I have prepared an EXCEL sheet for the current ACA-PCB order (see image attached).
I have taken my forum's nickname as a "standard" order.
The standard contains:
- 1 pair (2 pcs.) of ACA PCBs (cost: 15€)
- 12 (4 x 0R22, 4 x 0R47, 4 x 0R56) FUTABA 5W resistors (cost: 13€)
- registered shipping (cost: 7.20€)
- PAYPAL fee: 3€
This sums up to 38.20€.
If it is o.k. for you: please transfer the sum to my PAYPAL-ID: RRozek@t-online.de
Do not forget and leave your Forum's nickname, home-address and EMail-address in the PAYPAL sheet.
If you want to change anything (f.e.: no resistors): leave a message in the thread.
I will order next Friday (08.01.2021) for those, who have paid me.
Best regards - Rudi_Ratlos
I have taken my forum's nickname as a "standard" order.
The standard contains:
- 1 pair (2 pcs.) of ACA PCBs (cost: 15€)
- 12 (4 x 0R22, 4 x 0R47, 4 x 0R56) FUTABA 5W resistors (cost: 13€)
- registered shipping (cost: 7.20€)
- PAYPAL fee: 3€
This sums up to 38.20€.
If it is o.k. for you: please transfer the sum to my PAYPAL-ID: RRozek@t-online.de
Do not forget and leave your Forum's nickname, home-address and EMail-address in the PAYPAL sheet.
If you want to change anything (f.e.: no resistors): leave a message in the thread.
I will order next Friday (08.01.2021) for those, who have paid me.
Best regards - Rudi_Ratlos
Attachments
Rudi, can I offer you some advice - don't include your personal e-mail address on open forum posts - the various bots will collect it and store it to spam you etc. You've told the world your mail address and the fact that you have a Paypal account that uses it. Best to use the forum PM facility.
In the meantime, I still have to build my project using the boards I got from you in the previous group buy, can I come into this round and just buy a set of resistors?
Cheers
Ray
In the meantime, I still have to build my project using the boards I got from you in the previous group buy, can I come into this round and just buy a set of resistors?
Cheers
Ray
Hot as in;
- Temperature
- Sound quality/performance
- Both
Neat build BTW.
Just soak testing on the bench atm and it does get hot.
Tomorrow I'll hook it up to a set of speakers
Gentlemen, find attached an image with the current status of the order.
I will include a CD with a couple of tracks (.wav) of a "AreYouAuthentic" - Sound-Juror CD.
I have attached the 2nd file of it - so you know, what I am talking about.
Not only will you be able to confirm that you have done everything right with your current build, but this CD allows me to send you the letter
with your order (PCB and resistors) as "documentation letter", the shipment of which costs much less than a "parts letter".
Best regards - Rudi_Ratlos
I will include a CD with a couple of tracks (.wav) of a "AreYouAuthentic" - Sound-Juror CD.
I have attached the 2nd file of it - so you know, what I am talking about.
Not only will you be able to confirm that you have done everything right with your current build, but this CD allows me to send you the letter
with your order (PCB and resistors) as "documentation letter", the shipment of which costs much less than a "parts letter".
Best regards - Rudi_Ratlos
Attachments
Hi Rudi, did you see my previous post about the resistors?
https://www.diyaudio.com/forums/gro...based-rectifier-capmx-psu-17.html#post6472326
Ray
https://www.diyaudio.com/forums/gro...based-rectifier-capmx-psu-17.html#post6472326
Ray
Just that the original ACA boards could be configured as monos to up the power output
@geoturbo: have a look at the attached picture showing the ACA's possible operation modes.
@nautibuoy: chiily's build shows 2 speaker ports (Spkr and SpkrRtn) driven from his ACA. IMHO he built a "standard stereo ACA".
@chiily: your build looks o.k.
But you do definitely not need a LT4320 based rectifier.
Calculate yourself: the ACA consumes 8W per channel operated from a 24VDC PSU.
According to: P = U * I, this results in an "operational" current of < 350mA.
Add to this the BIAS (quiescent) current of about 1.6A, telling you that an ACA channel will consume no more than 2A of current.
An LT3420 is "only" needed, when "lot of current" (>>2A) is consumed and the "time to update" your reservoir caps
(the time when the rectified transformers AC is bigger than the reservoir caps' current DC) benefits from the LT3420-schematic !
A 20VAC/2A single secondary transformer will "theoretically" do for a ACA-channel, but due mechanical, magnetic, ... losses:
be genorous and "double" the transformers wattage.
Your 75VA transformers (what about its secondaries' AC?) is absolutely sufficient in my eyes.
Do never even think about bridging an ACA!
I have once listened to a bridged ACA and have been very much disappointed by its sound.
If you need to provide more power to your speakers: think about building another ClassA (F5, F6, M2, ...)
- or change to ClassA/B - "my SYMASYM" (2nd image) for example
- or even think about bi-amping your speakers with ACA (heights and mid) and SYMASYM (Sub)
Regards - Rudi_Ratlos
@nautibuoy: chiily's build shows 2 speaker ports (Spkr and SpkrRtn) driven from his ACA. IMHO he built a "standard stereo ACA".
@chiily: your build looks o.k.
But you do definitely not need a LT4320 based rectifier.
Calculate yourself: the ACA consumes 8W per channel operated from a 24VDC PSU.
According to: P = U * I, this results in an "operational" current of < 350mA.
Add to this the BIAS (quiescent) current of about 1.6A, telling you that an ACA channel will consume no more than 2A of current.
An LT3420 is "only" needed, when "lot of current" (>>2A) is consumed and the "time to update" your reservoir caps
(the time when the rectified transformers AC is bigger than the reservoir caps' current DC) benefits from the LT3420-schematic !
A 20VAC/2A single secondary transformer will "theoretically" do for a ACA-channel, but due mechanical, magnetic, ... losses:
be genorous and "double" the transformers wattage.
Your 75VA transformers (what about its secondaries' AC?) is absolutely sufficient in my eyes.
Do never even think about bridging an ACA!
I have once listened to a bridged ACA and have been very much disappointed by its sound.
If you need to provide more power to your speakers: think about building another ClassA (F5, F6, M2, ...)
- or change to ClassA/B - "my SYMASYM" (2nd image) for example
- or even think about bi-amping your speakers with ACA (heights and mid) and SYMASYM (Sub)
Regards - Rudi_Ratlos
