-4 since is not in the component list of the latest LTspice, also the SFH617A-4 will be feed with +24v through a 10k resistor and tested ok on the bench, however I can't activate it through a 47k resistor.

Hope some experienced users with the UcD700HG and the UcD2k can confirm this, so I can design a more sensitive/discrete trigger protection circuit or just find some PC817A replacement before ordering the PCB's.

Here is the DC-Error/Protection circuit of the Hypex modules:
UcD700HG:


UcD2k:


Also re-post the project in question images for reference:

Regards!

Hi

DCX 464 are sold but ,

the B&C ME464 horns are sold

I am still selling a pair of crossovers $150 for both .
the crossovers were built with better parts by madisound with the published schematics from B&C .
crossovers are unused .

paypal adds fees . shipping within conus included

I got this to make it work for a friend.The Off and left right switches were not working,cleaned and made them straight...then lubed the platter bearing with compressor oil .Tomorrow some white lithium grease and fine silicon oil will find its way to the tonearm sliding mechanism, all grease and oils being brought to me by a very good friend @sergiu2009 .
It came without the cartridge and having one unused I got the full refurbishment job.
Some minor problems need to be chequed.
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As the title says - In an underhung motor design where the voice coil is entirely within the magnetic 'air' gap, do shorting / faraday / demodulation rings have any impact?

I scavenged samsung passive 3ohm 170watt subwoofer.
I want to use it with my desktop PC speakers, if I can power it without buying equipment


Can I use a 2.1ch 4ohm as if I only use the subwoofer channel & keep the volume <50%?

Or use a lower voltage psu on the amp, or a series resistor ?

Hello beautiful people! May the 2023 be the best year for you all! I am looking (preferably from Europe) one of the following power amps to get :
-Onkyo grand integra M-510.
-Accuphase P-360.
-Accuphase P-500.
-Accuphase P-500l.
Please PM me for anything 🙂
thanks a lot!
George.

Both in real live and according usual flow charts in the service manuals spindle motor starts just after 3-times up-down procedure of laser lens and follow sending FOK signal.
Now I have a device (model CDX 730E) on the desk with an issue mentioned in the head line (without TOC reading, of course - up-down procedure and laser light in this period of time is present).
This problem appeared suddenly.
This behavior is identical also without insert compact disc.
Such behavior I haven't observe until now. Changing of laser unit (KSS-150A/KSS-210A and even completely mechanism (SONY KSL-210AFM/KSL-2102AAM) don't provide any change - this means, both the disc motor (brushed version from Mabuchi) and the laser-unit are responsible for this behavior.

How should I start the trouble shooting procedure ?
Thanks for comments.

This threads don't provide the wanted information:
https://www.diyaudio.com/community/threads/yamaha-cdx-1100-spindle-motor-driver-problem.288084/
https://www.diyaudio.com/community/threads/problems-with-yamaha-cdx-1100.154872/

Thought of starting a thread about getting a good sound in relation to the price.
Here you can perform any drivers. Cheap or expensive that you think works well in the box construction you have chosen.
Extra fun if you've created something that doesn't cost much.
Feel free to make a list of drivers that you think will be good in relation to the price.
Drivers on a budget.

Hallo everyone,
I search a long time a data sheet ore book collection from optical pick up's especially from Sony (widest type range).
Only from Samsung I have found complete datas online - see
CDP Traverse Deck Model CMS-B35BG6 (Samsung Laser-Unit SOH-AAV) Part-No CDM31279
http://www.haluyatech.com/down/sgnec/CMS-B35BG6-20040303.pdf
CDP Traverse Deck Model CMS-B33SG6 (Samsung Laser-Unit SOH-AAX)
http://www.haluyatech.com/down/sgnec/CMS-B33SG6(20030210).pdf
Please let me know more about such data books from all KSS types.
Thank you very much,
Best regards
Andreas Kirschner

I have for sale 2 Hammond 193T chokes (50 mH/2A DC). I purchased these from another DIYAudio member for a MoFo amp but don't need them any longer. I believe they are unused. These are currently selling for $49 each on Mouser, so how about $49 for both of them, plus actual shipping (should fit in a flat rate box).

Can we use this thread to post information about how to mount DHT tubes horizontally?

A lot of them have orientation restrictions. I've been doing a search and found this so far.

"Directly Heated Rectifiers
The type 80 rectifier, vertical is preferred, but if mounted horizontally, pins 1 and 4 must be either at the top or at the bottom. 5Y3 vertical is preferred, but if mounted horizontally, pins 2 and 8 must be in a horizontal plane. Most modern data sheets do not list the orientation restrictions. Franks tube data pages have lots of old data sheets, mixed in with the new data sheets."

I don't know if this applies to other directly heated rectifiers.

I particularly want to know about 2P29L, if anyone has experience or details. But other common DHTs too like 2a3, 6B4G, 300b, 10Y, 26, 4P1L etc.

XLO Pro 600 Speaker Cable (2 pairs which makes it double Bi-wire)

1 Pair is terminated with ETI Research Copper Spades at both ends. Length is 2.5 meters.
1 Pair is terminated with Mundorf BFA Beryllium Copper banana at both ends. Length is 2.5 meters.

XLO Pro 600 is an 11 gauge cable using 99.994% pure OFHC conductors. Each side is composed of multiple individually wrapped conductors that XLO calls a "Litz-variant" geometry.

