Hi,
I'd say the only thing you can do is investigate swapping
the tweeter, or tweaking the crossover to the tweeter.
I think the first version was a bit relentless in the treble,
and the later version somewhat more laid back.
A minor tweak would be stuffing the centre one of the
three ports, may or may not suit your room better,
if it does you will get slightly deeper and faster bass.
/sreten.
I'd say the only thing you can do is investigate swapping
the tweeter, or tweaking the crossover to the tweeter.
I think the first version was a bit relentless in the treble,
and the later version somewhat more laid back.
A minor tweak would be stuffing the centre one of the
three ports, may or may not suit your room better,
if it does you will get slightly deeper and faster bass.
/sreten.I owned a pair of 753 (late 90's) for about six years and was happy with high and mid ranges but never thought they went low enough. Adding a sub helped a lot but always thought they missed that “magical” something?
Also found they couldn’t cope with complex electronic music like The Flaming Lips – Yoshima Battles the Pink Robots – that just freaked them out.
I tried some minor tweaks but Mission probably got the best configuration anyway. I then splashed out and built the Seas Thor Transmission Lines and these made the 753’s sound like a bag of potatoes??????
Also found they couldn’t cope with complex electronic music like The Flaming Lips – Yoshima Battles the Pink Robots – that just freaked them out.
I tried some minor tweaks but Mission probably got the best configuration anyway. I then splashed out and built the Seas Thor Transmission Lines and these made the 753’s sound like a bag of potatoes??????
Hmm....
The 753's I've heard made a much better job of boogying along with
the music than a lot of other speakers, without being hypercritical of
the quality of the source.
Really low bass is given up for higher volume capability further up,
and with the high overall sensitivity, good volume with modest amps.
Having said that I think I've only heard the Freedom version.
It is true the basic limitations of the bass/mid driver means
that they can't be tweaked to provide audio perfection.
But I found them a very enjoyable speaker, with good bass
timing, and capable of playing a lot louder than any small
5" bass/mid+tweeter loudspeaker.
Possibly investigate floor coupling, blutacking them to
stone / concrete slabs to improve bass and stability.
/sreten.
The 753's I've heard made a much better job of boogying along with
the music than a lot of other speakers, without being hypercritical of
the quality of the source.
Really low bass is given up for higher volume capability further up,
and with the high overall sensitivity, good volume with modest amps.
Having said that I think I've only heard the Freedom version.
It is true the basic limitations of the bass/mid driver means
that they can't be tweaked to provide audio perfection.
But I found them a very enjoyable speaker, with good bass
timing, and capable of playing a lot louder than any small
5" bass/mid+tweeter loudspeaker.
Possibly investigate floor coupling, blutacking them to
stone / concrete slabs to improve bass and stability.
/sreten.Sreten - I'm not saying the 753 were a bad speaker, overall I enjoyed mine for 6 years - you wouldn't keep a pair that long if they didn't do something right. At the time of buying they were the best I auditioned in that price range and I listened to a lot of models.
No, it was just I wanted to move up in quality from the 753's and to seriously improve on them I'd have had to spend a huge amount at retail, so I built myself the Thors.
Now the clarity and presentation of Seas top of the range drivers is “stunnin” and make everything else I’ve heard sound “veiled” and “slow”. Now some people do not like the Thors for various reasons and say they are a “hard” sound – but with my environment, setup or ears I do not hear that so I’m absolutely sold on these speakers but they are merciless on badly recorded CDs. However no speaker is perfect and in my bass light room I need a sub woofer to fill in the very lows.
My 753 were pre the Freedom models and I never heard the newer versions so perhaps they were even better.
No, it was just I wanted to move up in quality from the 753's and to seriously improve on them I'd have had to spend a huge amount at retail, so I built myself the Thors.
Now the clarity and presentation of Seas top of the range drivers is “stunnin” and make everything else I’ve heard sound “veiled” and “slow”. Now some people do not like the Thors for various reasons and say they are a “hard” sound – but with my environment, setup or ears I do not hear that so I’m absolutely sold on these speakers but they are merciless on badly recorded CDs. However no speaker is perfect and in my bass light room I need a sub woofer to fill in the very lows.
My 753 were pre the Freedom models and I never heard the newer versions so perhaps they were even better.
