Extron gain clone [Archive] - The Art of Sound Forum

Bourney

22-12-2020, 20:42

So, I bought one of these after a recommendation by a fellow AOSer and Duncan - Tubehunter's comments on this forum. Have to say I'm massively impressed...I know a few others have bought them and I'd love to hear your thoughts as I'm struggling to understand how something so good can cost so little! :)

brian2957

22-12-2020, 20:44

Got a link please Steve :)

Bourney

22-12-2020, 20:51

https://www.extron.com/product/mls406sa

https://theartofsound.net/forum/showthread.php?71484-FS-LM3886-Gainclone-Amplifier&highlight=Tubehunter

Bourney

22-12-2020, 20:52

Can be found used on ebay for around £50.

brian2957

22-12-2020, 21:20

Thanks Steve . I'll keep my eyes peeled :)

Weeman1973

26-12-2020, 12:20

After reviewing this thread with great excitement, I remembered I got gifted an Extron MLS 304SA a little while back and never did anything with it.

I’m going to give it a run out a little later but was wondering what I need to do it (if anything) to get it singing or does anyone know if what I’ve got is more or less what you guys are talking about? (images below).

https://uploads.tapatalk-cdn.com/20201226/bf8d5d47d161f5c81913d97b5f1c81e2.jpg
https://uploads.tapatalk-cdn.com/20201226/bcdf8da9bf6fcb8232eb3d128e851cc9.jpg
https://uploads.tapatalk-cdn.com/20201226/5d3922fb4ea7031ca28b28a0b2e5a84b.jpg
https://uploads.tapatalk-cdn.com/20201226/6ceea749680be82319b2be974ede3970.jpg
https://uploads.tapatalk-cdn.com/20201226/9a644b06fbbaaccc0a10e65f00daebd0.jpg
https://uploads.tapatalk-cdn.com/20201226/c11b90f2a07c14bae08fcc50ee583f6a.jpg

Bourney

26-12-2020, 13:37

Looks like a 4 input version, can't say if its the same guts though Russ. Instructions on the base to reset any previous settings.
I really love it, a real eye opener. I'd love a high end manufacturer to hear it blind and give their opinion.

Bourney

26-12-2020, 20:38

You tried it Russ? Jake seems to think it's the same chip sets.

Weeman1973

26-12-2020, 23:02

You tried it Russ? Jake seems to think it's the same chip sets.

I didn’t yet Steve but will give it a go tomorrow.

Think I’ll try it with the KEF Q550’s I’ve got as they’re about the easiest to drive.

Quite excited to see how it lives up to say the PM4....

Weeman1973

27-12-2020, 22:52

I briefly powered it up earlier and got to say it sounds really good with the KEFs.

Going to have more time tomorrow to play around properly and hopefully can get my RPi sorted as well which will allow me a little more freedom to experiment but initial feedback is very positive considering it cost so little (well mine was free!)

donmarrese

02-01-2021, 01:53

Did a bit of scouting around and there seems to be a 50w = MLS 506SA...wonder if it has the same internals as the MLS 406sa but with more ooomph?

Lawrence001

02-01-2021, 10:55

Did a bit of scouting around and there seems to be a 50w = MLS 506SA...wonder if it has the same internals as the MLS 406sa but with more ooomph?Some of these chip amps don't use the full potential of the chip as they reduce costs on an underpowered PSU, so it's quite possible.

Sent from my BKL-L09 using Tapatalk

Folsom

07-01-2021, 20:22

I got some on the way to try. Funny I ordered one I thought to start with. It arrives, it's just a switch... Why use the same model numbers but some have amps, others don't? Ugh.

Metlor

07-01-2021, 21:12

The SA suffix to the model mumber (304 SA, 406SA)
indicates stereo amp ? These will have a set of screw speaker terminals.
Versions with a pot, but without the SA label can be used as a preamp.

They start to look a bit better if you get a stack going !🤔

hornucopia

08-01-2021, 11:02

I've got one too. It's currently playing through my 15 ohm Leak Sandwich speakers with no problem -plenty of useable headroom.
They do sound good, despite their utilitarian look.
If anyone wants it, get in touch-£ 55 inc post. I have too much equipment!

