Another look at how to measure the Baby Huey circuit
- By jhstewart9
- Tubes / Valves
- 3 Replies
Attachments
Switch-able Sound-base / Centre / Satellite Speaker
I changed my desktop speakers recently and was inspired when I lay them on their sides. I'm on a hybrid kick at the moment. I need a good quality sound when watching TV. I need extra oomph when enjoying music. I need serious warp power for watching movies.
Can this be wired?
Laying the Sony SS-Fe9s on their sides inspired me. Can I make a switch?
Pos 1: 4 x 3.5" woofers in a single cabinet would make an excellent sound-base for the TV (full-range, stereo),
Pos 2: (3.1) Centre woofers = centre channel. Outside woofers and tweeter: L/F and R/F.
Pos 3: (Centre-speaker) all drivers wired for mono.
I post a pic so you can use your imagination. Imagine it's a single cabinet.
Can this be wired?
Laying the Sony SS-Fe9s on their sides inspired me. Can I make a switch?
Pos 1: 4 x 3.5" woofers in a single cabinet would make an excellent sound-base for the TV (full-range, stereo),
Pos 2: (3.1) Centre woofers = centre channel. Outside woofers and tweeter: L/F and R/F.
Pos 3: (Centre-speaker) all drivers wired for mono.
I post a pic so you can use your imagination. Imagine it's a single cabinet.
3.5-way Falcon like Baffleless Concept Speaker (some design study)
- By Yotomeczek
- Multi-Way
- 2 Replies
Attachments
2SK177 replace with S2K170 - Technics SU-V8X - fet differential amp, pre drive, cascade servo pcb
- By MaccAu
- Solid State
- 3 Replies
A friend who knows Technics very well and has a large collection, helped me with my Technics SU-V8X. It can not set bias, at the outputs, it had high voltage across E CB and my friend said something is wrong on the amp board.
I took out all 24 transistors ( that included the 4 MosFets). The transistors seem to test fine, had some issues with C on Q315/6, however i think that was the micro clips, not making contact, so after 2 more readings C was fine under 800.
I then moved to the MosFets and followed a video online, and i never got OL( open on my meter is 1) readings, just low numbers like 148 158 on my 3.5 digit meter, so i assume they are defective?
Since 2SK117 is discontinued, by chance i went through my spares, and found my spare V4X phono pcb and found 4 2SK170 mosfets (which i hope are fine, as ive stored them in a box over the years).
Specs are very similar , voltage is lower with the 170s, and it actually appears lower noise? I tempted to try them, however will check some resistors first in the path to see if there is any defective. Only difference is VFDS -50v vs - 40v, otherwise pretty close
This might be useful thread for a reference for the parts as well, i hope.
2SK117 Product details
Low Noise Audio Amplifier Applications
• High |Yfs|: |Yfs| = 15 mS (typ.) (VDS= 10 V, VGS= 0)
• High breakdown voltage: VGDS= −50 V
• Low noise: NF = 1.0dB (typ.)
(VDS= 10 V, ID= 0.5 mA, f = 1 kHz, RG= 1 kΩ)
• High input impedance: IGSS= −1 nA (max) (VGS= −30 V)
------------------------------
2SK170 Product details
Low Noise Audio Amplifier Applications
• Recommended for first stages of EQ and M.C. head amplifiers.
• High |Yfs|: |Yfs| = 22 mS (typ.) (VDS = 10 V, VGS = 0, IDSS = 3 mA)
• High breakdown voltage: VGDS = −40 V
• Low noise: En = 0.95 nV/Hz1/2 (typ.) (VDS = 10 V, ID = 1 mA, f = 1 kHz)
• High input impedance: IGSS = −1 nA (max) (VGS = −30 V)
Fet differential amps Q301-304.
(if Mods think it suits the part section - please move it there, as i was not sure which of the two this belonged thanks Sam )
I took out all 24 transistors ( that included the 4 MosFets). The transistors seem to test fine, had some issues with C on Q315/6, however i think that was the micro clips, not making contact, so after 2 more readings C was fine under 800.
I then moved to the MosFets and followed a video online, and i never got OL( open on my meter is 1) readings, just low numbers like 148 158 on my 3.5 digit meter, so i assume they are defective?