Some almost free upgrade for your 753 is to take the drive units out and all the foam linning and varnish or paint the enclosure on the inside, you can even use a glue neat if you like, after that you can use that butimus stuff, its just black tar in a sheet forum.
You can get better quality componets on the cross over, up grade the wiring as well.
This will cost you very little and give some improvement in quality, you could also fill the base with sand or lead short if you like.
We had a pair of Freedoms in the garage for years, very nice sound considering what they cost us.
You can get better quality componets on the cross over, up grade the wiring as well.
This will cost you very little and give some improvement in quality, you could also fill the base with sand or lead short if you like.
We had a pair of Freedoms in the garage for years, very nice sound considering what they cost us.
Hi,
At the time the whole street outside the garage was being retarded with bitumen asphalt type material, we asked one of the workers if they would tar some pacthes in our yard and they said no problem, it was then I got him too pour some into the Mission enclosures, the drive units were blown at the time and i was waiting for replacement from the UK, the boxes almost doubled in weight after that and they stunk for a while but it made a difference in the focus of the lower mid bass, i know you can buy the bitumen in pellets and melt it in a old pot and do the same thing, the pads that are sold buy hi-fi shops are like a cheaper version and dont bond as well as the hot liquid version.
If you do melt the bitumen pellets in a pot do not even think about doing it in your home or your wife or partner will kill you!
At the time the whole street outside the garage was being retarded with bitumen asphalt type material, we asked one of the workers if they would tar some pacthes in our yard and they said no problem, it was then I got him too pour some into the Mission enclosures, the drive units were blown at the time and i was waiting for replacement from the UK, the boxes almost doubled in weight after that and they stunk for a while but it made a difference in the focus of the lower mid bass, i know you can buy the bitumen in pellets and melt it in a old pot and do the same thing, the pads that are sold buy hi-fi shops are like a cheaper version and dont bond as well as the hot liquid version.
If you do melt the bitumen pellets in a pot do not even think about doing it in your home or your wife or partner will kill you!
blast from the past... mission 753i's
i have dug out my old 753's from the loft and the tweeters dont work.. suprise, suprise. I know that the 753's tweeters were very prone to blow as they are the second set ive had in mine.i have bought a second hand pair with working tweeters but tatty looking. my question is as follows. Should i replace the tweeters or should i replace the crossover aswell to be on the safe side as i think the ones i bought are a later model. many thanks dan.
i have dug out my old 753's from the loft and the tweeters dont work.. suprise, suprise. I know that the 753's tweeters were very prone to blow as they are the second set ive had in mine.i have bought a second hand pair with working tweeters but tatty looking. my question is as follows. Should i replace the tweeters or should i replace the crossover aswell to be on the safe side as i think the ones i bought are a later model. many thanks dan.
Hi
Mission 753's are my favourite. you can tell if your donor speakers are the later model, by checking out the look of them.
The origionals are supplied with an alu tweeter, hidden behind a black mesh grill. The later model was a silk dome tweeter, no grill AFAIK.
The crossover went through various revisions through the life of the 753. so probably you will want to use the later crossover. Check though the lytic caps in the crossover for bulging.
Incidentally, someone here had blown tweeters on his 753's and managed to source replacement coils. I think that they came from the states somewhere, maybe madison. They were the silk dome variety. I think they are peerless replacements, but memory tells me thats who made the drivers origionally. They are probably different impedance than the metal domes though.
As for improvements to be made. I can tell you from personal experiance, in order of recomendation.
On the non-freedom (1st gen) model, the best mod is free. Remove the tweeter, unclip it from its mount and push out the metal grill that covers the tweeter. Instant improvement on the top end clarity of the speaker.
The low and mid bass clarity can be improved by strengthening the baskets. I used no more nails to do this and got a nice improvement. I think any sort of reinforcement, or dampening is wothwhile here.
Recable them with something beefy. I use mag wire. The standard cables are pretty cheap offerings.
Replace the inline cap ono the tweeter for improved top end, Sonicap was what I used, nice improvement of top end. you may need to adjust the attenuating resistor in the crossover to quieten the tweeter after this.
A nice solid base for them is nice, but does not make a dramatic difference. I used blocks of Slate.
Mission 753's are my favourite. you can tell if your donor speakers are the later model, by checking out the look of them.
