Member Since: 10 Jun 2020
Location: Moscow
Posts: 26
Premium Sound could be better!
Hi all!
This time I’ll tell you about what you can’t individually do yourself, but it’s not difficult to ask for help from experienced repairmen of modern radio equipment. The budget for the details can be chosen by yourself.
A year has passed since the installation of a new standard amplifier for 16 channels. But there was no calmness - at home everything sounded a little different than in the car ...
So all this time was spent looking for new opportunities for implementing sound quality in relation to already implemented observations, shoveling the Internet, selecting and sweeping away dead-end projects, searching for competent specialists with an in-depth study of their experience and communicating with other "restless" colleagues foram.
Let me just remind you that the target area of business for throwing out states, pulling out numbers from GU, adding additional processors and amplifiers is for me a neighboring galaxy with its rather exclusive dispersion of life, but where I was not going to fly from the words “Absolutely!”.
On the other hand, with all my faith that JLR engineers are not fools, since they blinded such an amp (on Chipdip, an amp on one TAS5424 costs 90tr, and we have four of them!). And all possible delays are set for the speakers exactly in the regular places for each JLR model as it should, which is proved by the presence of the necessary firmware for the amplifiers in case they are rearranged with other car models. So I wanted to pull out the entire potential system, looking for and redoing everything that I thought was important, but finding all the places where the manufacturer could still cut mass production.
And finally, free time came together, accumulated significant ideas with thoughts on how to implement them, and spare parts ordered in different places to implement the next quirk-tweak for a regular amplifier!
First of all, I want to express special thanks from the bottom of my heart to the members of the forum:
z-vladimir
ostashv-evgeniy
smart sensors
And of course, to all experienced professionals who shared their experience or threw up new questions, let's go, forcing our brains to work independently in this configuration, since JLR has everything built according to the sound “not like everyone else”, and ready-made solutions and sound specialists in JLR just not (or never found by me)!
First, let me tell you what was in the final ideas:
1. Bring upgrades in the power path to a new level, extinguishing all possible interference as much as possible wherever possible. Replace ALL western electrolytes with improved ones. I found the best available in stores that could fit into a limited place in the amplifier - polymer, film and tantalum capacitors (Nichicon, WIMA, Murata, Kemet) and special electrolytes with low ESR (Nichicon KG). Places I've found worthy of special attention:
- At the power input to the input choke,
- After the throttle to the stabilizer,
- After the stabilizer and before the conversion, replace everything with polymer and dilute film,
- After conversion (immediately and polymer, and film, and tantalum),
- On each amplifier chip (in addition to the previously added high-capacity electrolytes and film-supplied tantalum and low-amplitude electrolytes),
- I also went through the power path of the DACs at each voltage - before the chokes, after the step-down stabilizers - everything for the regular and audio power paths of the DACs separately (fortunately, two high-speed stabilizers are already included in the power supply circuit for numbers and sound in the DAC- o) ah).
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Empty Amp without reworking (picture as example from another model)
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All that link managed in the free closure was shoved
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WIMA and some capacitor packages in SMD packages.
2. Replace feed-through capacitors from DACs to power amplifiers from standard ceramics (0.5 uF) to tantalum ones (10 uF). Plus - at the input of the amplifier chip. I definitely wouldn’t be able to push 32 pieces of captivity purely physically. So there's a compromise here. A few ideas to send a signal from the DAC directly to the amp without capacitors, but I didn’t risk it, because my colleague would have simply nothing to adjust the minimum voltage at the TAS5424 outputs. I'm not ready to risk my speakers!
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In the process of replacing standard ceramics with tantalum: old capacitors - removed - new capacitors are installed
3. Different levels of sensitivity of non-standard speakers led me to close, parallelize or select the values of the feed-through resistances at the inputs of the power amplifier microcircuit for the midrange and subwoofer paths (with the subwoofer as a result of even sorting out the ejection - more on that later) to determine the level of their resulting return up to high sound level of midrange and treble (after replacing the speakers with midrange, there was a noticeable subsidence, very suspicious in the frequency response, it was impossible to straighten the tone controls on the head, but the Sub was already turned out at the maximum level in the head rhythm due to the use of 4 ohm speakers instead of 2 ohm).
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Some resistors have been removed
4. Measure the final frequency response for comparison with last year and, possibly, work on item 3 again.
How it was a year ago (the frequency response in red).
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Now the frequency response looks like this (new frequency response in red as well)
I used to think about the microphone, but this sweep tone on my Test CD for some reason breaks off at 15 kHz, although the entire range below now looks nice and fairly even. The test on simple discs with music does not show such a collapse in the treble!
