Hi

Now i am on a project building a portable mini full range speaker based on TangBand W3-593 driver. Now i currently house it in a 2.5 L ported box tuned about 110Hz using a 2inch diameter port. I am going to include a mono class D TPA3116D2 amplifier and also along with bluetooth module to make it a handy unit

The TangBand felt a little natural and balanced sound which felt it was lacking on the Low Bass end .... it still produces fair amount of bass but not something up to my expectation. I retuned it lower to around 90hz by adding another 90 degree elbow to increase the port length and the difference was not much ...

Any other Alternative drivers which suites for this application? thanks ... those i found locally were just below par than the TangBand which end up sounding worse than the TangBand ... i am looking for something which can deliver more agressive bass at the lower end and drum bass ... treble if lacking i can just simply add a tweeter and perhaps relocate the port to the rear

hi I have 2 LM3886T chips around and have been reading in the forums that I need to isolate the chip when I connect it to a heat sink I just wanted to know what types of pads I should use in-between the heat sink and the chip and also what kind of thermal compound would you recommend (is normal cpu thermal compound good to use?)


Thanks

Built a quick and dirty TL sub with one inch foam core wrapped it in some particle board I had. It's tuned to 40 and kicks like a mule! I love it.

I have another GRS 10 inch pro driver on the way so I can make a fresh and hopefully improved, sonically and ashentically, stereo pair.

I would like to use 3/8 material for the wrap but I could use 1/2 material. It's nice to have it lite and mobile. So it's probably a choice between plywood and chip board. Which one performs better?

Any other recommendations to sonically get the most quality bass out of it?

HI Everybody
Did anybody tried or tested that powersupply ?

Class-A Netzteil in Akku-Qualität, mit elektronischem Shuntwiderstand, die audiophile Masterversion eines Netzteils - Klasse-A Netzteil

I am looking to buy the best power supply to build a preamp.
thanks for your help 😀😀😀
Phil

hi i recently found an old amp with 3 12ax7 and decided to build a guitar preamp, to operate with the 250v i am using a dc boost so i dont have a transformer that gives me that voltage along with the 6.3v ac for the filament, currently the filament is working on 12v dc, but the tube gets very hot and in some posts they say this shortens the life of the filament, my question is, would there be some problem if I control the intensity of the filament with PWM like they do to control the intensity of a led in other projects?

Having a problem with my Sony amp. I’m getting white noise/ cracke and pops from both channels. No preamp connected, just the amp plugged in with a test speaker hooked up. Occurs in stereo and bridged mode and it is effected by the attenuator on the front panel slightly. I also worked deoxit into all of the controls with no improvement. Any ideas?

Hi guys, I have the SMSL connected via bluetooth. Then into a topping TP60 Amp. Sounds great.

What do the following modes mean? Does the PCM filter 1-6 even apply when connected via Bluetooth?

PCM FL1-6
DSD Filter Narrow / Wide
Sound Color 1-3
HighSound Enable / Disable ( I belive this is a highpass filter? but no sub out on amp so not sure )

If anyone has a thread or chart to reference to this would be great. What do these modes mean?

Thanks for the help

PS Why do you have to press C on remote before even operating the SMSL device?! Took me like 30 mins and 2x battery changes on remote to find this out.
----------------------------
M300 MKⅡ
Bluetooth Audio DAC
New series ID design, with glass panel, stylish and long life.
AKM's flagship audio DAC AK4497, Ultra-high SNR, ultra-low distortion, support DSD.
The 2nd XMOS solution, PCM supports up to 32bit/768kHz, and DSD supports up to DSD512, custom driver for Native DSD .
Two ultra-low phase noise crystal for 44.1/48kHz multiple frequencies.
Built-in high-efficiency power module and lots of low-noise LDOs provide pure power for analog circuit .
Lots of audio grade components, include MELF resistors, NP0 capacitor, Gold-plated jacks.
Use a 1.54-inch high-resolution full-view color IPS display, and the user can choose the color of fonts.
True balanced output and high-quality XLR connector.
6 digital filters for different music listening.
Full aluminum CNC milling chassis.

Not sure how this works. Bought a used MiniDSP 2x4, supposedly with software. Turns out the software is from 2018 and hence does not run without Flash, and the owner does not have the MiniDSP account data.

Can I just register with MiniDSP and buy a plug-in for $10 even if I don't have the original paperwork that came with the box?

Dear forum members,
I wish you all and your families the best of health, happiness and fulfillment in the new year of 2022 !

I would like to share my plans with you and hear your views 😊

So the story is:
I am building a house and already thinking about the sound system in the living room.

As you can see in the attached pictures, the tv will hang on the wall and a cabinet will stand under it. All this next to the entrance to the living room.

The distances shown in the figure are in meters

Therefore, due to lack of space, I will not use tower speakers next to the said cabinet.






