Bob and Tom, thanks for the heads-up on the Sonicaps. Bob, is the 1.5u/200V Gen-1 Sonicap small enough to fit on-board on the version 1.3 board, or does it have to be installed off-board?
Here is the Sonicap on the Twisted Pear V1.2 board. Needs some adjustments for off-board mounting.
Thanks, Bob - it looks like a very comfy fit on the V1.3 (and V1.4) PCBs, and a bit snug but manageable even on the V1.2.
The Re-Do Dance
Hey Folks -
Unfortunately, I still have one TP V1.2 build that won’t fully cooperate. In an attempt to start over I went through the process of creating a saved project at Mouser. It is based on Dario's latest BOM.
As a shared project anyone with Mouser web access/authorization can create an order from the project and select items/quintiles according to their needs. The process is explained online.
The Digikey parts that are not available from, or are alternates to those at Mouser require a slightly different process. The attached Excel file can be uploaded to their “Auto BOM” page and then shifted to an editable sales order. Again, one must have a DigiKey account to use the service.
1. Log in to your Digikey account.
2. Go to the BOM manager page.
3. Select “Create New BOM (Upload File)”
4. Brows for file on your computer and upload. Be sure to check “XLS” button.
5. At bottom of page select “Create Order”.
Dario has noted the DigiKey LM318 is the original as specified by Mario.
.
I don’t know how many unpopulated TP V1.2 boards are out there but hopefully these two items will be helpful – even to those like me doing the re-do dance.
Mouser - https://www.mouser.com/ProjectManag...jectGUID=fd9487e6-9fc4-4208-8137-a257b0897748
Digikey – https://ordering.digikey.com/RegisteredUser/OrderFileUpload.aspx?bom=y&ppp=25
If I have missed/messed-up anything, please let me know.
Bob M.
Correction - DK.xls Quantity 1 for D1-2-3-4 should be "4".
Hey Folks -
Unfortunately, I still have one TP V1.2 build that won’t fully cooperate. In an attempt to start over I went through the process of creating a saved project at Mouser. It is based on Dario's latest BOM.
As a shared project anyone with Mouser web access/authorization can create an order from the project and select items/quintiles according to their needs. The process is explained online.
The Digikey parts that are not available from, or are alternates to those at Mouser require a slightly different process. The attached Excel file can be uploaded to their “Auto BOM” page and then shifted to an editable sales order. Again, one must have a DigiKey account to use the service.
1. Log in to your Digikey account.
2. Go to the BOM manager page.
3. Select “Create New BOM (Upload File)”
4. Brows for file on your computer and upload. Be sure to check “XLS” button.
5. At bottom of page select “Create Order”.
Dario has noted the DigiKey LM318 is the original as specified by Mario.
.
I don’t know how many unpopulated TP V1.2 boards are out there but hopefully these two items will be helpful – even to those like me doing the re-do dance.
Mouser - https://www.mouser.com/ProjectManag...jectGUID=fd9487e6-9fc4-4208-8137-a257b0897748
Digikey – https://ordering.digikey.com/RegisteredUser/OrderFileUpload.aspx?bom=y&ppp=25
If I have missed/messed-up anything, please let me know.
Bob M.
Correction - DK.xls Quantity 1 for D1-2-3-4 should be "4".
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Another Impression,
As some of you know, I am using Uriah’s Lighter Note Attenuator with my V1.3 builds. For convenience I’m temporarily using a Dogdbreath modified PS1 as a CD source.
Mick Feuerbacher Audio Projects
Based on my experiences as a member of both Big Band and Classical groups (trombone), I tend keep the volume near the high end for my version of realistic levels. I have usually had Uriah’s unit at max (about 5 o:clock) till I put the new parts in.
I found now that between 3:30 and 4:00 on the pot matches what I was using. I suspect that may be more a result of the Black Gate – maybe Andrew or someone can educate me/us in this area.
.
In any event, it’s a welcomed improvement.
More To Come……..
Bob M.
As some of you know, I am using Uriah’s Lighter Note Attenuator with my V1.3 builds. For convenience I’m temporarily using a Dogdbreath modified PS1 as a CD source.
Mick Feuerbacher Audio Projects
Based on my experiences as a member of both Big Band and Classical groups (trombone), I tend keep the volume near the high end for my version of realistic levels. I have usually had Uriah’s unit at max (about 5 o:clock) till I put the new parts in.
I found now that between 3:30 and 4:00 on the pot matches what I was using. I suspect that may be more a result of the Black Gate – maybe Andrew or someone can educate me/us in this area.
.
In any event, it’s a welcomed improvement.
More To Come……..
Bob M.
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That is correct. It is a reused chassis. I decided since the HS requirements were met on one side to keep all the power on the other.
If it were mine i'd remake the back panel and put the AC inlet and fuse in the middle the put the RCA's, BP's and amps on each side.
But since this is a donated / give-a-way chassis I will just make the suggestions to the owner.
EDIT: It's not noticeable in the picture but there is a sheet of Plexi-glass on the bottom of the chassis.
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From: CSI Bay City
To: All DIY Forensic Coroners/Experts
Ok, now I’m getting mad.
I have had great success with many projects since jumping in to this LM3886/passive attenuator world but my ego is now being threatened by my inability to breathe life into one V1.2 Ref-C build for more than a few minutes. I am considering accepting ignominious defeat and moving on, but herein make one last attempt at facing the challenge.
This is what I have done:
1. De-soldered all components and mounted them on a fresh PCB.
2. Replaced all the resistors with new (mostly Dale) parts.
3. Installed a socket for LM318 and tried alternate opamps. This resulted in about three minutes of operation before a “disconcerting buzz” and eventual failure.