Since 2SK117 is discontinued, by chance i went through my spares, and found my spare V4X phono pcb and found 4 2SK170 mosfets (which i hope are fine, as ive stored them in a box over the years).
Specs are very similar , voltage is lower with the 170s, and it actually appears lower noise? I tempted to try them, however will check some resistors first in the path to see if there is any defective. Only difference is VFDS -50v vs - 40v, otherwise pretty close
This might be useful thread for a reference for the parts as well, i hope.
2SK117 Product details
Low Noise Audio Amplifier Applications
• High |Yfs|: |Yfs| = 15 mS (typ.) (VDS= 10 V, VGS= 0)
• High breakdown voltage: VGDS= −50 V
• Low noise: NF = 1.0dB (typ.)
(VDS= 10 V, ID= 0.5 mA, f = 1 kHz, RG= 1 kΩ)
• High input impedance: IGSS= −1 nA (max) (VGS= −30 V)
------------------------------
2SK170 Product details
Low Noise Audio Amplifier Applications
• Recommended for first stages of EQ and M.C. head amplifiers.
• High |Yfs|: |Yfs| = 22 mS (typ.) (VDS = 10 V, VGS = 0, IDSS = 3 mA)
• High breakdown voltage: VGDS = −40 V
• Low noise: En = 0.95 nV/Hz1/2 (typ.) (VDS = 10 V, ID = 1 mA, f = 1 kHz)
• High input impedance: IGSS = −1 nA (max) (VGS = −30 V)
Fet differential amps Q301-304.
(if Mods think it suits the part section - please move it there, as i was not sure which of the two this belonged thanks Sam )
bass reflex vs double chamber reflex (ABC/DCR and DCAAV)
- By frankz55
- Subwoofers
- 5 Replies
Attachments
For sale: 4 used Peerless 830452 10" XLS Subwoofers: $50 each, includes shipping
- By bourbon-neat
- Swap Meet
- 5 Replies
I have 4 used Peerless 830452 10" XLS Subwoofers that I want to sell. The price is $50 each and includes USPS flat rate shipping to 48 US states (no HI, AK). These subwoofers have been sitting on a shelf in my garage for at least 5 years. They were used in an open baffle project that I took apart.
For Sale Firstwatt F4 complete kit with high quality parts
- Swap Meet
- 8 Replies
Hello dear diyaudio friends
I have a complete brand new kit, consisting of four F4 channels for a balanced mono construction. Everything is included, already partly assembled. The boards are from an older group buy in the German analog forum. As said the boards are partly assembled, please check pictures for details. Q1 and Q2 are precision matched 2SK370 and 2SJ108, the power transistors are precision matched IRFP240 and IRFP9240 (Keratherm Red insulators are included). Rectifying diodes are high quality HEXFRED HFA08TB60. BIAS resistors are Mills MRA non magnetic and non inductive ones, all other ones are non magnetic Dale RNC. Power Supply resistors are green Kiwame. Electrolytic capacitors on the amp boards are all Elna Silmic, power supply caps are all Panasonic 22000uF. With each power supply, you get two tiny rectifying boards for installing the diodes. I also have two custom made high quality 500VA (230Volts/50Hz) transformers that are fully MU capsuled. One transformer weights 4.85KG.
Price for the complete amp kit: 550 Euro SOLD Only the transformers are left
I’m also willing to trade for one or more of the following items:
(Of course, I will pay difference in value)
Manufacturer sealed bags of:
Please also take a look at my other offers in the Swap Meet
Shipping:
Shipping weight will be over 10KG for the amp kit and for the chassis over 20KG.
So the costs will strongly depend on your location. I will ship anywhere in the world. Shipping costs strongly depend on the shipping method you prefer.
Of course, I will only charge the real costs, I won't charge anything for packing materials and effort. I prefer to use Deutsche Post/DHL, but you can decide which shipper and which shipping method I should use. Very secure packing by me is obvious.
As payment method I prefer PayPal for friends and family, so no extra fees will be added. Other payment methods on request. Of course personal collection of modules in Cologne (Germany) and payment in cash is also possible.