The sound system will be designed for both listening to music and watching movies.
I have two options I am considering:

Option 1:

System: PC (For music FLAC, For movies) --HDMI CABLE--> Marantz SR5015 ---->

• L;R speakers: ELAC DEBUT REFERENCE DBR62 (one of the choices)
• C speaker: ELAC DEBUT REFERENCE DCR52 (one of the choices)
• SW - Subwoofer: SVS SB-2000 (one of the choices)
• S: Speakers in the ceiling

Since the bookshelf and the central speakers placed on the cabinet would not look very nice.
I would make a cabinet so that the speakers would be placed inside it.
For example:




----------------------------------------------------------------------------------------

Option 2:
To make a Custom Sound Console - Speaker | Inside would be drivers for L, R, C and a subwoofer driver.

System: PC (For music FLAC, For movies) -- HDMI CABLE--> Marantz SR5015 ---->

• L;R speakers: Drivers inside Custom Sound Console (could be midrange + tweeter OR one full range driver; because subwoofer would be responsible for 30 - 180 Hz region for example )
• C speaker: Drivers inside Custom Sound Console (same as L;R)
• SW - Subwoofer: Driver inside Custom Sound Console + Crown amp (for example Crown xti 1002) (Drivers: 1x12 OR 2x12 OR 1x15 inch)
• S: Speakers in the ceiling

---------------------------------------------------------------------------------------------


Since the space in front of the TV is about 29 square meters, I think ELAC speakers may be too weak for such an area. So maybe it is possible to choose drivers that are more powerful and have better sound quality than mentioned ELAC speakers + SVS SW?

What do you think about Option 1 VS Option 2?

Hi, probably a bit basic for here but i'm after a schematic for a Majik DS (the early one) its a PCAS 754/L1R3. A friend has pulled a cap off the board and looking for a schematic to find a point to hard wire to. I've asked Linn and nothing as yet (lol).

There is a schematic on Elektrotanya but it's for a PCAS 175 and the circuit component idents don't match at all.

Any help is appreciated.

Hi I wanna mod my LD I+ with 3.5mm female socket for preamp use with toggle switch.

But im wondering if I need to change the Coupling Cap Value to get good enough bass when feeding it to my power amp?

Hi folks,

I'm stuck with an old DSP PreAmp (cannot afford a newer one...) which works well, but does D>A with AD1853 followed by OpAmp I>V conversion and OpAmp driven Cinch outputs.

I'd like to implement balanced outputs and noticed applications which "just" use a 1:1 (or 2:1) Transformer with the DAC Chip Out+ and Out- and connect the transformer secondary to the balanced Cables/XLR.

My question (for lack of DAC knowledge):

Could I just cut the existing I>V (i.e. just not use both the existing I>V and the buffers driving unneeded cinch outputs) and instead connect the AD1853 Out +/- pins (12/13 & 16/17) directly to e.g. Lundahl LL7401 or LL2811 transformers' primaries and have the respective secondaries drive the balanced cables to the (already) balanced PowerAmp inputs?
Which other things should I consider? (Note: Volume control ist done in the digital domain, the existing PGA2310 is disabled anyway).

Thanks for your suggestions!
Regards,
Winfried

What happens to WooferTester / Smith & Larson ?

The 11th of november 2014, I damaged my WooferTester unit by inadvertenly injecting a too high voltage in the low current port.

I immediately sent a mail to S&L's Brian Smith. He answered me to send the box to their workshop. So I did it, the postal services indicate that the parcel was delivered the 2nd of december;

Some weeks later, having no news, I sent a few mails.
I had a response only the 4th of february : the unit will be repaired "soon".

Some weeks later, same as above, having no news, I sent a few more mails.
Answer, 16th of april : "I should be able to ship a repaired unit to you next week. The cost will be $250.00 which will include shipping."

Again silence from S&L, despite more mails I sent.

Until the 4th of may, a request through Paypal to pay the above $250.
I made the full payment immediately.

And since then, nothing arrived. No answer to my emails (two this week) asking to confirm that the unit was repaired and shipped and my request for the advise tracking details. The S&L phone line is either busy or connected to an answering machine.

So that's it.
I have a lot of WOO files (files generated by the WooferTester program) which can't be opened if the unit is not connected to the PC and which I can't exploit.
And I can't measure drivers as easily as formerly with WooferTester

Many diyers in France are accustomed to US companies as being very reactive and giving satisfaction to their customers within a few days.
Here it is not the case. I am very disappointed.

EDIT, 4th of june :
I received an email from Brian Smith this morning (4th of june), saying the unit still failed a test. I would have liked to be informed sooner, I paid for the repair a month ago.

EDIT, 13rd of july :
Despite having sent an email to S&L the 24th of june, I have been left in a dark silent for a week.
So trust had definitely gone and I gave up. I asked Paypal to have my money back.
Paypal informed me that the transaction for the money back was done the 3rd of july.

Hi All,

After serveral years I finally cleared out some DIYaudio stuff that I had laying around for a longggg time. These items can be picked up in Leiden, The Netherlands for small fee, say 100 euro?, that does not have to be anywhere near the price I paid for them. Most importantly I would be nice knowing some parts will get used by someone...