This is a balanced cable with both excellent bass and smooth treble. Definitely a great value for the money, hardly any speaker cable that can beats it near its price.
Very good detail, no harshness or glare, and doesn't seem to add much of its own sound to the mix.

I purchased Both pairs used from UK in 2019 and impressed by this cable from day one, selling now because upgraded to Audioquest speaker cable.

Selling Both pair at very reasonable price of $240 including PayPal fee 5.5%.

Used price worldwide is around $125 for 1 pair 2.5 meter length.

Shipping to Worldwide at buyer's risk, but it will packed carefully.
Please contact me for shipping charges to your location.
Shipping to world will be through INDIA post Registered mail which will take 2-4 weeks.

Thanks for looking.

I acquired a big lot of Sylvania 12AU7 A8V tubes with date codes 57 05 22 and 68 12 42. The former is a short gray ladder plate, latter is long gray ladder plate. Both are green logo in block letters. I have Googled and come up empty on these particular tubes.

I've been noodling around with HornResponse and have put together a 40hz tapped horn sub that is a single sheet design. Before I start cutting wood, I'd love to get feedback any of you might have. I mostly just want to make sure I'm not overlooking anything huge.

The main design goals:
1. flat from 40hz to 110hz
2. good sensitivity, 95+ db - I'd like to be able to use in a semi portable set up using batteries and solar panels
3. low overall weight - light enough to carry by one person
4. small footprint (but tall is ok)
5. one sheet if possible
6. ok appearance for home use, but loud enough for small PA.

The driver I ended up with is the Kappalite 3012lf. The xmax will limit it to around 120db at 33v (I plan to use a smaller class D amp). I will build it out of 1/2" (12mm) plywood. The back panel will be made by scarfing two of the pieces together and then bent using kerfing. The weight estimate is around 50 lbs (22kg).

Attached here are several screencaps from HornResponse and a Rhino model along with the one sheet cut.

Thanks for your thoughts.

Hey all,

Recently a guy gave me a couple old home-built speakers that I scrapped out for parts.

The passive crossovers were made by Peavey (and mis-matched), and I can't seem to find the specs on them.

I'm not sure how to describe them, as they seem to be some sort of 1st order-Low / 2nd order-High (??).

PV# 70501558, C1=2.0uF, L1=0.363mH, L2=0.60mH
PV# 30501592, C1=1.5uF, L1=0.342mH, L2=0.738mH

Can anybody decipher the xover freq's on these?



Regards,
JohnR

A speaker cover, also called a speaker grille, is always applied in the home, automotive and professional audio industries. It is used to protect the driver element and speaker internals from extraneous items while enabling sound to pass through clearly.

Does Speaker Cover Affect The Sound Quality?
This is a common question that people would ask. There are a variety of speaker designs in the market, with or without speaker covers. Hence, there is no absolute answer.

Sound waves are longitudinal where the particles travel parallelly. The speaker grille must interact with the sounds when it is sitting in the direct path of the driver. As a result, a reasonable compromise between protection and sound quality must be considered based on the use of speakers.

In fact, an appropriate balance of protection and sound quality can be achieved by taking careful thought throughout the design and manufacturing processes. Hence, it is critical to seek a professional speaker griller provider in order to enjoy the best sound quality while providing sufficient protection for the speakers.

If you would like to know more about speaker covers, visit our site: Grille Tech, speaker manufacturer in Malaysia

Ex Tektronix 500 series scope ceramic wafers, will need leads etc de-soldering - £12 + £3 postage in UK. See pic.

Drop me a PM if interested, Andy.

Is it recommended to use NP caps in xovers which ask for big value caps in the woofer section?
1. What about the sound quality as compared to MKP or other usual Caps used?
2. If they blow (being small in size) is there a risk that the driver speakers blow simultaneously?
I will need to use 68uF in series with the woofer and 82-100uF for the mid. Any advice an example of such cap can be viewed as attachment.

Hi
Anyone here have knowledge or experience with Ferrofluid used in dome Tweeters from either
Dynaudio or Morel?
Specifically, the exact type used in these tweeters (& who sells it) and whether it needs replacement after 20 years or so?

Thanks

Greetings Fellow tube heads,

I just found a pair of Mullard branded EL 37 tubes and wondered if they could be substituted in place of EL34s. I have a Boyuu A9 SE UL amplifier which I built from a kit. Has anyone tried this? Why not try them and see for yourself I hear you ask? Because I want to check they are ok on a tube tester first.

I would very much appreciate any opinions about these tubes. I've just noticed there are some threads about this tube so please excuse my repeating the query

Kind regards

I did a search of the forum but this didn't seem to be addressed specifically.


That's not my audiogram. Just an example. But for those of us over 60 I wonder how often it has been the case that a crossover designer has, for a speaker design intended for 95 percent personal use, tuned the frequency response to compensate for a professionally measured audiogram.

Good evening (here) to all,

I’have two GFA 535ii’s, bi-amplificating my Tannoy’s. They are both perfectly working in terms of audio output quality but only one of them has a problem that I could not solve in any way.

The Power supply transformers of this one are audibly vibrating. There is no additional hum in the audio output signal but the chassis acts as a resonance box and when there is no sound in the room I distincly perceive its 50 Hz noise.

All electric parameters seems to be ok. The current absorbtion (signal inputs shorted) is the same, 360 mA, for both amplifier. The Transformers output Vac and the power supply board output Vdc are in line with the service manual. The Bias s ok for value and stability.