Kind Regards
Phil
I have a complete brand new kit, consisting of four F4 channels for a balanced mono construction. Everything is included, already partly assembled. The boards are from an older group buy in the German analog forum. As said the boards are partly assembled, please check pictures for details. Q1 and Q2 are precision matched 2SK370 and 2SJ108, the power transistors are precision matched IRFP240 and IRFP9240 (Keratherm Red insulators are included). Rectifying diodes are high quality HEXFRED HFA08TB60. BIAS resistors are Mills MRA non magnetic and non inductive ones, all other ones are non magnetic Dale RNC. Power Supply resistors are green Kiwame. Electrolytic capacitors on the amp boards are all Elna Silmic, power supply caps are all Panasonic 22000uF. With each power supply, you get two tiny rectifying boards for installing the diodes. I also have two custom made high quality 500VA (230Volts/50Hz) transformers that are fully MU capsuled. One transformer weights 4.85KG.
I’m also willing to trade for one or more of the following items:
(Of course, I will pay difference in value)
Manufacturer sealed bags of:
- 2SJ74-BL
- 2SK170-GR
- 2SJ74-GR
- 2SK370-BL
- BurrBrown PCM1704-K DAC chips
- Analog Devices MAT02 and MAT03 dual monolithic transistors
- 2 x Starkrimson® Ultra Amp Module
- XRK Audio RTR TPA3255 Reference Class D amplifier
Please also take a look at my other offers in the Swap Meet
Shipping:
Shipping weight will be over 10KG for the amp kit and for the chassis over 20KG.
So the costs will strongly depend on your location. I will ship anywhere in the world. Shipping costs strongly depend on the shipping method you prefer.
Of course, I will only charge the real costs, I won't charge anything for packing materials and effort. I prefer to use Deutsche Post/DHL, but you can decide which shipper and which shipping method I should use. Very secure packing by me is obvious.
As payment method I prefer PayPal for friends and family, so no extra fees will be added. Other payment methods on request. Of course personal collection of modules in Cologne (Germany) and payment in cash is also possible.
Kind Regards
Phil
Egg-shaped WAW idea (my latest near-field iteration)
- By Kev06
- Full Range
- 25 Replies
This is the latest in an ongoing journey into new territory for me. Previous tests around the near-field theme have arrived at various (somewhat personal) conclusions:
The circles are based on (existing drivers) an alpair 5.3 and a scanspeak 15w/8530k01, which can work rather well together IMO. The mock up comprises Ikea blanda bowls in 28cm and 20cm diameters; the height is somewhat less than two stacked spheres would be, and I calculate will offer about 12Litres internal volume (before internal bracing). Probably I'd go with sealed enclosures, partly for simplicity under the circumstances and partly because I'm happy enough with how the drivers sound in them.
The alpair would want a bit less than 2Litres for a Qtc of 0.7, which would leave the 15W with sufficient for a qtc of perhaps 0.75 (depending on stuffing and braces and how the internal volume is apportioned and divided into two chambers). This will be an an active system so could be corrected in any case, but I'd just like to begin from 'approximately' suitable volumes for future flexibility.
So that is the new embryo of a plan. I don't get a lot of time off and have no workshop these days so it may take a while to realise. Combined with the complicated shape, I'll probably therefore make use of the bowls and go for a painted finish, which will allow much use of glue and filler underneath. I had considered making a mould and then using glass-fiber and resin for the walls, but that all adds to time and cost. If this works then I can always use a finished speaker as a mould later, should I want to make a fiber-glass version in the future.
Cheers,
Kev
- My situation is indeed well suited to speakers of modest SPL positioned quite close to the listening position (say around 50cm give or take). I like this, where room effects are reduced and the neighbours don't complain as much, and yet the apparent location of instruments and vocals (etc) seem more natural to me than with headphones.
- My first attempts with full-range drivers were very positive indeed; I'm surprised by how much I like them. However (at least with a small enclosure) it transpires that I prefer them used in a WAW configuration.
- Speakers positioned so close can feel intrusive and also be a bit annoying for practical reasons. I've found this to be greatly improved if they are a rounded shape (rather than with corners and points), and also if they're not taking up desk-space or blocking lines of sight.
- It is to be a bespoke creation for a slightly unusual setup, so I'd like something that looks a bit unusual too.
