There are two Op-Amp chip styles - the often less expensive varieties (IC's) can be had for as little as $2.99 USD each. However, the other category of chips are known as being discrete versions. The discrete models are usually larger (by an order of 1.5 to 3x the size of the smaller IC versions). I now own 9 different class D models, 4 of which allow one the ability to change out the Op-Amps. Although these amps were relatively inexpensive, I still went ahead and obtained the more expensive discrete versions - in this case, I found the Sparks Labs SS3602 (dual channel op amps - that's important) to be the best. For example, using the Aiyima A300 as an example - I had to put in 5 Op-Amps in that one (yes, the Sparkos Labs ones), and it turned the sound signature of that amp into one that would make you think it cost $1000 or more In addition, this Op-Amp change out made the A300 sound more like a class AB amp. Same with the Aiyima A07 (which takes 2 Op-Amps). I put 2 Sparkos Labs discrete versions in there (again - these are dual channel chips - not 1 channel), and the resulting sound change (for the better) was significant - more open, warmer, more dynamic. So yes, I've been Op-Amp rolling now for a few years and I've long since discovered that you get what you pay for, and the discrete versions - whether from Burson or Sparkos Labs (there are other minor companies that make them also) - can make a world of difference. Here's a quick great video from Sparkos Labs on changing Op-Amps, along with the difference between IC and discrete versions. It's a bit quirky and comedic in spots, but the guy is actually an electronic genius. Everybody should see this: th-cam.com/video/cdYFH9ms9EE/w-d-xo.html The Sparkos Labs website is located here: sparkoslabs.com/
I got one of these for my son and have it playing via BT through some tiny mini monitors and a powered sub built from Parts Express components. I cannot believe how good it sounds in his attic office space. Truly remarkable. For the money, it blows many Hi Fi setups away. I may give him my Wiim Mini, but as good as it is already, it is gilding the lily.
Hey, thanks for the video, discrete op amp upgrades are an interesting one, I have yet to experiment with it. I would say the only thing really holding me back is that a chip like the SS3602 from Sparko's carries a price tag that is nearly the same as the entire amp. I would be interested if there were some noteable budget friendly suggestions that are priced more in line with the product they are going into, just to experiment with.
@ForeverAnalog - FIrst off, thank you for the videos! Honest/Unbiased comment here: In preparation to upgrade my new BT20A Pro, I removed the Sparkos SS3602 Chips from my Aiyima A07 (that I rolled 3 months ago) I am waiting for my BT20A Pro to arrive, In the meantime I put the original 5532 chips back in the Aiyima A07. Conclusion: Wow! the Sparkos SS3602 Chips sound significantly better. I heard the difference when I first swapped it out 3 months ago. But swapping the 5532 back into the Aiyima was a huge let down. Now I am probably going to purchase another set of SS3602 chips. I can't go back. LOL!
One revision to your video. One MUST buy a 48-Volt Power Supply with greater amperage output in order to get the 300WPC it advertises. That wattage output rating is not obtainable with the 32-volt power supply that comes with it.
@Ken Lyon Absolutely. You won't get the claimed 300 watts with the 48 watt power supply either, but maybe 100 into 8 ohms and 150 into 4, which is still fantastic for such a tiny amp. Reckon it will run pretty hot, though.
Apart from the possibility of changing the opamp, why would one get this one over the Bt30d Pro which has much more features and costs about the same? It's also TPA3255.
Fair question - I haven't heard the BT30D Pro so I can't speak to any direct comparisons - these little amps keep getting announced left and right and I do wonder if at some point if there will be market saturation issues.
With the Aiyima A07 , my preference was with the OPA 2134PA as the best low cost option and the Sparkos 3602 in a premium discreet unit. I have the BT20A Pro on order and will be trying them in that application once I have a good handle on it's stock presentation.
The output of these products is absolutely different. You need to check the specs. The pro is not just a more robust og, it doesn't have the same ohms or watts.