I tried removing the external metal (mu metal ?) band of the transformers with a little improvement. I placed a foam layer between transformers’ bodies and the chassis but this amplifier remains noticeably noisier than the other.

Has some of You solved a similar case ? I suspect that its transformer have been slightly damaged in the past (i bought them second hand).

Can someone give some advice ? Could someone, in case, supply me with couple of ‘new’ Adcom 535 Mk2 transformers ?

Thanks in advance to all for any help.

Selling two matched K75 250V capacitors, quite heavy and big in size, they measure 9.92uf and 9.70uf
Never used and in perfect condition. 18 euros the pair.
Paypal for friends. Located in Europe

Hi!
I have two old NAD amplifiers, a NAD 319 and a NAD 3100, each with their own problems..

NAD 319
This amp has had issues for a while. When in use, a humming sound starts building up and eventually becomes louder than the music playing. The noise' volume is independent of the volume of the music. I have more or less ignored this issue (deadly sin..?). The noise disappears if I slide an RCA cable across the inputs (so basically connecting their grounds together?), and recently I grounded the chassis to wall ground, which also seems to resolve the issue.. But I am sure this is not a very good solution..

Recently, another issue has appeared. If playing at low volumes, one or both speakers will either cut out completely, or at least start crackling at a very low volume.


NAD 3100
This amp never had problems before, so I figured I would use it as a replacement for the 319 until I potentially could fix it. However, this one also has developed some problems. When switching on, either none of the speakers work, both speakers work, one or both speakers might play at a very low volume, or a combination of these. It seems completely random which speaker works or not. By pressing the speakers A/B button in and out a bunch of times, I can eventually get to a state where both speakers play normally, but I would rather not have to spend 5 minutes repeatedly pressing a button..


Does anyone have an idea what might be the cause of these issues and what might be done to fix them? I also do not currently have an oscilloscope or a signal generator, only a multimeter and a soldering iron, so I am limited on what I can do. I am sure there are more details I should give, so just ask away. Thanks in advance for any help, and I hope my temporary fixes doesn't hurt you too much 🙂

As my old little mixer unit died and I had to settle for a $50- replacement I just picked up a cheap Behringer Ultragraph just in case I need to do any modification of the sound or I need to hump up the bass a bit.
I have assumed it went in series between the mixer and the DCX crossover but before I go out and buy some more patch cables I thought I should double check the flow sequence.
Not wanting to blow anything up etc:
I didn't know it had a mono sub output but I won't be using that feature at the moment

I am building a small (small as I can make it) board for Balanced-to-Unbalanced (and vice-versa) conversion. Everything fits so far as I used 22uF 4mm electrolytic bypass capacitors on the incoming rails. I usually see 47uF caps used for this purpose, but those are 5mm caps. I would have to enlarge the board slightly and redo my KiCad layouts to fit 5mm caps. Will the 47uF to 22uF increase in bypass capacitance REALLY make any difference? My power supplies are superbly well-filtered to begin with so I kinda doubt that it would, but I am wondering in case my design gets used in other equipment that has less robust power supplies. Opinions?

For or against establishing a sticky thread with a basic methodology, the necessary tools and the basic rules before any intervention, troubleshooting, upgrade, recapitulation, massacre, for noobs?

Like many here, I like to help with repairs but I'm more and more annoyed to see beautiful devices massacred or even destroyed following a "simple" recap.
We could first lay the foundations (for those who wish to participate), then gather the right information and then put them in their order of importance and create a sticky thread as a reference guide.
I'm very busy in "real life" but if we get together, we should be able to create this in a few weeks.
Tell me .

The CD player has always worked fine until recently. It has static noise in the left channel with both RCA and XLR output. There's still music playing in both channels (same volume). The CD player was fully recapped 2 years ago. Could a worn laser effect one channel?Any idea what might cause this?

Hi folks,

I have built SS guitar power amplifier based on Dr. Bora Jagodic amplifier Legend 100W.
I changed the circuit only by adding mixed-mode feedback to raise output impedance to about 24 ohms.
I have tested amplifier in rehearseal room and there is significant change in sound when amplifier is pluggen into 16 Ohms vs 4 Ohms.
Into 4 Ohms it sounds right, but into 16 Ohms there is too much bass and highs are rolled off too much.
What can be causing it? Oscillation?

Thanks for suggestions

Hello, I havent been active in a long time because life got in the way, was going to create a new account here then realized I already HAD one a long time ago when things were... better. 😛 (pre-corona world, more money available, etc.)

Anyway...

So i'm planning on building some PA speakers. There's no rush, because I wont have anywhere to store them for like a year, it's just what I like to call a "slow research" project. I might get busy with life for a month or two, remember I have the same problem needing solutions and come back, just so people know.

I'm a big fan of Bill Fitzmaurice's designs. Or at least i'm a big fan of his logic anyway, I mean it all makes sense to me. Short version I plan to finally order his all everything CD sometime this year and once I have the storage space start building things - even if i'm not sure what specific things.

What i'm wondering is what ELSE should I consider building, ordering plans for, or outright buying on the used market?


I should probably start over from zero so were all on the same page though. 🙂

I'm looking for advice for how far DIY PA speakers can take me. On one hand i'm between bands (for a long time now) but was wanting to get back into music, build some things up as a hobby, and eventually play smaller gigs. I've also been taking some sound production type classes going back to college after many years as well and slowly learning about everything up to power shaded inverted J-stacks - but i'm guessing for insurance reasons and other hassles flying speakers MAY be more than i'm looking to do. I would also like to have stuff to borrow to kids/nephews/friends if they want to go run a PA rig for a little side cash (not planning to really do this myself, too busy). If someone wants to rent it - fine with me long as it doesn't blow up - but it's not going to be big shows needing tech riders playing for 10,000 people.

