These tda7297 look better, plenty room to print Folsom on them.
https://detail.tmall.com/item.htm?spm=a230r.1.14.22.arQW0a&id=36690202464&ns=1&abbucket=9
https://detail.tmall.com/item.htm?spm=a230r.1.14.22.arQW0a&id=36690202464&ns=1&abbucket=9
My boards (all gone) were printed by Rush PCB from my Gerber. The capacitor multiplier used is a variation on Keantokens, with his permission. I bare no relation to rebranders.
TI makes NE5532 etc etc etc
You use Panasonic Oscons and most likely rebranded other parts too, Harman et all rebrand chips to sell spares or hide what they use, so lighten up, you are not only one LOL
You use Panasonic Oscons and most likely rebranded other parts too, Harman et all rebrand chips to sell spares or hide what they use, so lighten up, you are not only one LOL
I may be buying things to use that are rebranded, as there's no distinction from mouser or other legit suppliers, but I don't rebrand anything my myself. I'm not worried, just want to be clear. It hardly matters since I've got no boards atm anyway.
Is there a way to achieve this on the stock e-bay board? Maybe by cutting some traces and hardwiring others?
Thanks! I wasn't aware that the thread was updated for the SG changes.
Another question: The datasheet shows a 0.10uF paralled with a 470uF for the power decoupling caps. The 470uF was implemented by you and was said to benefit. The 0.10uF ceramic was said to cause ringing and was asked to be removed. Would it maybe benefit if the 0.10uF + 470uF were soldered at the appropriate legs of the 7297?
After reading all of this I bought 2 of these to see what the fuss was all about, 1 to keep as standard for reference and the other to modify.
I've thrown number 1 into a alloy box with connectors and fed it with a 12V dc brick smps for starters and fired it up.
And it works!
Low dc offsets, no noise or hum.
Volume control fairly well balanced and listening to it now playing a CD of Julia Fordham's Concrete Love.
And it's great!
Not because of the little it cost either. (£6.00 the pair delivered!)
Whether after long term listening I'll still think the same, who knows but at the moment I'm a happy chappie and in no rush to modify the other board at all.
If anybody is interested I'll report more later.
I've thrown number 1 into a alloy box with connectors and fed it with a 12V dc brick smps for starters and fired it up.
And it works!
Low dc offsets, no noise or hum.
Volume control fairly well balanced and listening to it now playing a CD of Julia Fordham's Concrete Love.
And it's great!
Not because of the little it cost either. (£6.00 the pair delivered!)
Whether after long term listening I'll still think the same, who knows but at the moment I'm a happy chappie and in no rush to modify the other board at all.
If anybody is interested I'll report more later.
A fellow told me that my version bested his F5 and Aleph J. So cost to performance, all versions, is something good.
Damn.
The other board was damaged when it arrived, the heatsink & chip were bent over at an angle and when powered up it is noisy as hell with lots of buzzing and random pops although there's is music playing.
Guess you can't expect too much for £6.00.
Dropped the seller an email but not holding out any great hopes.
That's my reference gone to judge mods by so back to the original board for now I suppose!
I've had she who must be obeyed give the working board a listen with the youngest son and they both agreed that the level of sound quality was astounding.
The other board was damaged when it arrived, the heatsink & chip were bent over at an angle and when powered up it is noisy as hell with lots of buzzing and random pops although there's is music playing.
Guess you can't expect too much for £6.00.
Dropped the seller an email but not holding out any great hopes.
That's my reference gone to judge mods by so back to the original board for now I suppose!
I've had she who must be obeyed give the working board a listen with the youngest son and they both agreed that the level of sound quality was astounding.
I've had good luck purchasing 7297s from "Homeart" on eBay. The quality is good, shipping prompt and they replaced a damaged unit quickly without any drama.
It's the same as my failed IndieGoGo kit that was overly modestly priced. The chassis has Panoma copper binding posts (and copper nuts for tattoo guns), neutrik RCA, ordinary 12x3 construction quality powercord. It's unique in many ways, but it doesn't have V-caps or anything absurd.
The stock amp can't achieve the quality for many reasons. A big one my guide addressed in the most recent form was the incorrect ground paths overlapping. Getting the grounding right is huge. The amp does respond well to good input capacitors. And the power coming in, like other chipamps, is a focus point due to its lack of inherent noise rejection as a chip.
I couldn't tell you if the chips from China can sound as good, since I never could get one to not blow up at 18v like mine is regulated at. In fact I let one play at 23v for a week and it was nice! However that may eventually ruin a chip.
I run at 19v on stock board no problems. Hot as heck though. Sounds better than 12v for sure. I will look at grounding issue.
Is there a way to mod the Chinese board to have the proper ground path?
Is there a way to mod the Chinese board to have the proper ground path?
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Connect both signal grounds directly to the signal ground pin so currents don't mix paths unnecessarily.