What's your speaker budget? Honestly, these amps can drive almost anything on the market so it's really more about the speaker qualities themselves. I only own Emotiva and Klipsch bookshelf speakers so can only really speak to those.
@@ForeverAnalog thank you for your reply. It would be under £200. I thought of wharfedale diamond 9.1. By the way thanks for sharing the discount coupon.
I can follow you, I am very fond of some Breezer T-amps I have bought that sounds fantastic for the price ... but an ´Analog Forever´ T-shirt 🙂🙂 Do yourself a favor at put 2 LM4562 op-amps in the amp, and you will love it to pieces. Of course Sparkos 3602 are better, but they cost the same as the amp.
The wiim mini & pro has a feature that can control the volume of any amp that has no remote. Just turn off Fixed volume output in Audio settings. It's worth buying just for that feature and the EQ.
Thanks, just wondering cuz there are like 3 videos out on this product today. Cheap audio guys review said he had to go over talking points and send his video in before for review before publishing.. I absolutely appreciate your reviews. Thanks for the Bluetooth critique.
All these reviews trashing BT is odd, i has a BT receiver that has a DAC and it sounds good to me! Maybe peeps are not using BT with a gud dac? I stream Flac and no complaints...
I bought the bt20a pro because it was not expensive and i was curious. I don't need it at all since i love my smsl da-9 amazing clean amps (i have 3 of them). I hooked up the bt20 pro and thought i would listen for an hour and then put it away BUT.... i listened to it for 5 days because it was not fatiguing at all and I wanted to listen to it for a month. I had to force myself to hook up the da-9 back because they sound great too and look MUCH better on my desk. Summery, bt20 pro sounds great and it's very relaxing to listen to and very easy to enjoy. Use the bass and treble knobs they make the amp come to life. Get the minidsp 2x4hd or even better get the minidsp flex to get any amp sounding 10x better. Also the schiit Lokius will make your speakers sound much better with any amp.
I haven't used mine in a few months (due to reviewing a lot of products this year) but I never noticed any lack in the volume control when it was in operation. Thank you for the kind words!
I am using android phone and flac files with Monitor Audio speakers with BT20A sounds really good so if the pro has better specs it must be great but I am not upgrading for now happy with my setup
apple is using sbc codec for bt , plus stream music is compressed , i used android phone to bt , i think bt20a doesnt have aptx bt ,not sure about the pro model , i play flac file plus a music app called poweramp , btw AIC is mine jam , but mad season river of deceit on mine playlist , i can hear clarity on it
i have the original bt20a running through the p20 with tubes.I like the sound.I did experiment with an aiyima a07 but didnt really see much improvement.i recently picked up some mission 761 and i use spotify or tidal through pc.
Very interesting video. I have always been anti Class D, but I bought a Fosi P1 tube preamp and even though it's a tube device, I'm sure it's Class D. It sounds great like my Sabaj A10h headphone amp that I use as a remote volume control with my vintage gear. I'm sure it's Class D and it is awesome.
The A08 Pro's auto defeating to Bluetooth feature annoys me so much that I haven't gotten it out of the box once after my review, lol. I know that sounds petty, but it drives me nuts!