Just because i'm learning more about HOW some things are done for bigger live sound I have no experience yet, so i'm totally open to well meaning advice steering me to consider other designs along with, or instead of, or just buying used gear.

I don't know how big of shows I will "need" to play, I don't know if the realistic upper limit for what i'm planning will be 500 people or 2000 people or what. Feel free to suggest though.

My most salient points and thinking process that steered me to Bill's stuff:

- #1 I want good sound. I've heard too many rigs even commercial rigs that suck. People should be saying "holy crap did that sound amazing".

- #2 all this including the woodworking itself to build, the gigs, and borrowing to others my PA gear is basically a hobby to start, until or unless it's not. I may build more equipment than is strictly needed for the smallest starting shows because i'm using speakers elsewhere when not at a gig or sending the nephew off with a PA setup while i'm playing somewhere else one weekend.

Strict analysis of cashflow isn't required at the outset for a hobby, things like the need to buy used name brand gear because you can sell it for what you got it for is not (at this point) my top priority. I'm also not trying to make pointless work for myself just to match what can easily be bought better I mean, like if building subs is smart but tops not worth the work, you can push me in that direction. Yet I expect to have two or even three complete sets of speakers to cover "small, medium, and 'large-relative' gigs" - I'd like to buybuild once and be set for the next two decades that I can say yes to any situation that wants to book the band that needs us to bring PA gear or has a questionable quality house PA. Ending up with 6 or 8 LABhorns, Tubas, or possibly 12pi's and the tops to match is not at all out of the question, but how big of a show will that play to blow peoples socks off? Much beyond that exceeds the hobby budget.

My assumption is even bigger gigs would HAVE a good PA to plug into, so i'm just looking for the system that will help "make a name" by saying Yes to any gig that calls and giving them amazing sound even if we have to haul it ourself to insure that sound.


- Now you might be already wanting to suggest speakers whose bass will make the gods weep but - we plan to self roadie things. After a night of playing hauling those cabs back out get heavier. I might be able to get another db or two from heavier wood but Bill's use of lighter wood and more bracing and smaller overall pack space makes sense to me. Also not having monster cabs with 2-8 drivers. Plus i'm less keen on stacking things three high for instance. Keep It Simple.

- Will need deep bass. I'm prone to things like Pendulum, but assuming a rig that will cover anything from rock thru drum'n'bass is a good plan, so his Tuba cabs over Titan cabs if I go Bill trading extension for outright efficiency matters. LABhorns? 12pi? I understand and accept that things like LABhorns are meant to run like at least 4 preferably 6-8, just tell me the space needed for monster bass. Yet systems that scale down for smaller gigs (or other speakers - I want to build some of his Tuba HT's for home theater too anyways, someone else used them for a PA in the corners and said they worked great) are also relevant.

- Pack space matters more for the small or/and medium rig because the large rig would have a dedicated trailer. If less than 4 LABhorns sound like crap we need a different speaker for those situations, also the idea of two speakers on more power with less pack space that might produce the same volume as four is nice on one hand, unless the cabs are painfully heavy or we dont have the plug power. I dont want to haul 8 LABhorns to every single situation, but i'm not against having different speakers for different gigs and loading the ones I need. If we have to go down stairs (and some places I expect to possibly play require that) those lighter Tubas start looking more desirable than a louder or more efficient 12pi, the latter may not even always fit either.

- Efficiency matters. I know Bill's designs push for efficiency, even if not absolute efficiency at all costs, but gigs with limited amplifier power are likely. But so is having more than one set of speakers if there's a big difference.



Lots of detail! Hopefully not too much. In my mind everything steers me to his designs - OR considering LABhorns - but i'm very curious what else is worth a consideration!

In looking for the next project I stumbled on to information about System Audio's design process of Pandion speakers. It seems that the designs were largely based on volunteer work and some or maybe all of the data was published on a blog.

I've seen that there were two versions: evolution and revolution. I understand that the evolution became Pandion 2 and revolution became Pandion 30. I don't know how close the final evolution/revolution information is to the Pandion 2/30.

I am having difficulty in finding the the designs of the final Q113 and/or Pandion.

Does anyone have diagrams/drawings/schematics/parts list for Q113?

Thanks!

SOLD

Asking $65 to include ground USA shipping. These are retailing now for $40 / each plus shipping from Antek.

For sale are a pair of Antek shielded AS-2218 200VA 18V transformers.

One is open package, I shortened the primary wires a half inch to twist them together for testing. Never used in an amp.

The other is still sealed in its box.

I still have my working original Hafler DH-200 and was thinking about doing a board upgrade. What are the latest options?

Hi there!
I am planning to build a couple of subwooferes for playing music aimed at the lowest notes, size limited to 200-220 litres.
And saw this driver by RCF, the LF18N408.
Xmax +/- 15mm. fs 30Hz
No comments on the web yet.
Has anyone used it?
I was planning to tune the box at 30hz.
Would it be recommended for this use?
What size to be used in a better way?
As well, seems to offer as well very good performance/price ratio both the Beyma 18PWB100 Fe and RCF LF18N405. Any opinions on those?
Thanks and regards from Spain.
Antonio

My friend went to Auckland, New Zealand to shoot a short film. Unfortunately, the sennheiser 8060 is working at all. So I came here to find the equipment hire. Can I get some help? Or if u guys knew some equipment hire shop in auckland, please tell me 🙁

Hi new member here.
Connected old Denon 8r integrated and 8 power amp which are biwired to replacement speakers without noticing they had jumper strips fitted. Blown internal fuse. Fitted the spare and that blew.