-2x Aleph-X PCBs
-2x PowerClone PCBs, including 6x LM3875TF
-2x IC Poweramp PCBs incl 2x LM4780TA and rectifiers
-2x IC Poweramp PCBs, without any parts
-2x GainClone PCBs incl 2xLM3875TF
-4x Aleph X PCBs + 8x Aleph CCS PCBs, no parts
- some unknow PCB's which look like a MC- pre -pre headamp, " phase optimized", and " ERNShow.com"
-4x Aleph 30 PCBs
- DAC PCB for 4x-PCM663PPK, CS8412/8414, SM5842 , dac-IC's
-JFET-BOZ PCB, most parts allready soldered, incl 2SK170 and 10uF AEON 10uF Truecap
-4x LM3886 gainclone PCB incl 4x LM3886T
-4x power regulator PCB.s incl 4x 63V, 10 000uF caps Rubycon
-2x gainclone PCb incl 2x LM3875TF
-some unknow PCB, which I believe is a Psslab DIY project for a Power JFET amplifier, including 2 power JFETS
- 2x power suply PCB, inlcu 16x ast rectifiers and 12x 1000uF caps
-Pass B1 BUF inlcuding power caps and 2Sk170's
-Gilmore LITE headphone amp PCB
-Power Supply PCB , I think for a Pass BOZ, incl 200V, 1200uF caps
-IRFP240 power MOSFETS, I count 56x
-power rectifiers, "CQ549, U860", I count 29x
-4x TDA7266 power amp IC's
-2x LM3875 PCB's incl LM3875TF
-4x Chipamp.com gainclone PCB's incl 4x LM1875 and 2x poewr supply PCB
-3x stereo headphone/preamp PCB for opamps, I believe these are from headfi.org, and are a pocket headphone amp prject PCB for 9V supply

• 2x Pass-Aleph3 PCBs
• 2x original Nelson Pass A40 project PCB's from a old article in an old magazine

-35x 2N5877 power BJT, maybe for the Nelson Pass A40?
-Pass SOBOZ preamp PCB, all parts solered, incl toroid transformers and power supply PCB.
-inverse RIAA filter, 12 Ohm output

• 2x Alesis Bi-amping poweramp (2x LM3886 + 2x LM2386 (?) )
• Pass BOZ, all parts soldered incl toroid transformer
• 230V to 2x 15V, 1A toroid transformer
• 230V to 2x 12V, 5A toroid transformer, two of them
• 230V to 15,17,19,21V , 15VA toroid potted transformer
• 220V to 2x 30V toroid transformer

in total
7 toroid transformers
20 gainclone PCB's incl power IC chips
56 power MOSFETS
18 PASS project PCBs
etc....

all in one box to go.

What do you think, is it worth 100 euro?

I am doing the router work now but hasnt received the drivers yet.

Does anyone know the coutout and rebate of the 22 cm Audio Note chassis?

Is it standard Seas 8 inch driver?

Ø 220,6 mm
Cutout ø >186,4 = reccomended ø 190
Rebate 5,5 mm

Hello,

I just bought used OB speakers. I dont have much listening space. Woofer is 15 inch, box in which it is fastened is 58 cm long (both sides open naturally). Is it possible to shorten it on both sides? Is there a formula to calculate minimal length?
Woofer sits in the middle.

Thanks, Gorazd

Looking for a pair of AER fullrange drivers. Let me know what you got.

Hello, I note that many of Toshiba's low noise transistor pairs have their emitters joined together in the package. This seems to rule out the possibility of linearisation using emitter degeneration resistors. Does anybody know of any alternative linearisation techniques that could be used? Or alternatively, does anybody have some design tips in using these transistor pairs on input stages to reduce distortion levels?

I have for sale 2 units AURA NSW2-326-8A.
It is a 2'' extended range loudspeaker.

Both units are in excellent condition.

Price is 25 Euros for both, plus shipping.

Hi, I'd like some help please , What is this Vr1 adjusting? , its on page 4 of the schematic, marked with red arrow.

Hoping that someone can steer me in the correct direction. I have a Brazilian style amp that arrived with just about every semiconductor bad. They all fell off the PCB, when removing the PCB.

A few of the semiconductors are defective, the. Dual diodes have failed, marked u1640s1 and u1640s2 . Based on measuring the good ones, there are common anode and common cathode. I found a U1660 aka (common cathode) but no luck finding the common Anode.

The u1640 appears to be a 400volt device, and I have installed the 1620 (200 volt) as a test . All is functional with the 200 volt installed.

Any suggestions? Keeping the TO220 case?

Hello !

I received a BOSE Sound Amplifier Basic Audi AS4 amplifier module, I want to use it as a separate amplifier, without optical connections,

I'm interested in whether the TDA 7566 works without I2Cbus - maybe someone has worked with it before without a controller.

Currently, if the module is powered, you can hear the protection relay switching on and then switching off after a few seconds.

Coupling again if pin 27 - Ring-break diagnostic wire is touched.