The circles are based on (existing drivers) an alpair 5.3 and a scanspeak 15w/8530k01, which can work rather well together IMO. The mock up comprises Ikea blanda bowls in 28cm and 20cm diameters; the height is somewhat less than two stacked spheres would be, and I calculate will offer about 12Litres internal volume (before internal bracing). Probably I'd go with sealed enclosures, partly for simplicity under the circumstances and partly because I'm happy enough with how the drivers sound in them.
The alpair would want a bit less than 2Litres for a Qtc of 0.7, which would leave the 15W with sufficient for a qtc of perhaps 0.75 (depending on stuffing and braces and how the internal volume is apportioned and divided into two chambers). This will be an an active system so could be corrected in any case, but I'd just like to begin from 'approximately' suitable volumes for future flexibility.
So that is the new embryo of a plan. I don't get a lot of time off and have no workshop these days so it may take a while to realise. Combined with the complicated shape, I'll probably therefore make use of the bowls and go for a painted finish, which will allow much use of glue and filler underneath. I had considered making a mould and then using glass-fiber and resin for the walls, but that all adds to time and cost. If this works then I can always use a finished speaker as a mould later, should I want to make a fiber-glass version in the future.
Cheers,
Kev
-
Locked
Is it me, or is my integrated wired wrong?
- By eriksquires
- Parts
- 30 Replies
Hi Everyone,
So for a variety of bad reasons I took my Luxman 507ux integrated amp apart. Mainly to examine up close the IEC inlet and see about replacing it. Anyway, that issue aside, it seems the amp fuses the wrong side of the AC line?
Here's the inlet as you'd see from the back of the amplifier. I'd expect the left pin to be the line, and therefore it would eventually be the fuse wire right? Please ignore the missing fuse holder except to orient yourself. The PCB the inlet is mounted on seems to be for multiple models and/or countries. The actual fuses are further down.
The issue is the wires at the bottom of the inlet, shown below:
Underneath the inlet tabs, from left to right the wire labels read BLK and WHT. This appears to be reverse of what I would expect at least in the US. Line should be black, but it's on the right.
OK, so maybe this is just bad color coding?
However if we trace the BLK wire back to the power supply control board the BLK wire IS fused, but the WHT wire is not. In the large PCB in the middle you'll find a black transformer on the right side, the wires from the inlet terminate here:
Measuring from the wiring or the pins (as seen above) it is the BLK wire which goes straight to the fuse. You can also see the copper traces underneath.
So am I completely incorrect or does this seem like a manufacturing error in the US?
So for a variety of bad reasons I took my Luxman 507ux integrated amp apart. Mainly to examine up close the IEC inlet and see about replacing it. Anyway, that issue aside, it seems the amp fuses the wrong side of the AC line?
Here's the inlet as you'd see from the back of the amplifier. I'd expect the left pin to be the line, and therefore it would eventually be the fuse wire right? Please ignore the missing fuse holder except to orient yourself. The PCB the inlet is mounted on seems to be for multiple models and/or countries. The actual fuses are further down.
The issue is the wires at the bottom of the inlet, shown below:
Underneath the inlet tabs, from left to right the wire labels read BLK and WHT. This appears to be reverse of what I would expect at least in the US. Line should be black, but it's on the right.
OK, so maybe this is just bad color coding?
However if we trace the BLK wire back to the power supply control board the BLK wire IS fused, but the WHT wire is not. In the large PCB in the middle you'll find a black transformer on the right side, the wires from the inlet terminate here:
Measuring from the wiring or the pins (as seen above) it is the BLK wire which goes straight to the fuse. You can also see the copper traces underneath.
So am I completely incorrect or does this seem like a manufacturing error in the US?