Any ideas on what I will have damaged and whether viable to repair?

Many thanks in advance
Mark

I removed the jumpers at the rear of the speakers before trying the spare fuse

The integrated amp blew . The power amp still powers up

Hi. Just finished the ACA mini build and biased it last night. Tested it with Schiit SYS and cd player and sounded good. Today, I moved some things around to make room for all the stuff, and one of the speaker wires came loose. Reconnected and now, when I fire the thing up, loud feedback/buzz/noise from one side (red). Any ideas what I should check appreciated.

I brought home a Yamaha YST-FSW150 powered sub from Goodwill for 20 bucks the other day. It runs well at low volume levels, but there's some very obvious distortion at normal listening levels and above, about 25% on the volume dial. With a sine generator, the resonant frequency is about 65Hz, and it tails off about 10Hz in either direction. The unit is from 2011—barely 10 years old. I'd like to get it working so I don't have to shell out for a new sub 😉

I don't hear anything rattling around inside when I carry it around, and sure enough, I found nothing loose inside the chassis when I took off the rear/bottom panels and driver. The distortion is the same in both the down- and side-firing orientations, or even if I lift the sub off the floor. The noise is definitely coming from inside the box, not from some piece of furniture. Pressing on different spots on the outside of the box (and down the inside of the port as far as I could reach), I couldn't find anything vibrating.

Taking any one panel off the box instantly fixes the buzzing, but also makes it not much of a subwoofer anymore. This means I can't just reach around inside and feel for the vibrating part, or even look inside while it's running. I think this at least rules out the electronics; it must be an acoustic/mechanical issue. However, all parts on the inside of the chassis feel 100% solid, so I have no clue what could be making this noise

The driver cone looks visually fine, and as mentioned, the buzzing completely stops if I break the resonant chamber by removing a panel, so I don't think it's blown out.

I've taken a few blind swings in the dark, to no avail:

• I ziptied some wires together to prevent them from touching the chassis walls
• The magnetic-shielding plate looked loose at the corners so I pried it off. (The glue was still completely fine in the middle, as I found out.)

What else could even be the source? I can only take the panels on and off so many times before the screw holes strip out, so any tips are appreciated.

Soul Note S3 Ver 2 SACD PLAYER
Soul Note Japan offeres me a unit of S-3 ver2. for demo
The shipping weight is 36Kgs..
https://www.kcsr.co.jp/detail_s3.html



[URL='https://flic.kr/p/2mU7Vf1']

Wondering about the sound system at Royal Albert Hall. Have a couple of recordings from there. One is a Blueray of David Gilmore and the other one is Joe Bonamassa. Have had the Gilmore recording for a few years. While the music was good the sound was not very good. Pretty much unlistenable distortion for me at mid and high frequencies. Always wondered if it had been recorded with one of the early digital snakes (a snake being the cable that carries mic signals from the stage to the mixing console out in the house).

Just got a copy today of a Joe Bonamassa CD set recorded at Royal Albert Hall. Reason for getting it was I heard music from it in a couple online listening session videos and thought the guitar sounded strangely metallic. Hearing the CD today reminds me of the David Gilmore recording. Don't think I will play the Bonamassa CD more than once. Would like to enjoy the music, but hard to put up with the ugly (to me) distortion.

Anyone else notice this? Is it a feature of Royal Albert Hall recordings over some time period? Just wondering.

Free, just pay shipping. I'm in UK but happy to post anywhere.

FS a pair of SB Acoustics 7.5" Satori TeXtreme 4 ohm

used very little

price 429 euro

Please PM

Looking to purchase two of these for a project.

I’ve read various blog entries about the LM3886 and the circuits people have made

Two suggestions I’ve seen that don’t always seem universal are the following, and I’m just curious how often they are implemented?

1) the data sheet sort of makes a passive mention about a 220pf capacitor between the inputs to help with oscillations, especially with those that come in via the input terminals. Is that pretty standard? I don’t see it in a lot of PCBs, so I’m guessing the ones who do it solder directly to the lm3866 pins?
2) I’ve also seen mention of putting a larger 100k resistor between the input and ground, but before the DC blocking capacitor. Apparently this helps prevent the capacitor from accumulating a charge when no input is connected. What’s the side effect of doing vs not doing this?

Thanks.

I recently managed to blow the left output channels on a pair of 3BST amplifiers (most likely due to inadvertently touching the ends of the speaker cable together while under power. Face, meet palm...). Both internal and external fuses blew on the left channels, along with a number of output transistors. After talking briefly with Bryston tech support, I consolidated the two working channel modules into one functional amp and set about repairing the others. I've managed to replace all the transistors on the bad channels, put the respective channel modules back in their proper amps, re-bias the transistors, and adjust the DC offset down to somewhere under <1mV. Amp #1 seems to be working fine and, if anything, sounds as good as, or better than it did before. Amp #2 appears to give correct bias and offset readings, powers on normally, and initially gave a rather feeble output signal on one channel and then quietly crackled into silence over the course of maybe 20-30 seconds, and now refuses to produce any output whatsoever. I put a cheap oscilloscope on the outputs and, as expected, it's a lifeless, flat line. It's rather odd that both outputs are non-functional, since one was working before when installed in the other amp. So perhaps something beyond the channel modules is bad.