Im trying to pick between the ayima a07 pro/max and the bt20a non pro and pro idk what to pick because the non pro bta20 a is om sale for €75 and the pro is €115 in my country and the ao7 max is €123 and the a07 pro is €128 im running a couple B&W 686 8ohm speakers Pls someone give me some advice 😅
@@ForeverAnalog i would just like to controll the bass and treble on the amp itself im not that smart with eq software and al that other stuff (but i already own a bt20a non pro for my Q acoustic 3030i and its preforming amazing for the last 2years) There is also a Marantz M-CR611 for €200 near me if that would be a solid options but it is a 4ohm vcr/amp And the fosi V3 is €95
Man, I'm really digging your channel content, glad I subscribed. I "might" take advantage of that 20% off but I'm not grounded on a good direction to take now. I hope you have a hot 5 mins to digest and respond, here's my situation: Old 94' Sony gear, integrated 100w amp/tuner, 5 disc cd changer (analog only), PL-7 TT (was my dad's from the mid-80's) and finally just two simple BIC Venturi bookshelf speakers. So if I keep my amp my only route I've considered is a good multi-function DAC and replace my CD player with one that has digital out (optical and/or coax). But now I'm wondering if I should re-vamp even more, as in perhaps remove my old 94 Sony amp and go with something more modern and small like this. If so I'm thinking about my need for a pre-amp with my TT in addition to needing more than one analog RCA input (one for TT and one for CD player). So help me out here, in keeping with minimalist config. and price (not about to spend north of $300 for new gear). I'd like to find sort of an all-in-one, pre-amp, amp, BT, DAC, with a min 4 speaker driver setup. Thoughts? Thank you.
Thanks for the kind words - have you looked at the Sony STRDH190? It's not small like these class D amps, but I think it will give you a lot of the options you seek for $198. I reviewed the amp on my channel awhile back if you want my thoughts - spoiler, it surprised me, in a good way! lol
If you are interested in buying the new BT20A Pro, be sure to check the description above for a 20% code (non-affiliate), good until April 30th!
There are two Op-Amp chip styles - the often less expensive varieties (IC's) can be had for as little as $2.99 USD each. However, the other category of chips are known as being discrete versions. The discrete models are usually larger (by an order of 1.5 to 3x the size of the smaller IC versions).
I now own 9 different class D models, 4 of which allow one the ability to change out the Op-Amps. Although these amps were relatively inexpensive, I still went ahead and obtained the more expensive discrete versions - in this case, I found the Sparks Labs SS3602 (dual channel op amps - that's important) to be the best. For example, using the Aiyima A300 as an example - I had to put in 5 Op-Amps in that one (yes, the Sparkos Labs ones), and it turned the sound signature of that amp into one that would make you think it cost $1000 or more In addition, this Op-Amp change out made the A300 sound more like a class AB amp. Same with the Aiyima A07 (which takes 2 Op-Amps). I put 2 Sparkos Labs discrete versions in there (again - these are dual channel chips - not 1 channel), and the resulting sound change (for the better) was significant - more open, warmer, more dynamic.
So yes, I've been Op-Amp rolling now for a few years and I've long since discovered that you get what you pay for, and the discrete versions - whether from Burson or Sparkos Labs (there are other minor companies that make them also) - can make a world of difference.
Here's a quick great video from Sparkos Labs on changing Op-Amps, along with the difference between IC and discrete versions. It's a bit quirky and comedic in spots, but the guy is actually an electronic genius. Everybody should see this:
th-cam.com/video/cdYFH9ms9EE/w-d-xo.html
The Sparkos Labs website is located here:
sparkoslabs.com/
This is excellent information, thank you! I haven't had time to figure out where to start on op amps lol. Thanks again!
Good info-Thanks
I got one of these for my son and have it playing via BT through some tiny mini monitors and a powered sub built from Parts Express components. I cannot believe how good it sounds in his attic office space. Truly remarkable. For the money, it blows many Hi Fi setups away. I may give him my Wiim Mini, but as good as it is already, it is gilding the lily.
Yeah I’m about to send this one with my sons to their college apartment lol. Thanks for watching!
Hey, thanks for the video, discrete op amp upgrades are an interesting one, I have yet to experiment with it. I would say the only thing really holding me back is that a chip like the SS3602 from Sparko's carries a price tag that is nearly the same as the entire amp. I would be interested if there were some noteable budget friendly suggestions that are priced more in line with the product they are going into, just to experiment with.
Yeah I’m curious how many folks do actually swap them out!
I wish there was a cheaper alternative as well. But, I did the upgrade to the Aiyima A07 and the audio improvement is undeniable.