With audio signal on inputs I have no signal on output regardless of the relay.

I haven't unpacked it yet to take measurements on the IC board.

If I receive an answer from you that the TDA 7566 does not work without I2Cbus, the approach does not make sense anymore.

I don't even know pin 27 - Ring-break diagnostic wire if it's port in or out. It seems to be in.

Also I can not find any wiring for secondary connection (below Audi DSP T32h connector) - except one optical port.

Thanks

(For 2022, I have decided to downsize my system and am selling off most of my finished projects and those still in the queue)

Tubelab SPP with Hashimoto PT and 25W OPT.
Hammond 193 series 5H choke.
2nd filter cap a Mundorf 100uF polypropylene.
Solen Film & Foil coupling caps.
4 and 8 ohm output taps.
Flat frequency response is within -0.3dB +0.2dB from 20Hz to 20kHz at max output power.

Very clean build, sounds great and no issues.

Build cost approx $1500, I am asking $1400 + shipping.

Tubes not included but I have new matched quads of JJ and Sovtek EL84M, as well as many NOS pairs of 12AT7's.
If interested we can work something out.

I've got 28 of these new, unused, original boxes. I'd rather not part them out into quads...$100 takes the lot.

I have a Kenwood Basic C1 and one channel just quit on all inputs. I haven't opened it yet, but anyone know if this is a common problem and if there is something I should check first? I don't mind troubleshooting it, but if this is a common problem with a known fix, I'm all ears.
Thanks,
Mike

Need advice on resistor values for a stereo line level to mono instrument level attenuator.

The stereo line level will come from the tape output RCA connectors of an Onkyo receiver. The mono level will go into a guitar recorder device.

Here's the circuit that I'm thinking about:



Would R1 and R2 = 5.6k, R3=1k be good values? Better resistor values?

Quick run down:
Batt died because vehicle sat awhile
Attempted to jumo it with a schumacher battery starter, batt was too low so I just attached it to batt and used the charge feature.
Maybe coincidence but after car was recharged radio was dead, nothing happens when pressing ON button.
-Checked fuses, all good.
-Removed HU to probe connector, pins 1 and 11 supplied +12v constant and 12V when key turned to ACC ON, continuity between GND and body, good.
-Probed amp coNnector, 12v constant + 12v acc on is good. Continuity between GND pin and car body, good.
-Took HU to the bench, supplied pins 1 and 11 with +12VDC, try to turn on radio and nothing
-disassemble HU, remove CD Player/Changer + Tape deck to inspect main board.
-Notice slight heat discoloration near power transistor area, focused on two TO-252 (DPAK) 7256's
-Probe for V on Dpak, 12V on one (not sure what part of dpak is called but its the middle/main tab), ~3V on the other
-Probe face plate, confirm volume/on pot has continuity when button is depressed. Then verified it has voltage.
-probed various other areas and noted it in pictures attached.

Any clue what couldve caused this issue?
Worried if I replace the HU with another one it may cause damage again to HU.
I assume fixing this without schematic/parts list may be a foolish task?

p.s. I have higher resolution versions of my images if itd be helpful, just let me know

Thanks for your time gentlemen.
Will update if I figure out more

This is my first foray into class D amplifier repair, and so far I am stumped.

I purchased this amp on ebay for a very good price, but unfortunately it arrived damaged. Instead of sending it back, the seller just issued a full refund and told me to keep it. I was told that the amplifier worked, but it was pulled from an install, so who knows.

This is a 4 channel (4 in/4 out) amp that will not turn on.. or off. (Power LED is lit and the switching power xfmer hums away regardless of position) The power switch is not inline with the 120v line voltage entering the unit, and is instead controlled (presumably) by a combination of relays and IC's or some discreet array. Schematics are not available for this amp, so it's really hard (for me) to know.

The mosfets and voltage regulators test good. Fuses are fine. The relays also test good, however, one of the relays that is responsible for supplying 120v line voltage to the amplifier PCBs is not receiving the 24VDC at the coil necessary to engage the line voltage. This is only a symptom, though, and not the cause. I tried supplying 120v directly to the amp boards and no luck.

Unfortunately, there isn't a single component on any of the PCBs that appear to be "fried". Everything looks fine. I'm attaching a couple of photos of the board. Sorry for the atrocious quality; my camera is also dying! My hope is that someone can identify the topology and offer a jumping-off point.

Here goes my first attempt at a passive speaker 🙂

I've aimed for drivers with smooth rolloffs and/or allowing for a simple/minimal crossover. Other goals was decent sensitivity and power response.

So I've settled on 3 alternatives:

Seas W22NY001 + Wavecor TW030WA12
Seas W22NY001 + Morel CAT378
Seas A26RE4 + Morel CAT378

I've attached simulations and relevant files for the first two.
The latter combo has numerous battle tested crossovers out there.
Note the listening height in the simulations (phase only matches up at that height)

I really like waveguide tweeters that can be flattened out with a simple cap like the CAT378. And since Seas does their measurements on typical baffle sizes for each respective woofer size, their measurements include baffle step. Which makes things a lot easier to simulate. And their measurements are proven to be trusted.