For Sale Audiotechnology subwoofers (rare items)
To make some room... I will sell some units for projects that I won't build:
Audiotechnology 15E Flexunits Sub/woofer. VERY GOOD CONDITION
T/S parameters from Dayton Audio Test System: DATS V3:
Re 6.008 [Ohms]
Fs 22.61 [Hz]
Zm 37.73 [Ohms]
BL 16.59 [N/A]
Qms 3.361
Qes 0.6365
Qts 0.5351
Vas 219.4 [liters]
L10k 0.5365 [mH]
n0 0.3799 [%]
dBSPL 87.9 [1W/1m]
Ms 205.2 [grams]
Cms 0.242 [mm/N]
Audiotechnology 15E Flexunits Sub/woofer. VERY GOOD CONDITION
T/S parameters from Dayton Audio Test System: DATS V3:
Re 6.008 [Ohms]
Fs 22.61 [Hz]
Zm 37.73 [Ohms]
BL 16.59 [N/A]
Qms 3.361
Qes 0.6365
Qts 0.5351
Vas 219.4 [liters]
L10k 0.5365 [mH]
n0 0.3799 [%]
dBSPL 87.9 [1W/1m]
Ms 205.2 [grams]
Cms 0.242 [mm/N]
Threshold SA/1 with black face meters??
Not your typical amplifier question, more a Threshold trivia question. I have 2 pairs of SA/1 monoblocks, both black face wit the silver meters. A buddy of mine has a similar pair but just picked up a pair with black faces with black meters. They are the original meters as the amplifiers were purchased from the original owner AND they have a Threshold logo at the top. I have never seen Threshold black meters. Anyone know the history behind these? Was it a case of, "A few sitting around and we thought we'd use them" or was there an actual run of these with black meters?
Just curious!
Just curious!
Is this a Pass preamp?
Hi All
I stumbled across the attached schematic - is it a Pass preamp -if so which one?
Thanks in advance
I stumbled across the attached schematic - is it a Pass preamp -if so which one?
Thanks in advance
Let's talk about the I/V circuit with common mode servo as shown by ES9039pro datasheet
- By Tfive
- Digital Line Level
- 66 Replies
I recently came about the I/V circuit proposed by ESS's ES9039pro datasheet. Firstly let's show it here:
I will try to describe how I think it works, let's see how many misconceptions I have about it...
I will try to describe how I think it works, let's see how many misconceptions I have about it...
- There is a "deglitching" cap (C18.1) directly around the DAC outputs. I remember that this might cause problems with I/V opamp stability. Why is this suddenly not the case anymore? I see it's benefits, forming a 1st order low pass with the DAC output resistance (I calculated a cutoff of around 200kHz with 2x744 ohm output resistance of a single DAC output).
- U14.1/14.2 with their feedback components from the output to the inverting inputs form a "standard" opamp I/V circuit.
- U15/C72/R102 make an integrator with cutoff of about 2.6kHz, taking it's input from the summed I/V output (by R100/101), seeing only common mode voltage of the I/V outputs at it's inverting input. U15 noninverting input is referenced to ground.
- I/V opamps U14.1/U14.2 have a positive gain of ~744 on their noninverting inputs (R14/15/17/18) where the output of the servo is amplified.
- Where does the servo cutoff of 2.6kHz come from? Are frequencies between 2.6kHz and the edge of the audio band (20k) of lesser importance?
- Why is the servo output amplified by 744 and then works as a reference for the I/V opamps?
Help with Philips CD changer from the 80's (dead SAA7210?)
- By enryfox
- Digital Source
- 9 Replies
Attachments
How to wire transformer with 3 inputs (to replace one with 4)
- By grosso
- Power Supplies
- 4 Replies
Hi guys,
Wanting to replace an existing transformer (to fix hum and for fun of learning), I ordered a new one, in 2x115v to make it an easy replacement but it arrived as a 230v.
I’ve read about serie or parralel wiring but didn't find anything about the 3 wires only case.
The original has 4 input and output wires:
The new one only has 3 inputs / 4 outputs:
I feel ok to wire the outputs, black/black instead of blue/blue and w/w instead of brown/brown.
But how should I wire the 3 inputs on the 4 pins input connector?
Thx!
Wanting to replace an existing transformer (to fix hum and for fun of learning), I ordered a new one, in 2x115v to make it an easy replacement but it arrived as a 230v.
I’ve read about serie or parralel wiring but didn't find anything about the 3 wires only case.
The original has 4 input and output wires:
The new one only has 3 inputs / 4 outputs:
I feel ok to wire the outputs, black/black instead of blue/blue and w/w instead of brown/brown.
But how should I wire the 3 inputs on the 4 pins input connector?
Thx!