Try the OPA2134PA for approx
$15/pr.
@Douglas Blake RC4558 are nothing close to HiFi, old crap.
@ForeverAnalog - FIrst off, thank you for the videos!
Honest/Unbiased comment here: In preparation to upgrade my new BT20A Pro, I removed the Sparkos SS3602 Chips from my Aiyima A07 (that I rolled 3 months ago) I am waiting for my BT20A Pro to arrive, In the meantime I put the original 5532 chips back in the Aiyima A07.
Conclusion: Wow! the Sparkos SS3602 Chips sound significantly better. I heard the difference when I first swapped it out 3 months ago. But swapping the 5532 back into the Aiyima was a huge let down. Now I am probably going to purchase another set of SS3602 chips. I can't go back. LOL!
Very interesting. Thank you for sharing!
You confuse people - they are 5532, and they a the worst crap.
The opa2134 is a good example. It's used in some Akitika preamps.
Thank you! Did you build the Akitika yourself? I would love to build one!
I have both and the Pro runs quite warm (35C) when idle, anyone else see this (48v PSU)?
One revision to your video. One MUST buy a 48-Volt Power Supply with greater amperage output in order to get the 300WPC it advertises. That wattage output rating is not obtainable with the 32-volt power supply that comes with it.
Yes excellent point thank you!
With the supplied SMPS the real world output is approx 45-50 w / ch @ 8ohms & 90-95 w /ch @4ohms
@Ken Lyon Absolutely. You won't get the claimed 300 watts with the 48 watt power supply either, but maybe 100 into 8 ohms and 150 into 4, which is still fantastic for such a tiny amp. Reckon it will run pretty hot, though.
Apart from the possibility of changing the opamp, why would one get this one over the Bt30d Pro which has much more features and costs about the same? It's also TPA3255.
Fair question - I haven't heard the BT30D Pro so I can't speak to any direct comparisons - these little amps keep getting announced left and right and I do wonder if at some point if there will be market saturation issues.
Hi , what about over heating problem .. please reply
None for me
With the Aiyima A07 , my preference was with the OPA 2134PA as the best low cost option and the Sparkos 3602 in a premium discreet unit. I have the BT20A Pro on order and will be trying them in that application once I have a good handle on it's stock presentation.
Awesome. Would love to know how they sound!
The output of these products is absolutely different. You need to check the specs. The pro is not just a more robust og, it doesn't have the same ohms or watts.
I ordered one too. If you could help me out what bookshelf speaker would go with it. Regarding Ohm and watts thanks.
What's your speaker budget? Honestly, these amps can drive almost anything on the market so it's really more about the speaker qualities themselves. I only own Emotiva and Klipsch bookshelf speakers so can only really speak to those.
@@ForeverAnalog thank you for your reply. It would be under £200. I thought of wharfedale diamond 9.1. By the way thanks for sharing the discount coupon.
I can follow you, I am very fond of some Breezer T-amps I have bought that sounds fantastic for the price ... but an ´Analog Forever´ T-shirt 🙂🙂
Do yourself a favor at put 2 LM4562 op-amps in the amp, and you will love it to pieces. Of course Sparkos 3602 are better, but they cost the same as
the amp.
Thanks for the wonderful video. The pre out in it, is it variable can be controlled through volume control of the amplifier ?
Qual a diferença no som entre o BT20A Pro e o Cambridge AXA25?
What is the difference in sound between the BT20A Pro and the Cambridge AXA25?
A remote would be nice. A balance knob and AptX would also be really useful.
The wiim mini & pro has a feature that can control the volume of any amp that has no remote. Just turn off Fixed volume output in Audio settings. It's worth buying just for that feature and the EQ.
Great point thank you!
Does not have usb input, right?
@@jrdelat5 right. Only optical & rca
Isn't the Bluetooth problem an apple issue since it doesn't support LDAC?
Just a question, you said they send the item to you, but do they require you to send them your review before publishing?