Any input?

It is a multi-way loudspeaker with two 12-inch woofers. How I calculate that?

I have no sound coming out of an Elekit Tube Amplifier and have pulled out some diodes and resistors that returned wrong values from an initial run over with a multimeter. When I test with the component tester they fail but when I use the multimeter they appear ok. How can this be?

Happy soon-to-be New Year. My wife and I are building a new house and I will have a 50ft by 26ft rectangle basement that is all mine! I will be finishing it myself and will also share a wall with a separate 25ft by 25ft side room. Floors will remain concrete (covered in epoxy). 8 ft ceilings. Completely underground with only one egress window. I am doing my best to plan out my entertainment setup. I will be using an 86” QLED screen mounted on one of the 50 ft walls so viewing will be across the 26 ft not the full 50 ft length, tower fronts, ceiling surrounds and rears with a 7.2 receiver (Maybe a 9.1). My question is: would four separate sealed 12” subs placed in the corners running off a NV3000 give better low end than a F-20 with a Dayton ref 15 running off 500watt Bash amp? Math says the four 12s with more watts would be louder but I am a total rookie when it comes to horns. From what I have read they are super efficient. Not looking for huge SPL, want to dig deep and have some volume when needed. I will also be using a minidsp to help tame the concrete floor. 50% TV, 25% movies, 25% music. Like to stay under a $1k for just the sub/amp choice.

I've never been one to pay a lot of money for "kit" for quite a few decades, (unless you can count a Yamaha Tyros 5 leccy piano and a YTS62 tenor sax).

I've a 1970s Leak 2000 tuner/amp. I paid about sixty quid for it on eBay about fifteen years ago, it replaced a Philips 790 that I bought new in 1972. The "deal breaker" was a replacement had to have din sockets like the Philips, I couldn't be assed about having to change the leads. An advantage was that it had sockets for disc, tape, cassette, aux. I use them all except "tape."

I use it mostly for this.

Login to view embedded media
The Rock-Ola wallboxes cost around sixty quid each more than fifteen years ago, before people other than we vinyl jukebox owners knew you could use them for something other than a telephone directory. Try getting a good one with un-pitted chrome and working, at any price now. The second-hand 3rd gen iPods I use were less than a tenner each. The batteries don't need to hold a charge.

But a month ago the Leak started "motorboating." "So I sent it to the menders."
In the meantime I spotted one on eBay, which I was assured worked fine, but had a scruffy cabinet, lots of scratches..
They can go for well over £150, but I got it for £56.

I was aware that the "cabinet" is actually three bits of real veneer on... whatever, attached by a total of four screws to a metal frame. Some amplifiers cabinets of a similar era have a "faux" wood vinyl skin.



One side was worse than the other, it had probably been stored for years end-on. So I just sanded them down and polished them.



The top came up well I just needed to add a bit of wood dye to the polish after this.




Job done!
It's in perfect working order, right down to the AFC mute controls.
The original came back, checked over, but wouldn't "motorboat," I guess a capacitor might have been picking up something from some of my other gear.
I've now got it in my "office" (our box bedroom), it replaced a vintage Rotel tuner/amp,

Good evening, please bare with me on this as I’m a bit wet behind the ears when it comes to Amplifiers,

This eve I changed the bulbs in the VU meters to LED’s as the old ones had blown. My problem is when I turned it back on to test it there was a little pop sound and the magic smoke was released from the left channel amp board!

I took out the power amp board and I think I found the culprit, a fried resistor. But when I went to check the service manual to find the value it isn’t on the schematic so I removed the other channel to visually check and this resistor is not even present?

upon further inspection the transistors on the affected channel have been changed to 2SD555 and 2SB600 before I owned the amp as opposed to the original ones 2SD665 and 2SB645.

I downloaded the service manual for the 170DC and the resistor R731 is on the schematic as shown. What part does this resistor play? Did the tech make a mistake by putting it in or is it there to adjust for the different transistors??

Any help would be greatly appreciated

thanks

Matt

I've decided to sell my JLE 3255 amplifier....I upgraded to the Sylph-D200.

Some of the mods that Lester recommended are done. Includes the new addition dual supply input board with the OP1656. I never actually tried it with this but I removed the input caps in readiness.

Lester really knows how to make these sing nicely. Been sat in a box since getting the newer version and so I thought I'd let someone else enjoy it.

£80 plus postage

Hi, can anyone share files for the U22REX or point me to a website that may have them. Much appreciated.

I have a like new Bluesound Node for sale. It comes with the original box etc. and now offers the USB-audio output as promised by Bluesound with its Dec 2021 update.

$530 shipped CONUS

Short version: Is it worth upgrading from a srm-313 amplifier?

So basically I am wondering how much difference will the choice of amplifier have on the audio quality of the 007mk stax headphones?

