MXR EVH 117 Flanger

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.

MXR EVH 117 Flanger

Postby Coolcat0078 » 28 Mar 2013, 12:30

I have an EVH 117 flanger in for repair. I can take some pictures if someone is interested. It uses a (weird) v3204 dunlop branded BBD device..
Coolcat0078
 
Posts: 7
Joined: 15 Sep 2009, 01:21
Has thanked: 0 time
Have thanks: 2 times

Re: MXR EVH 117 Flanger

Postby Govmnt_Lacky » 28 Mar 2013, 17:26

Pictures are ALWAYS welcome!

Can NEVER have enough pics! Please do :thumbsup
Govmnt_Lacky
Resistor Ronker
 
Posts: 380
Joined: 24 Mar 2011, 14:00
Has thanked: 11 times
Have thanks: 42 times

Re: MXR EVH 117 Flanger

Postby pedalgrinder » 28 Mar 2013, 21:02

yes pictures please make sure you take both component and track side so if one of wants to have a go at tracing it we can get a schematic together cheers :applause: :thumbsup
What's the best thing about fat chicks and scooters? There both fun to ride around until your mates find out!
User avatar
pedalgrinder
Cap Cooler
 
Posts: 552
Joined: 29 Aug 2011, 07:05
Location: South Australia Adelaide
Has thanked: 201 times
Have thanks: 150 times

Re: MXR EVH 117 Flanger

Postby Ice-9 » 28 Mar 2013, 21:06

I would imagine this pedal like a lot of the newer MXR stuff is pretty mutch all SMD, I would love to see a couple of pics of the pcb. :applause:
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?
User avatar
Ice-9
Transistor Tuner
 
Posts: 1013
Joined: 31 Mar 2009, 16:29
Has thanked: 131 times
Have thanks: 340 times

Re: MXR EVH 117 Flanger

Postby Coolcat0078 » 28 Mar 2013, 22:51

2 Quick pictures so you can see the pcb. I will make larger/better ones for tracing purpose.

Does anyone have some info on the v3204 IC? Could it be a rebranded v3205?
This specific pedal sometimes starts to make a huge amount of random weird noise like self oscillation, so knowing what BBD is in there may be interesting to know.

Image
Image
Coolcat0078
 
Posts: 7
Joined: 15 Sep 2009, 01:21
Has thanked: 0 time
Have thanks: 2 times

Re: MXR EVH 117 Flanger

Postby Scruffie » 29 Mar 2013, 04:05

Rebranded v3205? No...

It's just a specially for MXR made MN3204, it's 512 stages.
Scruffie
Opamp Operator
 
Posts: 1729
Joined: 13 Mar 2009, 18:59
Location: London.. ish, Uk
Has thanked: 27 times
Have thanks: 136 times

Re: MXR EVH 117 Flanger

Postby Coolcat0078 » 29 Mar 2013, 08:27

So I guess this hasn't got a direct replacement?
Coolcat0078
 
Posts: 7
Joined: 15 Sep 2009, 01:21
Has thanked: 0 time
Have thanks: 2 times

Re: MXR EVH 117 Flanger

Postby Scruffie » 29 Mar 2013, 18:17

Coolcat0078 wrote:So I guess this hasn't got a direct replacement?

Not unless you ask MXR for one.

The oscillation issues will be feedback or clock adjustments probably, you should probably ask MXR which trim controls which parameter and what the set up procedure is if you're going down that route.
Scruffie
Opamp Operator
 
Posts: 1729
Joined: 13 Mar 2009, 18:59
Location: London.. ish, Uk
Has thanked: 27 times
Have thanks: 136 times

Re: MXR EVH 117 Flanger

Postby POTL » 21 Nov 2017, 22:56

there are ideas that makes sa572?
You do not have the required permissions to view the files attached to this post.
POTL
Solder Soldier
 
Posts: 226
Joined: 26 Sep 2016, 04:11
Has thanked: 47 times
Have thanks: 48 times