At this point, I'm hitting the limits of my diagnostic skills, and am running out of ideas. Can anyone suggest what I might check next to get a better idea of what might be going on here? A month ago I barely knew which end of a multimeter to point at a circuit, and now I'm reading technical whitepapers on class AB amps. I'm not experienced, but I'm a quick study...

If anyone is interested in this instrument PM me and we can discuss price. It is undamaged and in working order.

Cheers,
ceulrich

I have a somewhat specific question.
it is said that the karlson cabinet makes the loudspeaker work so that the reproduction of the sound can take place with smaller cone excursions compared to loudspeakers placed in other types of cabinets.
I think that this effect is generated by the air pressure that is generated in the chamber of the cabinet.
I would like to know what the loudspeaker coil does, what it does and how it behaves in this case, ie when the loudspeaker coil moves less. Back EMF for example.
this type of loading has characteristic negative effects, two cancellation peaks typically located at 180Hz and 600Hz.
this question is asked because I would like to understand if an amplifier with motional feedback can remove the two cancellation peaks.

Hi guys!
After long research,discusion and space menangment,plan is finished!
I'm gona build a sealed subwoofer,in box of 120l. In that 120l is everything calculated,driver,bracing,damping.
Woofer is Eminence Kappa pro 18lf-8.
Yamaha P3200 in bridge mode will be power monobloc for woofer.
I'm also gona make linkwitz transform in try to get as flat as posible down to 20Hz.
Woofer is big,amp is big so i have place for at least 20dB gain if needed.
I will use woofer in home setup for music,maybe some time for movies,but music is first plan.
Woofer will play L i R chanel in mono mode,it have only 1 coil.
And that will be help to my Dallas II with Fostex FE206EN and Monacor super tweeter driven by KT88 SE amp.
They play almost flat from 55Hz to 15000Hz,+/-3dB.
I'm happy with that but i want low end.
For now i put woofer in H frame,and its driven with subwoofer modul 150W 8Ohm,with activ crossover. Its ok,but is not linear and i think that can be much cleaner without thos subwoofer module.
So,the only thing wich is left undefined is crossover,low pass filter.
What to use for that purpose,what will you use in this situation and why.
Passive or active? I know there are nice analog active crossover,but 3k€ is waaaay to much for me in this situation.
I will take signal from KT88 SE speaker out,paralel with Dallas.
So im not sure what to use. Some old speaker builder,from MIR AUDIO told me to use passive and nothing else,that everything else will color signal.
And if this is the best way to go,what to do with phase if in the end i need to switch it?

Hi friends
I have got myself a pair of speaker wires, a Mogami 2804...
That's a rather thin, stiff, expensive little diva of a beast. (I like it 😛 )
But I'm worried about it wearing out due to mechanical stress (plugging, weight, inadvertent pulls etc.), and am looking for tips about stress-relief techniques. As it's a coax with each "lead" (outer/inner ... core?) going into its own banana or spade connector, how can I mechanically improve these last few cm ?
Thank you

Hello,

I recently obtained a pioneer sx-110 (1965 manufacture date). It has 7868 finals. I’m studying the schematics before replacing all the original (bad) paper-oil caps, and they suggest a rather unusual operating point compared to all other 7868 receivers and amplifiers I’ve looked at. Unless I’m reading something wrong (or the schematic is wrong), it looks like it has a really high B+ for the tube, yet a low quiescent current.

I see 495v and 94mA going to all four plates; or 23.5 mA for each tube.

Usually, for other amplifiers using the 7868, I see B+ around 425-475ish and 35-40mA-ish going into each tube.

Other pioneer receivers or amplifiers from the same era with 7868 finals seem in line with just about every other I’ve seen:

SX-2000: 460v, 35.75 mA
SA-810: 425v, 36 mA

Whereas:
SX-110: 495v, 23.5 mA

Here is the relevant part of the schematic. Could I be reading a number wrong? Bad math? Could it be a misprint? If it’s correct, what do you think the designers were going for with high voltage but biasing the tubes rather cold?

Thanks for the help!

Hello guys, i want to change the internal wiring to improve the singlas quality ( rca->selector->potentiometer->premamp->ampl) . Do u have any suggested wires thay i can use ?

Hello all, new member to the forums.

I am currently building my firsts DIY subwoofer. Sub will be sealed in a small 1-1.5 ft3 enclosure. Sub will be passive, with external amplification. I will decide on final enclosure size when I am better familiar with WinISD. I have a mini DSP HD which will be performed EQ.

In addition to the build, this will be my first foray into woodworking. I tried mocking up a box with the skill saw, and all my pieces were cut poorly. I have amassed scrap wood to practice cuts. Given my poor skills, I bought a cheap driver to fool around with. Until I am confident, I can build something decently.

Driver: https://hertz-audio.com/product/car-audio-subwoofers-uno-s300s4/

So right off the bat, in WinIsd, I made three of the same units all with a 1.5 ft3 box. The first is the box with no eq or filters. The system input power is ~200W. The driver can handle 250W RMS, but cone excursion hits the limit in this box size.


In the second unit, I applied a Linkwitz Transform. I did some reading. This is optimal for sealed boxes. I want to learn more about the LW Transform and have had difficulty finding literature online pertaining to its application in WinISD. The stock box is shown with the lower transfer function magnitude. Speaking of which, what parameters do I change in the LW transform? Or is it best to leave stock? Which is what I believe I did.