The online consensus seems to be that anything made by stax is inadequate and using very expensive custom amps will transform the sound (often with emphasis on bass ive noticed).

Personally I drive mine using a srm-313 unit (normal+pro version) and I've never felt thay I need more power.

Good evening, I just received a nice Marantz CD-273 which is supposed to go to my daughter who just discovered how good CDs are. The seller put it into the box upside down (argh) directly on the floor (noooo) with all packing material on its belly. When it came, the transport was unstuck (see photo). I realised this only when it would not open.

I adjusted the mechanism and it opens and closes again. But the player still does not play. First oddity: as long as the tray is open the tray motor spins. Main problem: the player does not play CDs. When I insert one and press "close" the tray goes in, the laser does it focus work, but then stops and the display shows all zeros. and this is it. most keys, if touched, give an "error" message. to me, this seems like an electrical, rather mechanical problem. but maybe something got unstuck and I did not see it? the laser unit turns freely on its swing-arm, however.

It's entirely possible that the unit was already defective when the seller sent it. I have some experience with philips-based systems which need to have the griplets reflowed and caps in the servo circuits changed, but before getting all over the player in shotgun-fashion some of you might know the symptoms and can direct me towards a specific solution.



state upon arrival... now mechanically fixed, but player still defective.

Looking for at least 2 Maxim MAX420CPA opamps. Email me at bigskyaudiollp <at> gmail dot com

Hi,

I'm selling the following :

2x Mirand Audio A1 v1.2 amplifier modules (they have speaker protection built-in)
2x Mirand XLR balanced input module for the A1
2x Cresnet SMPS630G modules. I also have 2x unpopulated capacitor bank PCB to add to the SMPS

Everything is like new

How about SOLD$USD + shipping? (Not responsible for any taxes, customs, duties or any other fees)

Thanks
Do

Hello from the Netherlands!

I've been snooping around for a long time here and decided to make an account, so I can pitch in / ask dumb questions as well 😉

I'm putting together a bedroom system. I've got an amp I'd like to use, but it's a very low power tube amp (about 2.5 watts). I need to build a pair of speakers that will function adequately with that little power. The catch is, they must also be quite small. No more than 10 inches tall, and no more than 7 inches deep. I realize that Hoffman's Iron Law dictates that these speakers will not have great bass response, but that's OK for this particular system.

This Kanspea speaker kit from Fostex is all I have found so far that might fit the bill. It is a complete kit including the cabinets. I have access to a woodshop, a laser cutter, and other tools, so if I had plans, I could make the cabinets myself.

Any suggestions are welcome! Thanks all.

Hi all. I sell my lovely AERs. They had few use and always with low power SE amps (never more of few watts). I buyed from AER by Bert Doppenberg and were sold as Signature model (were selected by hand by AER and there are only a pencil mark on boxes).
I have one more AER MK1. I give it free with the pair.
Sound is something amazing, specially voices.
Price: 1600 eur + shipping + Paypal fees.

I finally have time on my hands to dig into some projects.
Small tube amps and full range speakers are my current obsession.

Current system involves my rebuilt Acoustat 1+1’s, driven by a Threshold T-100 (60W/ch Class A)
in a 17’x12’ acoustically treated room, still in progress…
Various sources embraced: CD, Tidal and the traditional 12” polycarbonate disc.

Thanks for this amazing resource!

SOLD

I purchased these back in April from Wantanabe. (see purchase receipt). I'm cleaning some things out and I will never get to building an amp with these. Same old story, too many project, too little time, etc. etc. There are exactly the way I received them from Wantanabe, zip tied together and wrapped in foil. I'm asking $175 for the pair shipped 1st Class in the CONUS. PM me if interested.

*Sold *

Over $1200 invested. Asking $550 + shipping.

Beautiful sounding unit designed by Nelson Pass for anyone wishing to go the analog route with their LXmini system. This unit is objectively much quieter (less hiss) than the miniDSP 4x10, and to my ears sounds much better.

Purchased new as an assembled unit from Frank at Linkwitz.store earlier this year, so it was professionally assembled/tested. It is currently set up with balanced XLR connections on both the inputs and the outputs. Internal wiring (XLR to PCB) was upgraded to Duelund 20ga copper wire. RCA jacks are included so if your rig uses single ended rather than balanced you can switch it over. This unit can run the LXmini by themselves, or a +2 configuration or the LXStudio configuration.

Includes power supply and previously mentioned RCA jacks as well as email documentation that was sent to me by Frank with the purchase.

I have these tubes I have no use for. Seem to all be NOS. Just pay the shipping and they're yours. PM me if interested.