No - thanks for asking!
Thanks, just wondering cuz there are like 3 videos out on this product today. Cheap audio guys review said he had to go over talking points and send his video in before for review before publishing.. I absolutely appreciate your reviews. Thanks for the Bluetooth critique.
@@Mikegritz Thanks for the kind words!
All these reviews trashing BT is odd, i has a BT receiver that has a DAC and it sounds good to me! Maybe peeps are not using BT with a gud dac? I stream Flac and no complaints...
My review actually says not to throw your BT in the trash 😂
I bought the bt20a pro because it was not expensive and i was curious. I don't need it at all since i love my smsl da-9 amazing clean amps (i have 3 of them). I hooked up the bt20 pro and thought i would listen for an hour and then put it away BUT.... i listened to it for 5 days because it was not fatiguing at all and I wanted to listen to it for a month. I had to force myself to hook up the da-9 back because they sound great too and look MUCH better on my desk. Summery, bt20 pro sounds great and it's very relaxing to listen to and very easy to enjoy. Use the bass and treble knobs they make the amp come to life. Get the minidsp 2x4hd or even better get the minidsp flex to get any amp sounding 10x better. Also the schiit Lokius will make your speakers sound much better with any amp.
Awesome! Thank you for sharing!
Hello, I have enjoyed your channel for years. Does your 20a pro have a little slack in the volume control when turning it back and forth? Thank you.
I haven't used mine in a few months (due to reviewing a lot of products this year) but I never noticed any lack in the volume control when it was in operation. Thank you for the kind words!
I am using android phone and flac files with Monitor Audio speakers with BT20A sounds really good so if the pro has better specs it must be great but I am not upgrading for now happy with my setup
Awesome. Thank you for watching!
apple is using sbc codec for bt , plus stream music is compressed , i used android phone to bt , i think bt20a doesnt have aptx bt ,not sure about the pro model , i play flac file plus a music app called poweramp , btw AIC is mine jam , but mad season river of deceit on mine playlist , i can hear clarity on it
Not true apple uses aac codec rich sound good on iOS
i have the original bt20a running through the p20 with tubes.I like the sound.I did experiment with an aiyima a07 but didnt really see much improvement.i recently picked up some mission 761 and i use spotify or tidal through pc.
Awesome! Thank you for watching!
i really dig the mingus referance. horns talking and all!by the way im not sure what this means. can you describe whats called (sylibent) thanks!
Thank you - Sibilance is like a hissing sound whenever the letter s or other combinations are used - kind of sounds like a snake lol
I've been really happy with the sound of the fosi bt 20 AS , I hooked it to my Sonys and Polk's and it was excellent on both
Awesome! It’s a fun little amp
So does a pre-out mean that you can control the volume of a powered subwoofer using the amps volume knob or is it the same thing as a line level out?
You can use sub, yes!
I'd like to know the answer to that as well. I think the pre-out will control the sub volume but don't know for sure.
Thanks for the review! I'll be checking back to look at to look at the comments about swapping out the chips too.
Thanks! I just haven’t had time to dig into op amp swapping so hoping others will help us all out!
No Excuses and the EP Jar of flies is one of my favourites.
I think it was some of their best work as a group!
Hi, can I connect with mixer or equalizer this small amplifier?
You could connect a DJ mixer to the one RCA input, yes, but I'm not sure how to connect an EQ given there is only one input on the amp.
@@ForeverAnalog ok thanks I know the process is like power amplifier, thank you
Get a Wiim Pro and control the volume/EQ with the app and you're set!
VERY TRUE! Thanks for watching!
The Mini will do this too. The Pro just has RCAs instead of mini jacks and a more conventional chassis style if you like that.
Very interesting video. I have always been anti Class D, but I bought a Fosi P1 tube preamp and even though it's a tube device, I'm sure it's Class D. It sounds great like my Sabaj A10h headphone amp that I use as a remote volume control with my vintage gear. I'm sure it's Class D and it is awesome.