In the Third box, I applied parametric EQ with a 6DB boost at 30Hz. It looks slightly better than the stock box, but all of them look horrible compared to the LW transform.



Now for the part im having difficulty with when looking at cone excursion. The stock box handles 200W with no issues.


LW transform is okay until you hit 20Hz. Anything below will blow the driver. Input power has to be turned down to an abysmal 5W.


Parametric EQ with 6Db boost. Wattage has to be lowered to 50W. I am guessing because this driver has only a tiny 250RMS handling and a small X-max of 9MM. Is there not much room for improvement?



I am completely lost on the SPL plot. I can see the boost at 30hz on the Parametric eq, and the LW transform plot is the flattest of the bunch. However, The stock box still has the loudest SPL at all frequencies above 20Hz. Looking back at the first chart (Transfer function magnitude). How do I go about interpreting The best DSP for my box? I have yet to fool around with high-pass filters. I would need some insight into best practices. Or where I can find resources.






I am new to audio.

Apologies in advance if this was posted in the wrong forum. I wasn't sure if this was more of a subwoofer post or a SOFTWARE post.

Hi,

Looking for a couple of 2SC1681's NOS anyone have any?

I am using audio interface to measure THD of the amplifier and I run ARTA on my PC.

When I connect amp out to the input of the audio interface I get a lot of interference.

Is there a proper way to do this?

Below is the schematics how I currently have it:



I am using Focusrite Scarlett 2i4 audio interface:

Dear all,
I would like to build this speaker here:
Faital-3WC
Since I am a Newbie, I have a few questions.

1. The wood used should be 20mm Baltic Birch Plywood. However, I checked many shops but this is basically not available here... only alternative is Beech Plywood 20mm. Do you think this can make a severe difference?

2. I would like to buy the crossovers from the page. However, I think the price differences between two similar sets are extreme. Please compare page 1 and 3 here.
http://www.jantzen-audio.com/wp-con...-Way-Classic-All-kit-versions-with-prices.pdf
What do you think, how relevant is this? I mean, about 700€ for a slightly different material? Will I hear this? Is it worth the money?😕

More questions will follow soon I guess... thanks a lot, any help is appreciated 😀

It pains me to admit I efffed up, but I want to spread the word to others here so they don't make the same mistake.

I added weight to my Emimence KL3012HOs to get the TSP specs and efficiency where I wanted them so I could cheap out and not order the C0RRECT drivers to begin with. The woofers were going to be used as the LF in a 2.5 way along with the KL3012CX coax drivers. Well, against my instincts I used Neoprene loaded adhesive (aka 3m weather strip adhesive) as it stays flexible and can be gradually added to obtain exact weight. YES, I SHOULD HAVE USED EPOXY, but only had the grey JB weld on hand, which shouldn't be used on the moving assembly of a speaker due to it containing iron particals as filler. Anyways, I embedded a coil of 12 awg copper wire (loop not closed to avoid a shorted turn) so the added weight came to 13 grams. Everything went well and I got the weight bang on. I've used this technique a few times before with success, but with liquid glue, not this thicker consistency stuff.

Well, now the part where I found out that I screwed up - I put the drivers on the sine wave gen and swept with 16V. The first one was perfecf, but low and behold I had a noticeable resonance spike on the other in the FR curve at 1 k. This turned out to be the copper loop buzzing on a spot where apparently the glue didn't get or stay in between the copper and cone. I tried injecting cyano glue and retesting, but the buzz was still there. I then tried cutting a slit into the glue and adding more cyano, but it was pointless. The other driver is perfect without any issues.

The moral of this story is ONLY USE EPOXY to glue anything on the moving assembly of a speaker (poly cones excluded). Otherwise it will end up buzzing or making other undesirable strange noises which could only be detected by THD measurements. Now I'm stuck with 2 paperweights to the tune of over $500. I feel like a complete idiot.

On the plus side (if there is one), I put the one driver on the sine gen and ran the driver at 40V free air around 100hz. Couldn't kill the thing running it there over 5 min which is a testament to Eminence durability. However, the suspension was so stressed at that point it was worn out and felt like a woofer that played for several years at full power in a dive bar. The KL3012HO is not a good dedicated LF driver, but rather a midbass. It should not be used over its small xmax limit.

Now I'm stuck ordering the correct drivers i should have to begin with (KL3012LFs). I may recone these others but Eminence doesn't usually sell recone kits for these outright. I may have to ship these to Eminence. Oh well...

Just another of those idle thoughts I get sometimes.
But if the floor space isn't available and the boxes are not too heavy would mounting HT subs up at the wall-ceiling boundary be any different?
Something to ponder perhaps if mounting in the roof cavity isn't an option and WAF was high

a friend has one or two of them or a mono version (- guy did not fully explain and I've seen the amp nor pictures other than someone else's blog for S120) - one channel (or amp?) needs repair and the company that built them does not supply schematics. They had a extra output terminal for use with a motional feedback subwoofer.

When the amp owner talked to a service person there was some mention of Sanken outputs which aren't made anymore but some output were made in California.

A sketch or service schematic would be greatly appreciated

sorry not to have better details.

Here's a blog on the amp

https://www-cfc1962-it.translate.go..._sl=it&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp

Hi
My Dynaudio D28/2 tweeters are over 20 years old, and I'd like to get them repaired or find
replacements; however, Dynaudio components are no longer being sold.
Anyone know where to get repair/replacement?