RCA - 22BHN3A
ITT - &AG7
RCA - 6GW6
Sylvania - 18AJ10
Tung Sol - 6AH6
Sylvania - 6DG6GT
Sylvania - 12HG7
GE - 6MK8
RCA - 6KL8

Jim

GONE

I hope I'm not stepping on any toes here and not violating some kind of copywrite law.......A friend of mine received a Cricket Label Cutting machine for Christmas...I asked her if she could make me a logo for the front of my F5....We found that Microsoft Word Font "MISTRAL" is a perfect copy of the font that Nelson (or whomever) used....Here is the result. Easy to apply and looks great. If anyone wants one, send me an email and we'll work it out. rvb100 at comcast dot net

If this is in violation of a forum rule or some other breech, let me know and I'll remove it

Maybe it’s just bad luck, but after a little more than a year my sublime sounding Elrog 300B tubes died inside my TU8600. I confirmed this with the guidance and support of Victor. Through calls and emails and a pro bono shipment of 300B tubes for testing we concluded that the Elrog tubes had failed. I can’t afford nice new tubes right now, but when I can, you can be sure they won’t be Elrog and they will be from Victor.

Mary, an assembly worker at the Atwater Kent Radio factory in Philadelphia, was nineteen at the time this photo was taken.






You might be surprised to learn the photo was taken in 1925, using a glass plate negative.
It would appear that she could afford to own a watch and seems to have been engaged.
The photo was posted on a message board devoted to the restoration of vintage radio equipment. Someone found it on a website called "Shorpy" that hosts old photographs of life in the USA during the last 100 years and more.


More photos of the staff at the Atwater Kent factory in 1925.


http://historyinphotos.blogspot.com/2013/05/atwater-kent-radio-factory.html

I thought a couple years ago after TI purchased National Semi, they discontinued the much loved LM4562. The SOP8 package disappeared very quickly while the DIP8 was still available for a little while.

However I just now realised it is back in active production. When did this happen? Am I the only one who didn't know?!

LM4562 data sheet, product information and support | TI.com

I kind of assumed it had become the OPA1662 given very similar specs.

Hi guys, I'm looking for some compactron tubes with unusual heater voltages:

27LF6;
26LX6;
23SJ6(C);
23MB6;
12SJ6(C);
8950;
M2057;
24LQ6;
24JE6(C).

Looking for a dozen or so, preferably new, unused.
You got any you don't need anymore, or know of a possible source?

Jan

Good morning and happy new year!
I‘m a bit stuck with a restauration project I want to start this year: got a pair of thorens td 125 (mk ii as far as I can see), one of them is having electronic issues (strobe light goes on, motor does not spin), the second has a more mechanic problem: it spins, but off axis…

so I am still in the contemplating/info-gathering phase and haven‘t gotten into it really, so:

is there a known, obtainable replacement for the td125‘s motor? I haven’t found anything in this direction, and also don’t know yet what the type of motor this should/could be…

I would prefer a replacement that would allow me to keep the electronics (well, everything in fact) as authentic as possible…

thank you for insights!
Best of all
David

Hi Guys,

I'm got a gainclone pending final assembly when I'm done with the chassis work.

I'm thinking of tropicalising the PCBs.

Are there any disadvantages to or reasons not to apply a conformal coating to my pcbs?

Hi Guys,

A question regarding protecting the chassis earth point from corrosion.

A class I electronic device in a steel chassis (in this case an amplifier) must have the steel chassis connected to the centre earth pin in an IEC socket.

This also requires the chassis earth point to be bare metal with star washers etc.

Given that this point requires a bare steel connection is it plausible to protect this point from corrosion?

Is this even worth worrying about?

Could one perhaps spray a clear coat over the top of the earth connection once firmly in place?

Unused DIYA T-reg with BOM.
Asking $65 shipped, so you basically get the BOM for free.

I had one channel fail while doing LFE duty. The strange thing is, all of the .33R/5 watt output transistor emitter resistors failed on the PNP side with only 1 transistor failure out of 5. The driver on that side also failed as did its 2.7R/2watt resistor.
On the NPN side, 2 output transistors failed as did their corresponding emitter resistors.
Refer to the photo where failed transistors are facing up.

The other strange thing, R51 (which roasted) on the NPN side is listed as a 1K8R half watt as is its complimentary R52 (good) on the PNP. What is installed in those two positions are 180R / half watts.

R51 and R52 on the good amp module both have 180R as well however, every picture that I come across clearly has 1K8 installed. I`m thinking the amp must have left the factory that way as I can confirm that the amp was never opened by anyone witnessed by the tamper proof seal that was still intact on the heat sink modules.

Would that type of subsitution be responsible for that kind of failure? It`s worth noting the emitter resistors on the bad module were manufactured by SRECO and the good module has COLBER`s.
I do believe that BGW had issues with emitter resistors at some point but I dont recall the particulars.
Your thoughts would be appreciated.

To isolate the PC and DAC , it can support up to full usb2.0 highspeed mode , without GND connect from PC and DAC .

Hello,
in the last post I 've added some digital stuff with pictures
Ciao
Guglielmo


The title is strong but I'm only selling some audio parts(tubes, speakers, scope, osc, JVC,...) because I need some money for my new audio experiments.
If you are interested I can send you the list.
I can send everywhere. I'll quote the shipping.
Ciao
Guglielmo

I've been a faithful customer of USPS my entire life. Always thought it was good to support them, they seem like an underdog to me.