Jac Hawk

08-01-2021, 12:35

Extron is widely used in the world of Pro A/V, at my last company i used loads of Extron kit, it's built to last and is the most sought after and respected brand, anywhere you need to do A/V switching, control or signal extension you'll find an Extron product, you guys make me laugh when you say it's really cheap, in the world of Pro A/V Extron is about the most expensive you can get, but all their products are well made out of high quality parts.

Lawrence001

08-01-2021, 21:21

Says something about the price of Hifi these days...

Sent from my BKL-L09 using Tapatalk

Folsom

08-01-2021, 23:48

Says something about the price of Hifi these days...

Sent from my BKL-L09 using Tapatalk

How so, have you seen any of their retail prices?

Lawrence001

08-01-2021, 23:53

How so, have you seen any of their retail prices?No just comparing the ones people have been buying for £30 with what you pay for home audio equivalents.

Sent from my BKL-L09 using Tapatalk

Shovel_Knight

08-01-2021, 23:56

Those units on eBay are off-lease, you can't compare their selling price to new hi-fi.

Bourney

09-01-2021, 08:58

How much would they be new?

Shovel_Knight

09-01-2021, 10:36

Hundreds of euro/pounds.

Bourney

09-01-2021, 11:03

Hmmm interesting.

Jac Hawk

09-01-2021, 11:15

The one in this thread is EOL so they don't actually make them anymore, but Extron do make a range of amps, pre amps and switchers for the pro install market, Pavel is right in that these products are in the low hundreds of £ bracket. Reading this thread i'm kicking myself as the amount of old Extron gear that i've scrapped when doing system upgrades and refreshes, Extron has that bomb proof reputation it just runs and runs especially the simpler stuff that you guys are looking at and as i've said i used to just scrap anything we would take out we had so much old gear in the warehouse that we'd kept in the past we had nowhere to put it.

Folsom

13-01-2021, 21:49

Started listening.

I had to do a mod to the back to make it competitive with anything else I listen to (very easy, just snip out middle metal pieces between all the RCA inputs, this reduces injected RF). Bass is a little bit much at times but it does sound nice with modern music that way. Midrange is very easy to understand. It's a good little amp, for the money and less than an hour with a couple hand tools it's better than most people's expensive amplifiers.

Resolution isn't the best.

Metlor

16-01-2021, 12:14

Hi Jeremy, any chance you could post a photo of the metal cutting ? Don't want to ruin mine by guessing what to cut ��
Thanks mart.

Folsom

16-01-2021, 15:13

Hi Jeremy, any chance you could post a photo of the metal cutting ? Don't want to ruin mine by guessing what to cut ��
Thanks mart.

Sure thing.

https://i.ibb.co/8jcxM5b/extron.jpg (https://ibb.co/fCvNMp9)

I'm going to try this amp on a fullrange speaker set I have because they're a bit thin and lower bass to begin with, and this amp is the opposite of that to the point of being possibly too much. It might make a really nice pairing.

Metlor

16-01-2021, 15:46

Thanks Jeremy, I wouldn't know why that would make a difference, does it isolate the -ve side of the rca's.

Same here with the amps, I plan to run the bass drivers of an open baffle set, I expect they will work very well.
��

Folsom

16-01-2021, 20:42

It prevents an electrical turn. You may need to do a fair bit of reading to understand that. And yes it's basically because the ground side of the RCA's come together within the amp, but have an electrical split when entering the amplifier. You won't be disappointed if you mod it like this. It takes a few minutes with a screw driver with a few smaller tips, and a mini crescent/plier or nut driver for the VGA stand offs. Then a pair of side cutters can remove those pieces with no effort at all. You could almost do it with scissors.

Folsom

18-01-2021, 03:22

Well it's not bass-ey enough to replace a BSC filter like I think 100%.

Also the RCA inputs may not have been used, it takes a few hours to burn in, sound improves. This became an amp for some single driver speakers for my TV for now. The TV has an EQ for some BSC. We'll see if I keep it all like that.

Folsom

29-01-2021, 18:23

The sound vastly improved over a few days. I put a Hum X on mine due to the TV spewing stuff through ground, not it's wonderful. I might get another one for music/and or secondary system.