The finalization process took almost a week for 4-5 hours a day. Washing off protective varnish, dismantling old components with dilution of standard high-temperature solder with low-temperature solder, preparing regular places for new parts, making new sites for mounting additional SMD components, washing, placing and installing new parts, fixing mounted components with special glue, checking for leaks or short circuits …
And now — the long-awaited installation of the amplifier in place!
To begin with, I listen to a CD at a low volume, setting the tone controls to zero. A slight shock and an involuntary cry of “Who is here?”!
I remove the level of Sub to -5. For the first time in my life! Otherwise, at high volume, he tries to rip off all the fasteners and jump out of the trunk, and different notes on the double bass sound at different volumes - a clear surge at the lowest frequencies - and evened out the level of the Sub in their sound. And slowly add the volume up to 20, up to 25 and up to 30!
Emotions run high!
Almost jumping out the sunroof to Rammstein on DVD! Jazz with liveliness of instruments mercilessly kills the remnants of love for the Pet Shop Boys. Pink Floyd won't let you out of the car until the disk runs out - you have to take advantage of this pause, otherwise you won't get home! The Helsinki Symphony Orchestra throws out all the variety of its instruments, hiding nothing behind the scenes!
What can you say if you try to push emotions aside?
As a result, the scene expanded to a disgrace (again emotions!) and rose above the torpedo up - to the level of eyes and ears! This is probably due to the rise of the midrange level to the required level when reflected from the windshield. Now some instruments and voices are localized completely on the sides - in door pillars and windows! The cymbals and the bell at the Pinks became copper, without steel overtones. Naturalness and detailing leads to complete relaxation, as on home equipment. But at home you can’t add “meat” like it is now possible on Saba in the car!
Even MP3 and BT played like adults!
At a speed of 90-100 km/h, a volume level of 15-20 is enough! Above 30, I don’t even want to twist it - it gets to the liver and lays the ears!
I thought it was possible to slightly remove the level of the Sub by removing the jumpers and soldering the resistance from the midrange channels to the parallel in order to bring all the tone settings to zero on the head, but then I decided to leave the Sub control at -5 for maximum volume, and the Sub is closer to zero output at low listening - as tone compensation!
To my regret, I will not be able to measure the contributions of each individual idea in the overall project, since I do not have sufficient technical base at home! Where and how did the distortions (if they did) go away? And which of the alterations gave a greater effect? What could be saved - I can not say. I just did my best for myself. And, judging by the changes I heard in the end, I think that it was 1000% worth it!
The old regular amp for 12 channels is still with me - I put it back in the car while soldering the 16-channel one. A direct comparison of the sound quality by throwing amps just made me mad!
So it's time to meet with car audio specialists - what will they "hear", measure and say? It would be nice if they knew how to measure output distortion by only feeding the signal from test CDs or DVDs and not from the sound card. Then it will be possible to compare the results with the old regular amp. And then, I hope, this can be called a tweak for the D-class amplifier from JLR, and not just my quirk!
PS There was one unpleasant minus — the clicks of the speakers when the engine is turned on and off. When listening "from the battery" (without starting the engine), there are no clicks. If you listen "from the battery" and start the engine, then a click jumps right through the music. How to overcome - I do not know. I would appreciate any good advice!
Member Since: 16 Jul 2015
Location: devon
Posts: 492
interesting,but,i think i will leave my hse premium system as it is
21st Jun 2022 9:27 pm
FL2Vano
Member Since: 10 Jun 2020
Location: Moscow
Posts: 26
As you like!
"Best is the enemy of the good"
I added one capacitor to wrong place and have spent another two weeks to find this mistake and to fix it.
MY13 SD4 HSE Lux
IAM2.1 Level 3
Meridian Premium Surround Sound with Extra Upgrade
22nd Jun 2022 6:35 am
CED
Member Since: 05 Apr 2014
Location: leverington
Posts: 233
sid wrote:
interesting,but,i think i will leave my hse premium system as it is
Have too agree with “Sid” haven’t any complaints with my Premium sound system. Many passengers over the years have remarked how excellent it is to their own car systems.
22nd Jun 2022 7:03 am
FL2Vano
Member Since: 10 Jun 2020
Location: Moscow
Posts: 26
Agree that as default it sounds well compare with others. This is a reason why I decided not to build an alternative Amp.
I compared sound in my Freelander not with other cars - I compared it with sound at my home. And I don't see big different from now. So I'm happy!MY13 SD4 HSE Lux
IAM2.1 Level 3
Meridian Premium Surround Sound with Extra Upgrade
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21st Jun 2022 2:21 pm