The origionals are supplied with an alu tweeter, hidden behind a black mesh grill. The later model was a silk dome tweeter, no grill AFAIK.
The crossover went through various revisions through the life of the 753. so probably you will want to use the later crossover. Check though the lytic caps in the crossover for bulging.
Incidentally, someone here had blown tweeters on his 753's and managed to source replacement coils. I think that they came from the states somewhere, maybe madison. They were the silk dome variety. I think they are peerless replacements, but memory tells me thats who made the drivers origionally. They are probably different impedance than the metal domes though.
As for improvements to be made. I can tell you from personal experiance, in order of recomendation.
On the non-freedom (1st gen) model, the best mod is free. Remove the tweeter, unclip it from its mount and push out the metal grill that covers the tweeter. Instant improvement on the top end clarity of the speaker.
The low and mid bass clarity can be improved by strengthening the baskets. I used no more nails to do this and got a nice improvement. I think any sort of reinforcement, or dampening is wothwhile here.
Recable them with something beefy. I use mag wire. The standard cables are pretty cheap offerings.
Replace the inline cap ono the tweeter for improved top end, Sonicap was what I used, nice improvement of top end. you may need to adjust the attenuating resistor in the crossover to quieten the tweeter after this.
A nice solid base for them is nice, but does not make a dramatic difference. I used blocks of Slate.
753's need high current power
The best thing that you can do to modify an original pair of 753's is to remove the mesh grill over the tweeters. The difference is profound in terms of smoothing out and rounding off any harshness of the highs. Secondly, these speakers are power hungry. They need clean, high current power in order to be controlled. I power them with a Cyrus Two paired with a PSX power supply, which is pushing about 100 WPC, given the 6 OHM impedence of the speakers. Any feedback that you read on line about tweeters failing, are a direct result of the speakers being underpowered, NOT overpowered. And, as with any better quality speaker, it's a garbage in garbage out scenario. If you are using a run of the mill source (ie: anything less than a $1,000 - $1,500 CD player) you will be disappointed. Focus on a high quality source with clean high current power and you will not be disappointed with the 753's - oh, and do pop those mech grills of off the tweaters too.
The best thing that you can do to modify an original pair of 753's is to remove the mesh grill over the tweeters. The difference is profound in terms of smoothing out and rounding off any harshness of the highs. Secondly, these speakers are power hungry. They need clean, high current power in order to be controlled. I power them with a Cyrus Two paired with a PSX power supply, which is pushing about 100 WPC, given the 6 OHM impedence of the speakers. Any feedback that you read on line about tweeters failing, are a direct result of the speakers being underpowered, NOT overpowered. And, as with any better quality speaker, it's a garbage in garbage out scenario. If you are using a run of the mill source (ie: anything less than a $1,000 - $1,500 CD player) you will be disappointed. Focus on a high quality source with clean high current power and you will not be disappointed with the 753's - oh, and do pop those mech grills of off the tweaters too.
hi guys
dont know if im posting in the right place so my appolagies if not. i managed to blow one of my mission 753 tweeters after investagating the diapharam was damaged i managed to uncoil one turn the wire and re fix the speaker works but very quiet?is this because of the one less loop? im only getting 0.03 ohms across the terminals dont really know how to test as everything is soldered ,if diaphram is unrepairable where can i get one or something similar ??
hope someone can help
dont know if im posting in the right place so my appolagies if not. i managed to blow one of my mission 753 tweeters after investagating the diapharam was damaged i managed to uncoil one turn the wire and re fix the speaker works but very quiet?is this because of the one less loop? im only getting 0.03 ohms across the terminals dont really know how to test as everything is soldered ,if diaphram is unrepairable where can i get one or something similar ??
hope someone can help
Just been working on a pair of very early 753's, so thought I'd revive this thread.
The 753 has always been a favourite of mine, and I've owned two of the original and one pair of Freedoms.
Despite my affection for these things, they are a bit of an enigma, and there's much room for improvement. They were very affordable considering the quality of the cabinet was way above what you'd typically get at the price.
To meet that price point economies were made in terms of components, and compromises made for ease of assembly. And some aspects are just unfathomable.
One interesting fact is that, although they look like they would be a 2.5 way design, they are actually a 3-way, as the upper pair of mid-bass drivers are high-pass filtered.