There have been sellers of "David Louis D28S" (and other models) tweeters on e8ay over the past several years. Most recently they claim iin their listings:

"The 28MM dome made from the same factory as Dynaudio...
Sound style: natural, detailed, and transparent.
sound very close to the Dynaudio style"

I am interested, but sceptical. When the D.L. tweeters cost <$30 I ignored them. Now its $75-$145 ea!! They must be better now(?)

The data in the listings appear to be generic, and I haven't located any reliable test/results.
Anyone here try these, have experience or know anything about them?
Thanks.

This may be an oddball question, but I'm asking it in earnest:

The horn on my EAW speakers is made from two pieces. Where they come together is very far from smooth. In fact, there is a very noticeable "gully" that runs the entire length of the horn, front to back, on both the top and bottom. (FWIW, this is on a BMS 4594 coaxial)

It seems to me that this should be smooth, and I'm wondering if this could be physically affecting the HF response / dispersion a little bit?

If so, would it theoretically be a good idea to try and fill these gullys in?
And if so, what might do a good, permanent job of it? (It's very slick plastic, of course.)

Neotech NEP 3003 power cable terminated with Furutech USA main plug FI28M(Gold plated) and USA C13 IEC plug FI28(Gold plated).

FI28 series connectors are most selling product of Furutech make a very positive connection with a tight fit.

Neotech NEP 3003 is made of 3 conductor(13 AWG each) Ultra pure Ohno Continuous Cast copper. This is very high quality shielded cable from Neotech.

It always sounds musical and engaging without any harshness or treble grain.
Excellent for preamplifiers, DAC and source components.

Cable length is 1 meter and professionally build.

Cable is fully Functional and cosmetically in good shape.

Neotech wire is light used and Furutech connectors are bit old(3.5 years).


Selling at very reasonable price of $130 including PayPal fee 5.5%.

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
AudioQuest Mistral power cable terminated with Furutech USA main plug FI-11M-N1(Gold plated) and USA C13 IEC plug FI28(Gold plated).

FI11 and FI28 series connectors are most selling product of Furutech make a very positive connection with a tight fit.

AudioQuest Mistral offers greater sustained current flow via its large 3.31mm2 conductors consisting of a combination of Perfect-Surface Copper+ and Long-Grain Copper. This combination increases the current of power entering into equipment (such as amplifiers, streamers, cd players etc.) and ultimately improving dynamics while reducing noise-floors within system.

Overall sound signature is greater clarity with a wider soundstage, breathtaking dynamic range and non-existent noise-floor.
Excellent for Power Amplifier, preamplifiers, DAC and source components.

Cable length is 1 meter and professionally build. Black color Techflex braid is kept on cable for nicer look.

Cable is fully Functional and cosmetically in excellent shape.

AudioQuest wire is light used (6 months) and Furutech connectors are bit old(2.5 years).

Selling at very reasonable price of $170 including PayPal fee 5.5%.

-----------------------------------------------------------------------------------------------------------------------
Shipping to Worldwide at buyer's risk, but it will packed carefully.
Please contact me for shipping charges to your location.

Thanks for looking.

FOR SALE one KEF T52 SP1049 Tweeter
I bought one NOS condition unit for spare in oprder to restore a pair of old Kef 105.1 And I realised that the problem was not the tweeter but the crossover. A dead cap.
So, I have KEF T52 SP1049 Tweeter for sale as long as I won't use it.
I'm asking 80€ plus shipping and Pp costs if they apply.
Although the seller at ebay said it was never used you can see it's been installen adn there are some marks in the dome, but I have tested it and it is in perfect working condition.

I have an audio, two channel, potentiometer that I removed from a tube amplifier kit I built a while ago. Adding it to the ACA Mini would there be a decrease in volume? Does adding this potentiometer introduce anything negative?

Hi,

I was given pair of Alesis point 7 monitors. They seem well built, but when mixing in reverb I noticed plenty of the higher frequencies, but a bit empty where the richness is. Is there a change of components in the crossover that I could do that could help? I wouldn't want to change values, but upgrade quality.

Could I ask for advice on which components, if any, could provide a more natural sound?

Thanks

Hello everyone,

Does anyone have the schematic for the SFL-2 preamp PSU? Or, the Service/Repair Manual?

Thanks in advance for your support.

Can someone put these to use? I've been converting my First Watt clone amps to the H9KPXG switch/soft start. These terminal strips with CL-60 are no longer needed. Yours for the cost of shipping.

This is my recently finished copy of the Aleph XOno. I finally had time to have a proper listening session earlier this week and get the cartridge loading and gain settings to where I was satisfied. The time and money spent was well worth it. I really can't see me needing to make any other phono amp! It is so, so good.

My next challenge is to bring the rest of the system up to same standard as it is streets ahead of my Naim set up.

The boards came from Willkommen auf meiner DIY Audio Homepage - RStAudio.de and are of excellent quality. His documentation and support is also excellent. You will notice that there are no 10uF capacitors at the bottom of the board. These have been replaced by DC servos with very good effect.

We had the best car racer: J.M. Fangio.
We have the best football player (Soccer): Lio Messi.
We had the best football player (Soccer): D. A Maradona.
We have a queen in Holland: Máxima.
now, we have an Argentine Pope.

Next steep: the forum, ja ja ja...

Congratulations and good luck Jorge Mario Bergoglio!, although I'm atheist.