No more.

I ordered two tweeters from Madisound on DECEMBER FIRST and they're still in Wisconsin, over two weeks later.

My package has average 0.27 miles per hour over the last 15 days.

Tubes for sale

Selling NOS NIB tubes .
We will be selling tubes in bulk. Boxes of 200 minimum. Old stock New in box (usa brands only)
Pentodes / triodes and other.Some We have 20,000 to 100,000 of the same type all factory matched.
Looking for tube amplifier builders to contact me. Design your amplifier around high grade usa tubes. No used tubes for sale. Below wholesale prices. Let me know what types you need.
Thank you
Andy

I was at Antek ordering a torroid transformer. And at check out time they popped up a new product line. Apparently they are making torroid DC chokes now as well as their power units. (yeah). The last time I was at Antek early this year I didnt see anything in chokes.

Now I thought torroids and DC didnt get along? Is there a secret sauce to winding a torroid for DC choke use? These are priced pretty competitively.

Do you think one of these would work as a choke input configuration as well? Or is that just pushing it too far?

Tube Amp Parts - Filter Chokes - AnTek Products Corp

Now if they would start making OPT's! Plitron doesn't seem to cater to DIY the way they used to nor sell torroid OPT's. There is Torroidy in Poland and another company in Holland I think that make torroid OPT's. So a company in the USA making torroid OPTs would be cool considering they are heavy to ship.

When using XSim to model, should I be "tuning" the driver for baffle step loss below the baffle step frequency? For example I am doing a 2 1/2 way and my BSF is 350 hz. Should I tune the half woofer down 3 db for loss? Right now the sim shows the system Fr bumped up when in reality it should be flatter. Cant really fool the Mid woof.

Another related question: In a 2,5 way do the 2 woofers have to have independent boxes? I have the 2 sharing one box.

Thanks

Well, it's been a few years. My 1700B has decided to cease operation, so it really is time for a repair and full rebuild. Here's what I am planning:

• Replace all electrolytic caps in the unit. One of the main filter caps is dead, so it's time to do the lot.
• Replace all the carbon composition resistors. A quick check on half a dozen has shown a 15 ~ 25% upward drift. Why did ST use CC resistors? I've been using cracked carbon since the 1960s.
• I was going to replace the OP amps with LME49710 OP amps, but, well, you know. NLA. AD797s look like the best, available option. Any other suggestions?
• Replace all the opto couplers.

Any suggestions will be most welcome.

Reported so far:

* Underline

Hi Guys,
We would just like to get a indication from the DIY Members as to what color PCB's you would like for the wolverine project.
We are looking into what color/s we will choose for the EF3 and Wolverine IPS boards.

Please select:
One color from the EF3 options.
and
One color from the IPS options.

Is it possible to make a fairly hi efficient speaker (say 94 db) that approaches hi end audiophile quality sound? I see brands such as eminence, Faital etc but I dont know who makes the best sounding stuff. I am thinking 10 inch three way.

Hi everyone

I am about to build a set of BIB enclosures but I am torn on driver choice.

I have narrowed my choice down to either Markaudio Alpair 10.3 (new) and Jordan JX92s (used).

Which of these would you think makes a better speaker? I am personally erring towards Jordan's.

Also, I missing other options? I've looked as Fostex but they have a really wide product range it's kind of hard to see where to start - and the ones I have looked at it seems to be the case that once you start to increase the driver size you start losing top end frequencies and as you decrease it's size you start losing the bottom end - whereas the JX92s seem to have a good response across the board.

I also looked at Lowthers, but it seems as though they're a bit of an acquired taste don't suit all styles of music (and I listen to all sorts from classical to Jazz, to Rock to Electronic).

Happy to be correct on any of my base assumptions!
Thanks for any input!

Hi,

I'm trying to do the idling current adjustment on a Denon PMA-560 (steps in attachment).

In one step it needs a 1 kHz, 10 mV RMS signal to be applied. Would it be ok to use an iPhone app for this
("audio signal generator"), or am I better off buying a dedicated signal generator?

Also attached a screenshot of the audio signal generator app, and the output of an old scope on that signal
(voltage divider set to 10 mV).

thanks 🙂
happy 2022 🙂

I just got a Fisher BA-6000 amp, nice condition, working fine, but I want to change all the cap and improve the sound, power is enough for me.
Any idea how ?

https://www.hifiengine.com/manual_library/fisher/ba-6000.shtml

Been looking for a good copy of the service manual for this, the ones on the web loose all the detail when I try to enlarge them. I need the power supply section with good parts and voltage readings. Picked this thing up for cheap in a lot of equipment, so more of just a learning curve type thing as I have never worked on one of these before. So if anyone knows where I can get a service manual for this thing for free or a reasonable price I would be grateful.

I just saw a very interesting BLH design from Sonido of Hungary. Looks like for those with DIY skills it would be a fairly easy horn to build. I've attached a photo for you all to see.

Thetubeguy1954