The most obvious characteristic of the original is the excessive treble, both audible and measured, too hot by about 3 dB. Those Vifa-made tweeters are actually not bad, but are run way too hot. I have found variously no attenuation, 0.5 ohms and 1 ohm in different samples. Substituting a 3/3.3 ohm resistor gives a nice balance, and while you're there, make sure the resistor and cap have been connected in the proper order!
You'll notice that Mission, as they did with all their speakers from that era, use over-sized ring terminals to connect to the binding posts, resulting in poor contact. Replacing with correct size rings is worthwhile.
As is by-passing the series 470 uF electrolytic caps in series with the upper mid-bass units.
If you find the speakers are bass light for your system/room, try shorting out the 2.2 ohm resistor in the lower-bass crossover.
You might be tempted to re-wire your 753's. The problem is, any wiring improvements are going to be compromised by the brass pins that pass through the cabinet divider. these have a lot of mass, and it's difficult to get a good solder joint. Even the factory couldn't.
Best to run the new wire direct to the top cavity, either by punching out the pins and using those holes, or drilling new holes. A bit of a pain.
I've got other ideas for more radical mods. Later.
The 753 has always been a favourite of mine, and I've owned two of the original and one pair of Freedoms.
Despite my affection for these things, they are a bit of an enigma, and there's much room for improvement. They were very affordable considering the quality of the cabinet was way above what you'd typically get at the price.
To meet that price point economies were made in terms of components, and compromises made for ease of assembly. And some aspects are just unfathomable.
One interesting fact is that, although they look like they would be a 2.5 way design, they are actually a 3-way, as the upper pair of mid-bass drivers are high-pass filtered.
The most obvious characteristic of the original is the excessive treble, both audible and measured, too hot by about 3 dB. Those Vifa-made tweeters are actually not bad, but are run way too hot. I have found variously no attenuation, 0.5 ohms and 1 ohm in different samples. Substituting a 3/3.3 ohm resistor gives a nice balance, and while you're there, make sure the resistor and cap have been connected in the proper order!
You'll notice that Mission, as they did with all their speakers from that era, use over-sized ring terminals to connect to the binding posts, resulting in poor contact. Replacing with correct size rings is worthwhile.
As is by-passing the series 470 uF electrolytic caps in series with the upper mid-bass units.
If you find the speakers are bass light for your system/room, try shorting out the 2.2 ohm resistor in the lower-bass crossover.
You might be tempted to re-wire your 753's. The problem is, any wiring improvements are going to be compromised by the brass pins that pass through the cabinet divider. these have a lot of mass, and it's difficult to get a good solder joint. Even the factory couldn't.
Best to run the new wire direct to the top cavity, either by punching out the pins and using those holes, or drilling new holes. A bit of a pain.
I've got other ideas for more radical mods. Later.
I've just finished modding a pair of 753 Freedoms.
First thing to note is that the Freedom is in fact a 2.5 way speaker, so it's no surprise they sound considerably warmer than the original.
Not so much to do with the much simpler crossover on these. If anything they are a tad dull, so I replaced the original 3.3 ohm tweeter resistors with 2.7's.
Replaced all the ring terminals, cleaned up the binding posts, got rid of the ferrous nuts and washers, by-passed the elcap across the upper mid-bass drivers with a small value Wima, as there's no room for an equivalent value poly cap.
Interestingly, those same back to back 470 uF caps that high pass filter the upper mids in the original, are used to shunt the lower units in the Freedom.
Before the mods the sound was distinctly "meh', rather uninspiring.
Post mods, they've sprung to life, fast and engaging as a 753 should be.
First thing to note is that the Freedom is in fact a 2.5 way speaker, so it's no surprise they sound considerably warmer than the original.
Not so much to do with the much simpler crossover on these. If anything they are a tad dull, so I replaced the original 3.3 ohm tweeter resistors with 2.7's.
Replaced all the ring terminals, cleaned up the binding posts, got rid of the ferrous nuts and washers, by-passed the elcap across the upper mid-bass drivers with a small value Wima, as there's no room for an equivalent value poly cap.
Interestingly, those same back to back 470 uF caps that high pass filter the upper mids in the original, are used to shunt the lower units in the Freedom.
Before the mods the sound was distinctly "meh', rather uninspiring.
Post mods, they've sprung to life, fast and engaging as a 753 should be.
