If you do use this, you might like to try
- 1R resistor in series with the bass unit. At least 5W rating
- Tuning the 70ltr box to 45Hz instead of the E70 50Hz
Aware that this project can only be classed as "experimental", I am happy to swap a resistor in or out and assess the result. I am experienced in electronic assembly but a hopeless numpty when it comes to theory and design. Thank you so much for your suggestions. I can't wait to get started on the xovers when the parts arrive. I have already mounted the drivers on a temporary baffle so initial "ear tests" can be commenced. Once I have some sort of noise coming from all four drivers I can then start on the enclosures.
Yes. Double checked before I ordered the parts. The 3.25mh seen in other diagrams is incorrect, or set for a different driver.
It may be helpful to followers of this thread to illustrate the drivers you have said you intend to use for the 4" midrange and 10" bass duties.
Peerless M10NG 4" Bass / Midrange - Willys-Hifi Ltd
Celestion TF1020 - Pressed Chassis Mid Bass Driver
Perhaps kgrlee could comment on whether their sensitivity ratings will allow them to work well together.
Have you decided on which horn tweeter to buy yet?
Peerless M10NG 4" Bass / Midrange - Willys-Hifi Ltd
Celestion TF1020 - Pressed Chassis Mid Bass Driver
Perhaps kgrlee could comment on whether their sensitivity ratings will allow them to work well together.
Have you decided on which horn tweeter to buy yet?
We still do not know why you have two sets of figures for the M10NG - crucially you give two sensitivity figures - are these for different versions of the drivers? If so, which version do you have?But your biggest problem is finding a good midrange. I'm not sure why you've got 2 sets of figures for this Peerless unit but it needs to be a lot louder too. The M10NG is a BASS unit
Ideally I would like to get a pair of the GRS BT3-8 that kgrlee suggests but until I can find a source other than Parts Express I may well risk buying a pair of secondhand originals or Foster 49-1166-01 or Fane J22 which look identical but so far have remained strangely absent from my local ebay. Until I get lucky I will press on with my Monacor DT 107s.
The original source of the data seems no longer available, possibly because Peerless are no longer showing the M10NG on their website. It is certainly out of stock at a couple of retailers so probably of little interest to DIYers at the moment.
I have a feeling the two sets of specs are because it was offered in both 4 and 8 ohm versions. The second figure (where there are two) is for the 4ohm version which I have.
The 4 ohm 'mids' are therefore 88dB/W/m, while the 8 ohm woofers are 97dB/W/m. This is a large mismatch and the mid drivers require to be much more sensitive. While you can attenuate the mids, you cannot attenuate the woofers!
Similarly, your Monacor DT 107 dome tweeters (8 ohm, 89dB/W/m) are not sensitive enough to match with the bass speakers.
MONACOR: DT-107
You obviously do not wish to abandon your drivers so we are left with the incongruity of trying to match a crossover designed for a Wharfedale E70 with mid and HF drivers which are not designed for an E70.
Simply put, in order to emulate an E70, you require more sensitive mid and treble drivers.
Will the dB level of my mids be increased because they are doubled up in each enclosure? It may help the levels a bit.
I see your point about the tweets. The ones proposed by kgrlee are rated at 100dB which is a big difference. I might be asking for a pair for Christmas.
Hate to be a pain, but one more question. Will a mis match in spl cause the xovers to not divide the frequencies correctly?
I see your point about the tweets. The ones proposed by kgrlee are rated at 100dB which is a big difference. I might be asking for a pair for Christmas.
Hate to be a pain, but one more question. Will a mis match in spl cause the xovers to not divide the frequencies correctly?
Last edited:
(a) According to Vance Dickson’s The Loud Speaker Design Cookbook 3rd Edition:
SPL = +6 dB if the drivers are wired in parallel = unchanged if the drivers are wired in series *
(b) The dividing frequencies depend on both the crossover component values and the impedance of the drivers at the crossover frequency.
Since the crossover was designed with E70 drivers in mind, it is highly unlikely to give the same crossover frequencies with your non E70 drivers.
Sensitivity is not an influencing factor.as far as crossover frequency is concerned.
* Note that there is a lot of debate on this forum in regard to the resulting SPL e.g.:
https://www.diyaudio.com/forums/multi-way/67348-db-gain-series-vs-parallel-wiring.html
SPL = +6 dB if the drivers are wired in parallel = unchanged if the drivers are wired in series *
(b) The dividing frequencies depend on both the crossover component values and the impedance of the drivers at the crossover frequency.
Since the crossover was designed with E70 drivers in mind, it is highly unlikely to give the same crossover frequencies with your non E70 drivers.