Yeah class d has come a long way!
@Douglas Blake I never thought of that.
How would you compare this vs the Aiyima A08 Pro?
The A08 Pro's auto defeating to Bluetooth feature annoys me so much that I haven't gotten it out of the box once after my review, lol. I know that sounds petty, but it drives me nuts!
I didn’t even plug the antenna nor ever hooked up the Bluetooth. Using solely to listen to vinyl thus not having that irritating problem.
Excellent idea!!!!!
Im trying to pick between the ayima a07 pro/max and the bt20a non pro and pro idk what to pick because the non pro bta20 a is om sale for €75 and the pro is €115 in my country and the ao7 max is €123 and the a07 pro is €128 im running a couple B&W 686 8ohm speakers
Pls someone give me some advice 😅
Do you need Bluetooth?
@@ForeverAnalog not a must but its a nice extra
@@ForeverAnalog i would just like to controll the bass and treble on the amp itself im not that smart with eq software and al that other stuff (but i already own a bt20a non pro for my Q acoustic 3030i and its preforming amazing for the last 2years)
There is also a Marantz M-CR611 for €200 near me if that would be a solid options but it is a 4ohm vcr/amp
And the fosi V3 is €95
@@quickflik3980 I think BT20 A pro will work fine
@@ForeverAnalog but thats like almost €50 more expensive than the non pro is that realy worth it?
Can the Bluetooth be turned off?
There is not an on/off switch, but you can just not connect it to a device and it should default to RCA.
@@ForeverAnalog What if someone random is within rage, can they be prevented from connecting to it?
Cheapaudioguy says yes, you have to press the on button for a while.
@@hagbard72 he says it will disconnect any connected devices but didn't say it would turn the Bluetooth off.
I might be mistaken but as I understand it, the volume knob, if pressed & held for 5 seconds will turn off Bluetooth
My ears are so burned out I don't even want to hear music anymore
Then why are you here, and why do you comment ????
lol
sibelant?
possibly w bad dacs
honestly im starting to think the gr is the better one, the ciem drivers made sound sharper and clearer
both worth owning i guess, tm well okay too
Received one today
Returned poor sound
Care to explain more ?
Man, I'm really digging your channel content, glad I subscribed. I "might" take advantage of that 20% off but I'm not grounded on a good direction to take now. I hope you have a hot 5 mins to digest and respond, here's my situation: Old 94' Sony gear, integrated 100w amp/tuner, 5 disc cd changer (analog only), PL-7 TT (was my dad's from the mid-80's) and finally just two simple BIC Venturi bookshelf speakers. So if I keep my amp my only route I've considered is a good multi-function DAC and replace my CD player with one that has digital out (optical and/or coax). But now I'm wondering if I should re-vamp even more, as in perhaps remove my old 94 Sony amp and go with something more modern and small like this. If so I'm thinking about my need for a pre-amp with my TT in addition to needing more than one analog RCA input (one for TT and one for CD player). So help me out here, in keeping with minimalist config. and price (not about to spend north of $300 for new gear). I'd like to find sort of an all-in-one, pre-amp, amp, BT, DAC, with a min 4 speaker driver setup. Thoughts? Thank you.
Thanks for the kind words - have you looked at the Sony STRDH190? It's not small like these class D amps, but I think it will give you a lot of the options you seek for $198. I reviewed the amp on my channel awhile back if you want my thoughts - spoiler, it surprised me, in a good way! lol
wow, im new to audiophile, planning to buy bt20a pro. adding speaker playing via phone, could i add dac?
You should check out the WiiM Mini wireless streamer! Great built in DAC.
@@ForeverAnalog thanks
Just bought mine from the treadmill at the gym.
Great review.
Arriving tomorrow.
Can't wait.
Thoughts on adding the aiyima t2
tube pre amp???
I haven’t personally heard the t2 but I’m sure it would pair well. Thanks for watching!