4. Replaced:RELAY1,R3,C1,C2,C10,C12,C14,C15,C16,C30,C32,C34,ZD1,ZD2,Q1,Q2,Q3, DR1-4 and D2-4 with fresh parts.
5. Swapped from non-functioning to good board for operational confirmation: C3,C4,C5,C8,C6,C11,C14, - all worked perfectly on good build.
6. Removed LM318 socket and directly soldered opamp to PCB
.
At this point all voltage readings are either out of range or fluctuate wildly.
I still have one fresh Twisted Pear board, but am wondering if I can isolate the power supply components up to and separate from the signal processing components, and reconstruct that portion on a generic breadboard for testing. The interdependencies of the complete amp may prevent this type of separation. My knowledge is limited here but I’m quite willing to experiment and learn.
So I’m calling for the DIY Navy Seals and Green Barrettes for intervention before bringing this episode of “CSI Bay City” to a close.
Bob M.
To: All DIY Forensic Coroners/Experts
Ok, now I’m getting mad.
I have had great success with many projects since jumping in to this LM3886/passive attenuator world but my ego is now being threatened by my inability to breathe life into one V1.2 Ref-C build for more than a few minutes. I am considering accepting ignominious defeat and moving on, but herein make one last attempt at facing the challenge.
This is what I have done:
1. De-soldered all components and mounted them on a fresh PCB.
2. Replaced all the resistors with new (mostly Dale) parts.
3. Installed a socket for LM318 and tried alternate opamps. This resulted in about three minutes of operation before a “disconcerting buzz” and eventual failure.
4. Replaced:RELAY1,R3,C1,C2,C10,C12,C14,C15,C16,C30,C32,C34,ZD1,ZD2,Q1,Q2,Q3, DR1-4 and D2-4 with fresh parts.
5. Swapped from non-functioning to good board for operational confirmation: C3,C4,C5,C8,C6,C11,C14, - all worked perfectly on good build.
6. Removed LM318 socket and directly soldered opamp to PCB
.
At this point all voltage readings are either out of range or fluctuate wildly.
I still have one fresh Twisted Pear board, but am wondering if I can isolate the power supply components up to and separate from the signal processing components, and reconstruct that portion on a generic breadboard for testing. The interdependencies of the complete amp may prevent this type of separation. My knowledge is limited here but I’m quite willing to experiment and learn.
So I’m calling for the DIY Navy Seals and Green Barrettes for intervention before bringing this episode of “CSI Bay City” to a close.
Bob M.
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From the information given, I'd closely re-examine the protection relay circuit, since the buzz could be the relay chattering a bit before activating. If that tests fine, good continuity, no shorts, etc., then I'd probably suspect the LM3886, since just about everything else seems to be fine.
cliclick. Music to my ears
After months of being in labor another Rev. C is born.
Fired up the first time perfectly.
Sound changed dramatically in the first 4 hours and continues to change for the last 24.
Only problem I have with this amp is that it's not mine... 🙄
EDIT: of special note is:
1. Thanks Uriah for the replacement resistors.
2. Thanks LinuxGuru for offering to send replacements but suggestion Uriah.
3. The Antek xformer is a 400VA model with static shield. Notice the purple lead on the power side. I have not heard a more quiet xformer. REALLY nice unit.
After months of being in labor another Rev. C is born.
Fired up the first time perfectly.
Sound changed dramatically in the first 4 hours and continues to change for the last 24.
Only problem I have with this amp is that it's not mine... 🙄
EDIT: of special note is:
1. Thanks Uriah for the replacement resistors.
2. Thanks LinuxGuru for offering to send replacements but suggestion Uriah.
3. The Antek xformer is a 400VA model with static shield. Notice the purple lead on the power side. I have not heard a more quiet xformer. REALLY nice unit.
Attachments
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Troy, thanks and nicely done - layout, mounting, braiding, shielding, insulating sleeves, etc. Somebody is going to enjoy a neat treat of craftmanship, apart from the great sound...
All wire is Silver Plated Teflon insulated. EDIT: the input signal wire is shielded twisted pair SPT with the shield grounded on the RCA side.
I personally would put 2 sets of RCA's on the side with the amps, put an input selector, a 2 way xo high passing the Rev. C's and feed the existing RCA's the lowpass outs for a powered sub or two.
A good volume control.
And I would change the binding posts.
That would make an IDEAL compact reference system.
I personally would put 2 sets of RCA's on the side with the amps, put an input selector, a 2 way xo high passing the Rev. C's and feed the existing RCA's the lowpass outs for a powered sub or two.
A good volume control.
And I would change the binding posts.
That would make an IDEAL compact reference system.
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Troy
If you are anywhere near Dallas you should consider coming to Lone Star Audio Fest. Its extremely fun and very social. Its just like traveling to dozens of DIYers homes and listening to their systems except they are only a room apart in the hotel. Hmm, I'm not good at describing it but man its just something not to be missed and it would be cool to met you.
Uriah
If you are anywhere near Dallas you should consider coming to Lone Star Audio Fest. Its extremely fun and very social. Its just like traveling to dozens of DIYers homes and listening to their systems except they are only a room apart in the hotel. Hmm, I'm not good at describing it but man its just something not to be missed and it would be cool to met you.
Uriah
Uriah,
You going to be there this year?
If so, see Ya there.
John
I'm looking forward to getting a dose of "DIY git'er done", to juice me up and get me back out in the shop.....