Sensitivity is not an influencing factor.as far as crossover frequency is concerned.
* Note that there is a lot of debate on this forum in regard to the resulting SPL e.g.:
https://www.diyaudio.com/forums/multi-way/67348-db-gain-series-vs-parallel-wiring.html
There is NO debate among those who have actually tried it out. Dickason is correct.
Old Bones, I'm not sure what you are trying to do. I'm assuming you want to replicate the sound of the E70.
My recommendations for the Celestion unit are towards that end though putting resistors in series with bass units is REALLY ICKY. There are better boxes & tunings for that unit but that moves firmly into 'designing a new speaker' which you really can't do by looking at specs. eg the Celestion is inherently even louder than the E70 bass unit but then you'd need even louder mids & treble.
Your mids need to be 94dB/2.83V/1m. You might be best looking among Car Speakers for such a beast. A 4" unit with this spec is most unlikely. You might be better off with a single 5" or 6" unit with this sensitivity.
Why don't you find some 94dB/2.83V/1m units and post links for us to have a look. I'm even reluctant to suggest this cos it might give you the impression you can design speakers by looking at specs.
Don't stress about getting exact inductors. The crossover will NOT be right for anything except genuine E70 units in an E70 box. Besides, the 3.25mH was only for the twiddle knobs.
At least you've found the correct Treble unit
Last edited:
The above fact obviously can't be emphasised enough and was first stated by kgrlee as far back as post #55.
Old bones, the hard fact of the matter is that your incompatible combination of drivers and an unrelated crossover circuit can't possibly work together satisfactorily, never mind emulate a Wharfedale E70.
We have been trying to guide you gently towards a better choice of drivers. If you insist on continuing in your present direction I'm afraid you will be just as disappointed with the results as you described in your first post.
Sorry to be so blunt, but my words are intended to save you a lot of wasted time and effort.
Best wishes.
Thankyou for your comments and help. I do appreciate your candid opinions and certainly understand what you are trying to say.
"Old Bones, I'm not sure what you are trying to do. I'm assuming you want to replicate the sound of the E70."
That is correct. The only "off the peg" speakers I can afford at the moment just sound flat and nasty for the sort of music I want to listen to. My old E70s gave clean detail on the quiet bits and gut wrenching power on bass notes and percussion. Given the cult status (expensive) they now enjoy means my only option is to try my best to cobble up a clone system of some sort. I know it will never achieve the impossible and I know I will have to do a lot of experimentation to get even close but I am prepared to try. I am trying to learn and punch well above my weight but if I can come close to the result I want it will have been worth it.
OK, I'm mad but so are a lot of people.
"Old Bones, I'm not sure what you are trying to do. I'm assuming you want to replicate the sound of the E70."
That is correct. The only "off the peg" speakers I can afford at the moment just sound flat and nasty for the sort of music I want to listen to. My old E70s gave clean detail on the quiet bits and gut wrenching power on bass notes and percussion. Given the cult status (expensive) they now enjoy means my only option is to try my best to cobble up a clone system of some sort. I know it will never achieve the impossible and I know I will have to do a lot of experimentation to get even close but I am prepared to try. I am trying to learn and punch well above my weight but if I can come close to the result I want it will have been worth it.
OK, I'm mad but so are a lot of people.
kgrlee "Your mids need to be 94dB/2.83V/1m. You might be best looking among Car Speakers for such a beast. A 4" unit with this spec is most unlikely. You might be better off with a single 5" or 6" unit with this sensitivity."
Maybe so but then the E70 enclosure volume (at least the mid tubes) would be wrong. At the moment the only thing I can duplicate closely is the enclosure volume and configuration. Everything else is guesswork. Even the specs for the original drivers is unavailable so I'm flying blind here.
Maybe so but then the E70 enclosure volume (at least the mid tubes) would be wrong. At the moment the only thing I can duplicate closely is the enclosure volume and configuration. Everything else is guesswork. Even the specs for the original drivers is unavailable so I'm flying blind here.
If anyone else is interested in repairing or cloning a pair of E70s, then replacement drivers are available from the specialists in the link below.
Replacement Drivers - wharfedale-e-series-speakers-specialists
The total cost of the drivers is £572. Supply the enclosures and the crossovers and you have a bit of a bargain when you consider the cost of high end speakers!
Replacement Drivers - wharfedale-e-series-speakers-specialists
The total cost of the drivers is £572. Supply the enclosures and the crossovers and you have a bit of a bargain when you consider the cost of high end speakers!
It's not surprising you ended up with a mismatched set of drivers!
What are we to do with you?
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.