Re: MXR EVH 117 Flanger

Postby EddieTavares » 22 Nov 2017, 02:42

Sa572 is a compander, one half compress the signal befor the digital portion and the other half expand the signal after that.
User avatar
EddieTavares
Breadboard Brother
 
Posts: 67
Joined: 12 Jan 2010, 14:43
Has thanked: 1 time
Have thanks: 8 times

Re: MXR EVH 117 Flanger

Postby POTL » 22 Nov 2017, 04:28

Yes, but why is it needed in the flanger circuit?
It is used in analogue delays, in the original scheme with sad1024 it was not used.
http://rudn.nodevice.com/preview/big/373/373202-1.jpg
POTL
Solder Soldier
 
Posts: 226
Joined: 26 Sep 2016, 04:11
Has thanked: 47 times
Have thanks: 48 times

Re: MXR EVH 117 Flanger

Postby Ice-9 » 23 Nov 2017, 00:11

POTL wrote:Yes, but why is it needed in the flanger circuit?
It is used in analogue delays, in the original scheme with sad1024 it was not used.
http://rudn.nodevice.com/preview/big/373/373202-1.jpg


My guess would be to simply lower noise in a BBD based circuit, same as it does in a delay.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?
User avatar
Ice-9
Transistor Tuner
 
Posts: 1013
Joined: 31 Mar 2009, 16:29
Has thanked: 131 times
Have thanks: 340 times

Re: MXR EVH 117 Flanger

Postby Scruffie » 23 Nov 2017, 00:18

Ice-9 wrote:
POTL wrote:Yes, but why is it needed in the flanger circuit?
It is used in analogue delays, in the original scheme with sad1024 it was not used.
http://rudn.nodevice.com/preview/big/373/373202-1.jpg


My guess would be to simply lower noise in a BBD based circuit, same as it does in a delay.

I concur, the circuit is obviously quite different to the original, this uses a 512 stage BBD but the original used the SAD1024 in series mode so 1024 stage BBD... maybe rather than get two types of BBDs they just increased the delay length from half the stages and then needed to cut the noise down that introduced. Who knows without a schematic and/or clock readings though.
Scruffie
Opamp Operator
 
Posts: 1729
Joined: 13 Mar 2009, 18:59
Location: London.. ish, Uk
Has thanked: 27 times
Have thanks: 136 times

Re: MXR EVH 117 Flanger

Postby POTL » 23 Nov 2017, 00:22

Scruffie wrote:
Ice-9 wrote:
POTL wrote:Yes, but why is it needed in the flanger circuit?
It is used in analogue delays, in the original scheme with sad1024 it was not used.
http://rudn.nodevice.com/preview/big/373/373202-1.jpg


My guess would be to simply lower noise in a BBD based circuit, same as it does in a delay.

I concur, the circuit is obviously quite different to the original, this uses a 512 stage BBD but the original used the SAD1024 in series mode so 1024 stage BBD... maybe rather than get two types of BBDs they just increased the delay length from half the stages and then needed to cut the noise down that introduced. Who knows without a schematic and/or clock readings though.


It seems even more strange why use the rare component mn3204 and expensive sa572 if you could just set nm3207 or nm3007 and get a 1024 stage BBD
POTL
Solder Soldier
 
Posts: 226
Joined: 26 Sep 2016, 04:11
Has thanked: 47 times
Have thanks: 48 times

Re: MXR EVH 117 Flanger

Postby Scruffie » 23 Nov 2017, 00:27

They use the 3204 in the micro flanger and I haven't checked but I think possibly the choruses too. It's not rare for them as it's made especially for them.

Probably use the 572 in their delays, cheaper to have a lot of one part produced than less of two separate parts.

Could be other design reasons though, as I said, can't say without a schematic and/or clock readings but I doubt they made an accounting mistake.
Scruffie
Opamp Operator
 
Posts: 1729
Joined: 13 Mar 2009, 18:59
Location: London.. ish, Uk
Has thanked: 27 times
Have thanks: 136 times


Return to Modern Stompbox Effects (1975 - ...)

Who is online

Users browsing this forum: No registered users and 9 guests